Final Text
4VAC50-20-20. General provisions.
A. This chapter provides for the proper and safe design, construction, operation and maintenance of impounding structures to protect public safety. This chapter shall not be construed or interpreted to relieve the owner or operator of any impoundment or impounding structure of any legal duties, obligations or liabilities incident to ownership, design, construction, operation or maintenance.
B. Approval by the board of proposals for an impounding structure shall in no manner be construed or interpreted as approval to capture or store waters. For information concerning approval to capture or store waters, see Chapter 8 (§62.1-107) of Title 62.1 of the Code of Virginia, and other provisions of law as may be applicable.
C. In promulgating this chapter, the board recognizes that no impounding structure can ever be completely "fail-safe," because of incomplete understanding of or uncertainties associated with natural (earthquakes and floods) and manmade (sabotage) destructive forces; with material behavior and response to those forces; and with quality control during construction.
D. Any All engineering analysis analyses
required by this chapter such as, including but not limited to,
plans, specifications, hydrology, hydraulics and inspections shall be conducted
or overseen by and bear the seal of a professional engineer licensed to
practice in Virginia.
E. Design, inspection and maintenance of impounding structures shall be conducted utilizing competent, experienced, engineering judgment that takes into consideration factors including but not limited to local topography and meteorological conditions.
E. F. The official forms as
[ called for ] by [ noted ] in
this chapter are available from the director department at the
department's website.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §1.2, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-30. Definitions.
The following words and terms when used in this chapter shall have the following meanings unless the context clearly indicates otherwise:
"Acre-foot" means a unit of volume equal to 43,560
cubic feet or 325,853 gallons (one (equivalent to one foot of
depth over one acre of area).
"Agricultural purpose" means the production of an agricultural commodity as defined in §3.1-249.27 of the Code of Virginia that requires the use of impounded waters.
"Agricultural purpose dams" means [ dams
impounding structures ] which are less than 25 feet in height or
which create a maximum impoundment smaller than 100 acre-feet, and certified
by the owner on official forms as constructed, maintained or operated
primarily for agricultural purposes.
"Alteration" means changes to an impounding structure that could alter or affect its structural integrity. Alterations include, but are not limited to, changing the height or otherwise enlarging the dam, increasing normal pool or principal spillway elevation or physical dimensions, changing the elevation or physical dimensions of the emergency spillway, conducting necessary structural repairs or structural maintenance, or removing the impounding structure. [ Structural maintenance does not include routine maintenance. ]
"Alteration permit" means a permit required for changes
any alteration to an impounding structure that could alter or affect
its structural integrity. Alterations requiring a permit include, but are not
limited to: changing the height, increasing the normal pool or principal
spillway elevation, changing the elevation or physical dimensions of the
emergency spillway or removing the impounding structure.
"Board" means the Virginia Soil and Water Conservation Board.
"Conditional operation and maintenance certificate
Operation and Maintenance Certificate" means a certificate required
for impounding structures with deficiencies.
"Construction" means the construction of a new impounding structure.
"Construction permit" means a permit required for the construction of a new impounding structure.
"Dam break inundation zone" means the area downstream of a dam that would be inundated or otherwise directly affected by the failure of a dam.
"Department" means the Virginia Department of Conservation and Recreation.
"Design flood" means the calculated volume of runoff and the resulting peak discharge utilized in the evaluation, design, construction, operation and maintenance of the impounding structure.
"Design freeboard" means the vertical distance between
the maximum elevation of the design flood and the top of the impounding
structure.
"Director" means the Director of the Department of Conservation and Recreation or his designee.
"Drill" means a type of emergency action plan exercise that tests, develops, or maintains skills in an emergency response procedure. During a drill, participants perform an in-house exercise to verify telephone numbers and other means of communication along with the owner's response. A drill is considered a necessary part of ongoing training.
"Emergency Action Plan or EAP" means a formal document that recognizes potential impounding structure emergency conditions and specifies preplanned actions to be followed to minimize loss of life and property damage. The EAP specifies actions the owner must take to minimize or alleviate emergency conditions at the impounding structure. It contains procedures and information to assist the owner in issuing early warning and notification messages to responsible emergency management authorities. It shall also contain dam break inundation zone maps as required to show emergency management authorities the critical areas for action in case of emergency.
"Emergency Action Plan Exercise" means an activity designed to promote emergency preparedness; test or evaluate EAPs, procedures, or facilities; train personnel in emergency management duties; and demonstrate operational capability. In response to a simulated event, exercises should consist of the performance of duties, tasks, or operations very similar to the way they would be performed in a real emergency. An exercise may include but not be limited to drills and tabletop exercises.
"Emergency Preparedness Plan" means a formal
document prepared for Low Hazard [ dams impounding
structures ] that provides maps and procedures for notifying owners
of downstream property that may be impacted by an emergency situation at an
impounding structure.
"Freeboard" means the vertical distance between the maximum water surface elevation associated with the spillway design flood and the top of the impounding structure.
"Height" means the structural hydraulic
height of an impounding structure. If the impounding structure spans a stream
or watercourse, height means the vertical distance from the natural bed of the
stream or watercourse measured at the downstream toe of the impounding
structure to the top of the impounding structure. If the impounding structure
does not span a stream or watercourse, height means the vertical distance from
the lowest elevation of the outside downstream limit of the
barrier to the top of the impounding structure.
"Impounding structure" [ or "dam" ]
means a man-made device structure, whether a dam across a
watercourse or other structure outside a watercourse, used or to be used
to retain or store waters or other materials. The term includes: (i) all dams
that are 25 feet or greater in height and that create an impoundment capacity
of 15 acre-feet or greater, and (ii) all dams that are six feet or greater in
height and that create an impoundment capacity of 50 acre-feet or greater. The
term "impounding structure" shall not include: (a) dams licensed by
the State Corporation Commission that are subject to a safety inspection
program; (b) dams owned or licensed by the United States government; (c) dams constructed,
maintained or operated primarily for agricultural purposes which are less
than 25 feet in height or which create a maximum impoundment capacity smaller
than 100 acre-feet; (d) water or silt retaining dams approved pursuant to
§45.1-222 or §45.1-225.1 of the Code of Virginia; or (e) obstructions in a
canal used to raise or lower water.
"Impoundment" means a body of water or other materials the storage of which is caused by any impounding structure.
"Inundation zone" means an area that could be
inundated as a result of impounding structure failure and that would not
otherwise be inundated to that elevation.
"Life of the impounding structure" and "life of the project" mean that period of time for which the impounding structure is designed and planned to perform effectively, including the time required to remove the structure when it is no longer capable of functioning as planned and designed.
"Maximum impounding capacity" means the volume of water or other materials in acre-feet that is capable of being impounded at the top of the impounding structure.
[ "Normal impounding capacity" means the
volume of water or other materials in acre-feet that is capable of being
impounded at the elevation of the crest of the lowest ungated outlet from the
impoundment.
"Normal or typical water surface elevation" means the water surface elevation at the crest of the lowest ungated outlet from the impoundment or the elevation of the normal pool of the impoundment if different than the water surface elevation at the crest of the lowest ungated outlet. For calculating sunny day failures for flood control impounding structures, stormwater detention impounding structures, and related facilities designed to hold back volumes of water for slow release, the normal or typical water surface elevation shall be measured at the crest of the auxiliary or emergency spillway. ]
"Operation and maintenance certificate Maintenance
Certificate" means a certificate required for the operation and
maintenance of all impounding structures.
"Owner" means the owner of the land on which an
impounding structure is situated, the holder of an easement permitting the
construction of an impounding structure and any person or entity agreeing to
maintain an impounding structure. The term "owner" includes may
include the Commonwealth or any of its political subdivisions, including
but not limited to sanitation district commissions and authorities. Also
included are , any public or private institutions, corporations,
associations, firms or companies organized or existing under the laws of this
Commonwealth or any other state or country, as well as any person or group of
persons acting individually or as a group.
[ "Planned land use" means land use that has been approved by a locality or included in a master land use plan by a locality, such as in a locality's comprehensive land use plan. ]
"Spillway" means a structure to provide for the controlled release of flows from the impounding structure into a downstream area.
"Stage I Condition" means a flood watch or heavy continuous rain or excessive flow of water from ice or snow melt.
"Stage II Condition" means a flood watch or
emergency spillway activation or [ dam impounding
structure ] overtopping where a [ breach
failure ] may be possible.
"Stage III Condition" means an emergency spillway
activation or [ dam impounding structure ] overtopping
where imminent failure is probable.
"Sunny day dam failure" means the [ breaching
failure ] of an impounding structure with the initial water level
at the normal reservoir level, usually at the lowest ungated principal spillway
elevation or the typical operating water level.
"Tabletop Exercise" means a type of emergency action plan exercise that involves a meeting of the impounding structure owner and the state and local emergency management officials in a conference room environment. The format is usually informal with minimum stress involved. The exercise begins with the description of a simulated event and proceeds with discussions by the participants to evaluate the EAP and response procedures and to resolve concerns regarding coordination and responsibilities.
"Top of the impounding structure" means the lowest point of the nonoverflow section of the impounding structure.
"Watercourse" means a natural channel having a
well-defined bed and banks and in which water normally flows when it
normally does flow.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §1.3, eff. February 1, 1989; amended, Virginia Register Volume 18, Issue 14, eff. July 1, 2002; Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-40. Classes Hazard potential classifications
of impounding structures.
A. Impounding structures shall be classified in one of four
categories according to size and hazard potential, three hazard
classifications as defined in subsection B of this section and Table 1. Size
classification shall be determined either by maximum impounding capacity or
height, whichever gives the larger size classification.
B. For the purpose of this chapter, hazards pertain to potential
loss of human life or property damage to the property of others
downstream from the impounding structure in event of failure or faulty
operation of the impounding structure or appurtenant facilities. Hazard
potential classifications of [ dams impounding
structures ] are as follows:
1. Impounding structures in the Class I hazard potential
category are located where High Hazard Potential is defined where an
impounding structure failure will cause probable loss of life or serious economic
damage to occupied. [ "Probable loss of life"
means that impacts will occur that are likely to cause a loss of human life,
including but not limited to impacts to residences, businesses, other occupied
structures, or major roadways. ] Economic damage may occur to, but
not be limited to, building(s), industrial or commercial facilities, important
[ primary ] public utilities, main highway(s) or
railroad(s) major [ public ] roadways,
railroads, personal property, and agricultural interests. [ "Major
roadways" include, but are not limited to, interstates, primary highways,
high-volume urban streets, or other high-volume roadways. ]
2. Impounding structures in the Class II hazard potential
category are located where Significant Hazard Potential is defined where
an impounding structure failure could may cause possible
the loss of life or appreciable economic damage. [ "May
cause loss of life" means that impacts will occur that could cause a loss
of human life, including but not limited to impacts to facilities that are
frequently utilized by humans other than residences, businesses, or other
occupied structures, or to secondary roadways. ] Economic damage
may occur to, but not be limited to occupied, building(s),
industrial or commercial facilities, [ secondary ] public
utilities, secondary highway(s) or railroad(s) or cause interruption of
use or service of relatively important public utilities [ public ]
roadways, railroads, personal property, and agricultural interests.
[ "Secondary roadways" include, but are not limited to, secondary
highways, low-volume urban streets, service roads, or other low-volume
roadways. ]
3. Impounding structures in Class III hazard potential
category are located where Low Hazard Potential is defined where an
impounding structure failure may cause minimal property damage to
others. No loss of life is expected would result in no expected loss of
life and would cause no more than minimal economic damage. [ Economic
damage may occur to, but not be limited to, building(s), industrial or
commercial facilities, secondary public utilities, secondary public roadways,
railroads, personal property and agricultural interests. "No
expected loss of life" means no loss of human life is anticipated. ]
4. Impounding structures in Class IV hazard potential
category are located where the failure of the impounding structure would cause
no property damage to others. No loss of life is expected.
5. Such size and C. The hazard potential classifications
classification [ and size category for the given hazard
classification ] shall be proposed by the owner and shall be
subject to approval by the director board. To support the
appropriate hazard classification, dam break analysis shall be conducted by the
owner's engineer. Present and projected development of planned
land-use [ for which a development plan has been officially
approved by the locality ] in the dam break inundation
zones downstream from the impounding structure shall be considered in
determining the classification.
6. D. Impounding structures shall be subject to
reclassification by the board as necessary.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §1.4, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-50. Performance standards required for impounding structures.
A. In accordance with the definitions provided by §10.1-604
of the Code of Virginia and 4VAC50-20-30, an impounding structure shall be
regulated if the [ dam impounding structure ]
is 25 feet or greater in height and creates a maximum impounding capacity of
15 acre-feet or greater, or the [ dam impounding
structure ] is six feet or greater in height and creates a maximum
impounding capacity of 50 acre-feet or greater and is not otherwise exempt from
regulation by the Code of Virginia. Impounding structures exempted from this
chapter are those that are:
1. Licensed by the State Corporation Commission that are subject to a safety inspection program;
2. Owned or licensed by the United States government;
3. Operated primarily for agricultural purposes that are less than 25 feet in height or that create a maximum impoundment capacity smaller than 100 acre-feet;
4. Water or silt-retaining dams approved pursuant to §45.1-222 or 45.1-225.1 of the Code of Virginia; or
5. Obstructions in a canal used to raise or lower water.
Impounding structures of regulated size and not exempted
shall be constructed, operated and maintained such that they perform in
accordance with their design and purpose throughout the life of the project.
For new impounding structures, the spillway(s) capacity shall perform at
a minimum to safely pass the appropriate spillway design flood as determined in
Table 1. For the purposes of utilizing Table 1, [ Maximum
Impounding Capacity and Height shall be determined in accordance with the
definitions provided in 4VAC50-20-30 and ] Hazard Potential
Classification shall be determined in accordance with 4VAC50-20-40.
TABLE 1-Impounding Structure Regulations
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[ TABLE 1
Impounding Structure Regulations
Applicable to all impounding structures that 25 feet or greater in height and that create a maximum impounding capacity of 15 acre-feet or greater, and to all impounding structures that are six feet or greater in height and that create a maximum impounding capacity of 50 acre-feet or greater and is not otherwise exempt form regulation by the Code of Virginia. ]
Hazard Potential Class of Dam |
[ |
Spillway Design Flood (SDF) [ |
Minimum Threshold for Incremental Damage [ |
|
|
[ |
[ |
|
|
High |
[ |
[ |
PMF [ |
.50 PMF |
Significant |
[ |
[ |
[ |
[ |
[ |
[ |
[ |
[ |
|
[ |
[ |
[ |
[ |
|
Low |
[ |
[ |
[ |
[ |
[ |
[ |
[ |
[ |
|
[ |
[ |
[ |
[ |
aThe factor determining the largest size
classification shall govern. [ B. The appropriate size category
is determined by the largest size associated with the maximum impounding
capacity and height of the impounding structure. ]
b [ C. B. ]
The spillway design flood (SDF) represents the largest flood that need be
considered in the evaluation of the performance for a given project. The
impounding structure shall perform so as to safely pass the appropriate SDF. Where
a range of SDF is indicated, the magnitude that most closely relates to the
involved risk should be selected. The establishment in this chapter of rigid
design flood criteria or standards is not intended. Safety must be evaluated in
the light of peculiarities and local conditions for each impounding structure
and in recognition of the many factors involved, some of which may not be
precisely known. Such can only be done by competent, experienced engineering
judgment, which the values in Table 1 are intended to supplement, not supplant.
Reductions in the established SDF may be evaluated through the use of
incremental damage [ assessment analysis ] pursuant
to 4VAC50-20-52. The SDF established for an impounding structure shall not be
less than those standards established elsewhere by state law or regulations, including
but not limited to the Virginia Stormwater Management Program (VSMP) Permit
Regulations (4VAC50-60). [ Due to potential for future development
in the dam break inundation zone that would necessitate higher spillway design
flood standards or other considerations, owners may find it advisable to
consider a higher spillway design flood standard than is required. ]
c [ D.
C. ] PMF: Probable maximum flood This means Maximum Flood is
the flood that might be expected from the most severe combination of critical
meteorologic and hydrologic conditions that are reasonably possible in the
region. The PMF is derived from the current probable maximum precipitation
(PMP) available from the National Weather Service, NOAA. In some cases local
topography or meteorological conditions will cause changes from the generalized
PMP values; therefore, it is advisable to contact local, state or federal
agencies to obtain the prevailing practice in specific cases. [ In
some cases, a modified PMF may be calculated utilizing local topography,
meteorological conditions, hydrological conditions, or PMP values supplied by
NOAA. ] Any deviation in the application of established
developmental procedures must be explained and justified by the owner's
engineer. The owner's engineer must develop PMF hydrographs for 6-, 12-, and
24-hour durations. The hydrograph that creates the largest peak outflow is to
be used to determine capacity for nonfailure and failure analysis. Present and
planned land-use conditions shall be considered in determining the runoff
characteristics of the drainage area.
[ E. D. ] 100-Yr: 100-year
flood represents the flood magnitude expected to be equaled or exceeded on the
average of once in 100 years. It may also be expressed as an exceedence
probability with a 1.0% chance of being equaled or exceeded in any given year.
Present and planned land-use conditions shall be considered in determining the
runoff characteristics of the drainage area.
d [ F. E. ].50-Yr:
50-year flood. This means represents the flood magnitude expected
to be equaled or exceeded on the average of once in 50 years. It may also be
expressed as an exceedence probability with a 2.0% chance of being equaled or
exceeded in any given year. Present and planned land-use conditions shall be
considered in determining the runoff characteristics of the drainage area.
e 100-Yr: 100-year flood. This means the flood
magnitude expected to be equaled or exceeded on the average of once in 100
years. It may also be expressed as an exceedence probability with a 1.0% chance
of being equaled or exceeded in any given year.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §1.5, eff. February 1, 1989; amended, Virginia Register Volume 18, Issue 14, eff. July 1, 2002; Volume 24, Issue 25, eff. September 26, 2008.
[ 4VAC50-20-51. Special criteria for certain low hazard impounding structures.
A. Notwithstanding the requirements of this chapter, should the failure of a low hazard potential impounding structure cause no expected loss of human life and no economic damage to any property except property owned by the impounding structure owner, then the owner may follow the below requirements instead of the requirements specified in this chapter:
1. No map required pursuant to 4VAC50-20-54 shall be required to be developed for the impounding structure should a licensed professional engineer certify that the impounding structure is a low hazard potential impounding structure and eligible to utilize the provisions of this section;
2. The spillway design flood for the impounding structure is recommended as a minimum 50-year flood; however, no specific spillway design flood shall be mandatory for an impounding structure found to qualify under the requirements of this section;
3. No emergency preparedness plan prepared pursuant to 4VAC50-20-177 shall be required. However, the impounding structure owner shall notify the local emergency services coordinator in the event of a failure or emergency condition at the impounding structure;
4. An owner shall perform inspections of the impounding structure annually in accordance with the requirements of 4VAC50-20-105. No inspection of the impounding structure by a licensed professional engineer shall be required, however, so long as the owner certifies at the time of operation and maintenance certificate renewal that conditions at the impounding structure and downstream are unchanged since the last inspection conducted by a licensed professional engineer; and
5. No certificate or permit fee established in this chapter shall be applicable to the impounding structure.
B. Any owner of an impounding structure electing to utilize the requirements of subsection A of this section shall otherwise comply with all other requirements of this chapter applicable to low hazard impounding structures.
C. The owner shall notify the department immediately of any change in circumstances that would cause the impounding structure to no longer qualify to utilize the provisions of this section. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-52. Incremental damage [ assessment
analysis ] .
A. When appropriate, the spillway design flood requirement may be reduced by the board in accordance with this section.
[ B. Prior to qualifying for a spillway design
flood reduction, certain maintenance conditions must be adequately addressed
including, but not limited to, the following:
1. Operation and maintenance is determined by the
director to be satisfactory and up to date;
2. The impounding structure is not in need of other
alteration related to the integrity of the structure;
3. Emergency Action Plan requirements set out in
4VAC50-20-175 or Emergency Preparedness requirements set out in 4VAC50-20-177
have been satisfied;
4. Inspection report requirements have been met and are
considered satisfactory by the director;
5. The applicant demonstrates in accordance with the
current design procedures and references of 4VAC50-20-320 to the satisfaction
of the board that the impounding structure as designed, constructed, operated
and maintained does not pose an unreasonable hazard to life and property;
6. The owner satisfies all special requirements imposed
by the board; and
7. Certification by the owner that these conditions will
continue to be met.
[ C. After meeting the criteria set out in
subsection B of this section, the B. The ] owner's
engineer may proceed with an incremental damage analysis. Once the owner's
engineer has determined the required spillway design flood through application
of Table 1, further analysis may be performed to evaluate the limiting flood
condition for incremental damages [ Site-specific conditions should
be recognized and considered. ] This [ assessment
analysis ] may be used to lower the spillway design flood. In no
situation shall the allowable [ reduction reduced
level ] be less than the level at which the incremental increase in
water surface elevation downstream due to failure of [ a dam
an impounding structure ] is no longer considered to present an
[ unacceptable ] additional downstream threat. This
engineering analysis will need to present water surface elevations at each
structure that may be impacted downstream of the dam. [ Water
depths greater than two feet and overbank flow velocities greater than three
feet per second shall be used to define conditions for unacceptable additional
downstream threat to persons or property. An additional downstream
threat to persons or property is presumed to exist when water depths exceed two
feet or when the product of water depth (in feet) and flow velocity (in feet
per second) is greater than seven. ]
[ D. C. ] The spillway
design flood shall not be reduced below the minimum threshold values as
determined by Table 1.
[ D. The required spillway design flood shall be subject to reclassification by the board as necessary to reflect changed conditions at the impounding structure and in the dam break inundation zone. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-54. Dam break inundation zone mapping.
A. Dam break inundation zone maps shall be provided to the
department to meet the requirements set out in Hazard Potential Classifications
of Impounding Structures (4VAC50-20-40), Emergency Action Plan for High and
Significant Potential Hazard [ Dams Impounding
Structures ] (4VAC50-20-175), and Emergency Preparedness for Low
Hazard Potential [ Dams Impounding Structures ]
(4VAC50-20-177), as applicable.
B. The location of the end of the inundation mapping should
be indicated where the water surface elevation of the dam break inundation zone
and the water surface elevation of the spillway design flood during [ a
nondam failure an impounding structure nonfailure ] event
converge to within one foot of each other. [ This would
demonstrate a level where failure of the dam does not further constitute a
hazard to downstream life or property. ] The inundation maps
shall be supplemented with water surface profiles [ and
cross-sections at critical areas ] showing the peak water
surface elevation prior to failure and the peak water surface elevation after
failure.
C. All inundation zone map(s), except those utilized in
meeting the requirements of Emergency Preparedness for Low Hazard Potential [ Dams
Impounding Structures ] (4VAC50-20-177), shall be signed and sealed
by a licensed professional engineer.
D. For determining the hazard potential classification, a minimum of the following shall be provided to the department:
1. A sunny day dam break analysis utilizing the volume retained at the normal or typical water surface elevation of the impounding structure;
2. A dam break analysis utilizing [ a
probable maximum flood the spillway design flood ] with
a dam failure; [ and ]
3. [ A dam break An ] analysis
utilizing [ a probable maximum flood the spillway
design flood ] without a dam failure [ .;
and ]
[ 4. For the purposes of future growth planning, a dam break analysis utilizing the probable maximum flood with a dam failure. ]
E. To meet the requirements of Emergency Preparedness set out in 4VAC50-20-177, all Low Hazard Potential impounding structures shall provide a simple map, acceptable to the department, demonstrating the general inundation that would result from a dam failure. Such maps do not require preparation by a professional licensed engineer, however, it is preferred that the maps be prepared by a licensed professional engineer.
F. To meet the Emergency Action Plan requirements set out in 4VAC50-20-175, all owners of High and Significant Hazard Potential impounding structures shall provide dam break inundation map(s) representing the impacts that would occur with both a sunny day dam failure and a spillway design flood dam failure.
1. The map(s) shall be developed at a scale sufficient to graphically display downstream inhabited areas and structures, roads, [ public utilities that may be affected, ] and other pertinent structures within the identified inundation area. In coordination with the local organization for emergency management, a list of downstream inundation zone property owners and occupants, including telephone numbers may be plotted on the map or may be provided with the map for reference during an emergency.
2. [ A note shall be included on each map to
state: "Mapping of flooded areas and flood wave travel times are
approximate. Timing and extent of actual inundation may differ from information
presented on this map." Each map shall include the following
statement: "The information contained in this map is prepared for use in
notification of downstream property owners by emergency management
personnel." ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-58. Local government notifications.
For each certificate issued, the impounding structure owner
shall send a copy of the certificate to the appropriate local government(s)
with planning and zoning responsibilities. A project description and the map(s)
required under 4VAC50-20-54 showing the area that could be affected by the
impounding structure [ breach failure ] shall
be submitted with the certificate. The department will provide a standard form
cover letter for forwarding the certificate copy and accompanying materials.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
[ 4VAC50-20-59. Reporting.
For the purposes of categorizing and reporting information to national and other dam safety databases, impounding structure size shall be classified as noted in Table 2.
Table 2 |
|
Maximum Impounding Capacity (Ac-Ft) |
Height (Ft) |
Large ≥ 50,000 |
≥ 100 |
Medium ≥ 1,000 & < 50,000 |
≥ 40 & < 100 |
Small ≥ 15 & < 1,000 |
≥ 6 & < 40 ] |
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part II
Permit Requirements
4VAC50-20-60. Required permits.
A. No person or entity shall construct or begin to construct
[ an a new ] impounding structure until the board has
issued a construction permit.
B. No person or entity shall alter or begin to alter an
existing impounding structure in a manner which would potentially affect its
structural integrity until the board has issued an alteration permit, or
in the case of an emergency, authorization obtained from the director. The
permit requirement may be waived if the director determines that the alteration
of improvement will not substantially alter or affect the structural integrity
of the impounding structure. Alteration does not mean normal operation and
maintenance. If an owner or the owner's engineer has determined that
circumstances are impacting the integrity of the impounding structure that
could result in the imminent failure of the impounding structure, temporary
repairs may be initiated prior to approval from the board. The owner shall
notify the department within 24 hours of identifying the circumstances
impacting the integrity of the impounding structure. Such emergency
notification shall not relieve the owner of the need to obtain an alteration
permit as soon as may be practicable, nor shall the owner take action beyond
that necessary to address the emergency situation.
C. When the board receives owner submits an
application to the board for any permit to construct or alter an
impounding structure, the director owner shall also inform
the local government of any jurisdiction which or
jurisdictions that might be affected by the permit application.
D. In evaluating construction and alteration permit
applications the director shall use the most current design criteria and
standards referenced in 4VAC50-20-320 of this chapter.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §2.1, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-70. Construction permits.
A. Prior to preparing the complete design report for a construction
permit Construction Permit, applicants are encouraged to seek
approval of the project concept from the director may submit a preliminary
design report to the department to determine if the project concept is
acceptable to the department. For this purpose the applicant should
submit The preliminary design report should contain, at a minimum, a
general description of subdivisions 1 through 4 12 of subsection
B of this section and subdivisions 1 and 2 of this subsection:
1. Proposed design criteria and a description of the size of
the impounding structure, ground cover conditions, extent of current
upstream development of within the watershed and the hydraulic,
hydrological and structural features, geologic conditions and the
geotechnical engineering assumptions used to determine the foundations foundation,
impoundment rim stability and materials to be used.
2. Preliminary drawings of a general nature, including cross sections, plans and profiles of the impounding structure, proposed pool levels and types of spillway(s).
B. An applicant for a construction permit Construction
Permit shall submit a design report on official forms. A form for
the design report [ will be is ] available
from the department (Design Report for the Construction or Alteration of
Virginia Regulated Impounding Structures). The design report shall be
prepared in accordance with 4VAC50-20-240 and shall include the following
information:. The design report is a required element of a complete
application for a Construction Permit and shall include the following
information:
1. A description of the impounding structure and
appurtenances and a proposed classification conforming with this chapter. The
description shall include a statement of the purposes for which the impoundment
and impounding structure are to be used.
1. Project information including a description of the proposed construction, name of the impounding structure, inventory number if available, name of the reservoir, and the purpose of the reservoir.
2. The proposed hazard potential classification in conformance with Table 1 of 4VAC50-20-50.
3. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude.
4. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication.
5. Owner's engineer's name, firm, professional engineer Virginia number, mailing address, and business telephone number.
6. Impounding structure data including type of material (earth, concrete, masonry or other) and the following design configurations:
a. Top of [ dam impounding
structure ] (elevation);
b. Downstream toe lowest (elevation);
c. Height of [ dam impounding
structure ] (feet);
d. Crest length exclusive of spillway (feet);
e. Crest width (feet);
f. Upstream slope (horizontal [ and
to ] vertical); and
g. Downstream slope (horizontal [ and
to ] vertical).
7. Reservoir data including the following:
a. Maximum capacity (acre-feet);
b. Maximum pool (elevation);
c. Maximum pool surface area (acres);
d. Normal capacity (acre-feet);
e. Normal pool (elevation);
f. Normal pool surface area (acres); and
g. Freeboard [ normal pool to top of dam ]
(feet).
8. Spillway data including the type, construction material, design configuration, and invert elevation for the low level drain, the principal spillway, and the emergency spillway.
9. Watershed data including drainage area (square miles); type and extent of watershed development; time of concentration (hours); routing procedure; spillway design flood used and state source; design inflow hydrograph volume (acre-feet), peak inflow (cfs), and rainfall duration (hours); and freeboard during passage of the spillway design flood (feet).
2.10. A description of properties located in the dam
break inundation zone downstream from the site of the proposed impounding
structure, including the location and number of residential structures,
buildings, roads, utilities and other property that would be endangered should
the impounding structure fail.
3. A statement from the governing body of the local
political subdivision or other evidence confirming that body is aware of the
proposal to build an impounding structure and of the land use classifications
applicable to the inundation zone. 11. Evidence that the local
government or governments have been notified of the proposal by the owner to
build an impounding structure.
4.12. Maps showing the location of the proposed
impounding structure that include: the county or city in which the proposed
impounding structure would be located, the location of roads, and
access to the site, and the outline of the impoundment. Existing aerial
photographs or existing topographic maps may be used for this purpose.
5.13. A report of the geotechnical investigations
of the foundation soils, or bedrock, or both and of the
materials to be used to construct the impounding structure.
6.14. Design assumptions and analyses sufficient
to indicate that the impounding structure will be stable during its
construction and during the life of the impounding structure under all
conditions of reservoir impoundment operations, including rapid
filling, flood surcharge, seismic loadings, and rapid drawdown of the
impoundment.
7.15. Evaluation of the stability of the reservoir
impoundment rim area in order to safeguard against reservoir
impoundment rim slides of such magnitude as to create waves capable of
overtopping the impounding structure and confirmation evaluation
of rim stability during seismic activity.
8.16. Design assumptions and analyses sufficient
to indicate that seepage in, around, through or under the impounding structure,
foundation and abutments will be reasonably and practically controlled so that
internal or external forces or results thereof will not endanger the stability and
integrity of the impounding structure. The design report shall also
include information on graded filter design.
9.17. Calculations and assumptions relative to hydraulic
and structural design of the spillway or spillways and energy dissipater
or dissipaters. Spillway capacity shall conform to the criteria of Table 1 and
4VAC50-20-52.
10.18. Provisions to ensure that the impounding
structure and appurtenances will be protected against unacceptable
deterioration or erosion due to freezing and thawing, wind, wave action,
and rain or any combination thereof.
11.19. Other pertinent design data, assumptions
and analyses commensurate with the nature of the particular impounding
structure and specific site conditions, including when required by the
director this chapter, a plan and [ water surface ]
profile of the dam break inundation [ zones zone ].
12. Erosion and sediment control plans to minimize soil
erosion and sedimentation during all phases of construction, operation and
maintenance. Projects shall be in compliance with local erosion and sediment
control ordinances.
13.20. A description of the techniques to be used
to divert stream flow during construction so as to prevent hazard to life,
health and property, including a detailed plan and procedures to maintain a
stable impounding structure during storm events, a drawing showing temporary
diversion devices, and a description of the potential impoundment during
construction. Such diversion plans shall also be in accordance with applicable
environmental laws.
14.21. A plan of for project
construction monitoring and quality control testing to confirm that
construction materials and methods performance standards meet the
design requirements set forth in the specifications.
15. A proposed schedule indicating construction sequence and
time to completion.
16.22. Plans and specifications as required by
4VAC50-20-310.
17. An emergency action plan on official forms and evidence
that a copy of such plan has been filed with the local organization for
emergency management and the State Department of Emergency Management. The plan
shall include a method of providing notification and warning to persons
downstream, other affected persons or property owners and local authorities in
the event of a flood hazard or the impending failure of the impounding
structure.
18. A proposed impoundment and impounding structure
operation and maintenance plan on official forms certified by a professional
engineer. This plan shall include a safety inspection schedule and shall place particular
emphasis on operating and maintaining the impounding structure in keeping with
the project design, so as to maintain its structural integrity and safety
during both normal and abnormal conditions which may reasonably be expected to
occur during its planned life.
C. The director or the applicant may request a conference
to facilitate review of the applicant's proposal.
D. The owner shall certify in writing that the operation
and maintenance plan as approved by the board will be adhered to during the
life of the project except in cases of unanticipated emergency requiring
departure therefrom in order to mitigate hazard to life and property. At such
time, the owner's engineer and the director shall be notified.
E. If the submission is not acceptable, the director shall
inform the applicant within 60 days and shall explain what changes are required
for an acceptable submission.
F. Within 120 days of receipt of an acceptable design
report the board shall act on the application.
23. Certification by the owner's engineer that the information provided pursuant to this subsection is true and correct in their professional judgment. Such certification shall include the engineer's signature, printed name, Virginia number, date, and the engineer's Virginia seal.
24. Owner's signature certifying receipt of the information provided pursuant to this subsection.
C. A plan of construction is a required element of a complete permit application for a Construction Permit and shall include:
1. A construction sequence with milestones.
2. Elements of the work plan that should be considered include, but are not limited to, foundation and abutment treatment, stream or river diversion, excavation and material fill processes, phased fill and compaction, testing and control procedures, construction of permanent spillway and drainage devices.
3. The erosion and sediment control plan, as approved by the local government, which minimizes soil erosion and sedimentation during all phases of construction.
4. The stormwater management plan or stormwater management facility plan, as approved by the local government, if the impounding structure is a stormwater management best management practice.
D. A Temporary Emergency Action Plan is a required element of a complete application for a Construction Permit and shall include:
1. A notification list of state and local emergency response agencies;
2. Provisions for notification of potentially affected residences and structures;
3. Construction site evacuation routes; and
4. Any other special notes particular to the project.
E. Within 120 days of receipt of a complete Construction Permit Application the board shall act on the application. If the application is not acceptable, the director shall inform the applicant within 60 days of receipt and shall explain what changes are required for an acceptable application. A complete Construction Permit Application consists of the following:
1. A final design report, submitted on the department form (Design Report for the Construction or Alteration of Virginia Regulated Impounding Structures), with attachments as needed, and certified by the owner and the owner's engineer;
2. A plan of construction that meets the requirements of subsection C of this section; and
3. A Temporary Emergency Action Plan that meets the requirements of subsection D of this section.
G.F. Prior to and during construction the owner
shall notify provide the director of with any
proposed changes from the approved design, plans, specifications, or operation
and maintenance plan of construction. Approval shall be obtained
from the director prior to the construction or installation of any changes that
will affect the stability integrity or impounding capacity of the
impounding structure.
H.G. The construction permit Construction
Permit shall be valid for the plan of construction schedule
specified in the approved design report Construction Permit
Application. The construction schedule may be amended by the director
for good cause at the request of the applicant.
I.H. Construction must commence within two years
after the permit is issued. If construction does not commence within two years
after the permit is issued, the permit shall expire, except that the applicant
may petition the board for extension of the two-year period and the board may
extend such period for good cause with an appropriately updated plan of
construction and [ temporary emergency action plan
Temporary Emergency Action Plan ].
J. The director may revoke a construction permit if any of
the permit terms are violated, or if construction is conducted in a manner
hazardous to downstream life or property. The director may order the owner to
eliminate such hazardous conditions within a period of time limited by the
order. Such corrective measures shall be at the owner's expense. The applicant
may petition the board to reissue the permit with such modifications as the
board determines to be necessary.
K. The owner's professional engineer shall advise the
director when the impounding structure may safely impound water. The director
shall acknowledge this statement within 10 days after which the impoundment may
be filled under the engineer's supervision. The director's acknowledgement
shall act as a temporary operation and maintenance certificate until an operation
and maintenance certificate has been applied for and issued in accordance with
4VAC50-20-110.
I. The board, the director, or both may take any necessary action consistent with the Dam Safety Act (§10.1-604 et seq. of the Code of Virginia) if any terms of this section or of the permit are violated, if the activities of the owner are not in accordance with the approved plans and specifications, if construction is conducted in a manner hazardous to downstream life or property, or for other cause as described in the Act.
J. Within 90 days after completion of the construction of an impounding structure, the owner shall submit:
1. A complete set of record drawings signed and sealed by a licensed professional engineer and signed by the owner:
2. A complete Record Report (Record Report for Virginia Regulated Impounding Structures) signed and sealed by a licensed professional engineer and signed by the owner that includes:
a. Project information including the name and inventory number of the structure, name of the reservoir, and whether the report is associated with a new or old structure;
b. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude;
c. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication;
d. Information on the design report, including who it was prepared by, the date of design report preparation, whether it was for new construction or for an alteration, and the permit issuance date;
e. Owner's engineer's name, firm, professional engineer Virginia number, mailing address, and business telephone number;
f. Impounding structure data including type of material (earth, concrete, masonry or other) and the following configurations:
(1) Top of [ dam impounding
structure ] (elevation);
(2) Downstream toe lowest (elevation);
(3) Height of [ dam impounding
structure ] (feet);
(4) Crest length exclusive of spillway (feet);
(5) Crest width (feet);
(6) Upstream slope (horizontal [ and
to ] vertical); and
(7) Downstream slope (horizontal [ and
to ] vertical).
g. Reservoir data including the following:
(1) Maximum capacity (acre-feet);
(2) Maximum pool (elevation);
(3) Maximum pool surface area (acres);
(4) Normal capacity (acre-feet);
(5) Normal pool (elevation);
(6) Normal pool surface area (acres); and
(7) Freeboard [ normal pool to top of dam ]
(feet).
h. Spillway data including the type, construction material,
design configuration, and invert elevation for the low level drain, the
principal spillway, and the emergency spillway; a description of the low level
drain and principal spillway including dimensions, trash guard information, and
orientation of intake and discharge to [ dam
impounding structure ] if looking downstream; and a description of
the emergency spillway including dimensions and orientation to [ dam
impounding structure ] if looking downstream;
i. Watershed data including drainage area (square miles);
type and extent of watershed development; time of concentration (hours);
routing procedure; spillway design flood used and state source; design inflow
hydrograph volume (acre-feet), peak inflow (cfs), and rainfall duration
(hours); [ and ] freeboard during passage of the
spillway design flood (feet); [ and confirmation as to whether
the impounding structure has ever been overtopped; ]
j. Impounding structure history including the date construction was completed, who it was designed by and the date, who it was built by and the date, who performed inspections and dates, description of repairs, and confirmation as to whether the impounding structure has ever been overtopped;
k. A narrative describing the impounding structure procedures for operation, maintenance, filling, emergency action plan implementation, and structure evaluation;
l. A narrative describing the hydraulic and hydrologic data on the spillway design flood, hydrologic records, flood experience, flood potential, reservoir regulation, and comments or recommendations regarding these attributes;
m. A narrative describing stability of the foundation and abutments, embankment materials, and a written evaluation of each;
n. A complete set of record drawings signed and sealed by a licensed professional engineer and signed by the owner;
o. Certification by the owner's engineer that the information provided pursuant to subdivision J 2 of this section is true and correct in their professional judgment. Such certification shall include the engineer's signature, printed name, Virginia number, date, and the engineer's Virginia seal; and
p. Owner's signature certifying receipt of the information provided pursuant to subdivision J 2 of this section.
3. Certification from the licensed professional engineer who has monitored construction of the impounding structure during construction that, to the best of the engineer's judgment, knowledge and belief, the impounding structure and its appurtenances were constructed in conformance with the plans, specifications, drawings and other requirements approved by the board;
4. Operation and Maintenance Certificate Application (Operation and Maintenance Certificate Application for Virginia Regulated Impounding Structures) in accordance with 4VAC50-20-105; and
5. Emergency Action Plan or Emergency Preparedness Plan in accordance with 4VAC50-20-175 or 4VAC50-20-177.
K. Upon completion of construction, the impoundment may be filled upon board issuance of an Operation and Maintenance Certificate.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §2.2, eff. February 1, 1989; amended, Virginia Register Volume 18, Issue 14, eff. July 1, 2002; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-80. Alterations permits.
A. Application for a permit to alter an impounding
structure in ways which would potentially affect its structural integrity shall
be made on official forms. The application shall clearly describe the proposed work
with appropriately detailed plans and specifications.
B. A. Alterations which would potentially affect
the structural integrity of an impounding structure include, but are not
limited to, changing its the height or otherwise
enlarging the dam, increasing the normal pool or principal spillway
elevation or physical dimensions, changing the elevation or physical
dimensions of the emergency spillway, conducting necessary repairs or
structural maintenance, or removing the impounding structure. [ Structural
maintenance does not include routine maintenance. ]
C. Where feasible an application for an alteration permit
shall also include plans and specifications for a device to allow for draining
the impoundment if such does not exist.
D. If the submission is not acceptable, the director shall
inform the applicant within 60 days and shall explain what changes are required
for an acceptable submission.
E. Within 120 days of receipt of an acceptable application,
the board shall act on the application.
B. An applicant for an Alteration Permit shall submit a
design report. A form for the design report [ will be
is ] available from the department (Design Report for the
Construction or Alteration of Virginia Regulated Impounding Structures). The
design report shall be prepared in accordance with 4VAC50-20-240. The design
report shall include, but not be limited to, the following information:
1. Project information including a description and benefits of the proposed alteration, name of the impounding structure, inventory number if available, name of the reservoir, and the purpose of the reservoir.
2. The hazard potential classification in conformance with Table 1 in 4VAC50-20-50.
3. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude.
4. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication.
5. Owner's engineer's name, firm, professional engineer Virginia number, mailing address, and business telephone number.
6. Impounding structure data including type of material (earth, concrete, masonry or other) and the following configurations (note both existing and design configurations for each):
a. Top of [ dam impounding
structure ] (elevation);
b. Downstream toe lowest (elevation);
c. Height of [ dam impounding
structure ] (feet);
d. Crest length exclusive of spillway (feet);
e. Crest width (feet);
f. Upstream slope (horizontal [ and
to ] vertical); and
g. Downstream slope (horizontal [ and
to ] vertical).
7. Reservoir data including the following (note both existing and design configurations for each):
a. Maximum capacity (acre-feet);
b. Maximum pool (elevation);
c. Maximum pool surface area (acres);
d. Normal capacity (acre-feet);
e. Normal pool (elevation);
f. Normal pool surface area (acres); and
g. Freeboard [ normal pool to top of dam ]
(feet).
8. Spillway data including the type, construction material, design configuration, and invert elevation for the low level drain, the principal spillway, and the emergency spillway.
9. Watershed data including drainage area (square miles); type and extent of watershed development; time of concentration (hours); routing procedure; spillway design flood used and state source; design inflow hydrograph volume (acre-feet), peak inflow (cfs), and rainfall duration (hours); and freeboard during passage of the spillway design flood (feet).
10. Evidence that the local government has been notified of the alteration and repair plan.
11. Plans and specifications as required by 4VAC50-20-310.
The plan view of the [ dam impounding structure ]
site should represent all significant structures and improvements that
illustrate the location of all proposed work.
12. A report of the geotechnical investigations of the foundation soils, bedrock, or both in the areas affected by the proposed alterations and of the materials to be used to alter the impounding structure.
13. Design assumptions and analyses sufficient to indicate that the impounding structure will be stable during the alteration of the impounding structure under all conditions of reservoir operations.
14. Calculations and assumptions relative to design of the improved spillway or spillways, if applicable.
15. Provisions to ensure that the impounding structure and appurtenances during the alteration will be protected against unacceptable deterioration or erosion due to freezing and thawing, wind, wave action and rain or any combination thereof.
16. Other pertinent design data, assumptions and analyses
commensurate with the nature of the particular impounding structure and
specific site conditions, including when required by this chapter, a plan and
[ water surface ] profile of the dam break inundation
[ zones zone ].
17. If applicable, a description of the techniques to be used to divert stream flow during alteration work so as to prevent hazard to life, health and property, including a detailed plan and procedures to maintain a stable impounding structure during storm events, a drawing showing temporary diversion devices, and a description of the potential impoundment during the alteration. Such diversion plans shall be in accordance with the applicable environmental laws.
18. A plan for project construction monitoring and quality control testing to confirm that materials used in the alteration work and that performance standards meet the design requirements set forth in the specifications.
19. Certification by the owner's engineer that the information provided pursuant to this subsection is true and correct in their professional judgment. Such certification shall include the engineer's signature, printed name, Virginia number, date, and the engineer's Virginia seal.
20. Owner's signature certifying receipt of the information provided pursuant to this subsection.
C. A plan of construction is a required element of complete permit application and shall include:
1. A construction sequence with milestones.
2. Elements of the work plan that should be considered include, but are not limited to, foundation and abutment treatment, excavation and material fill processes, phased fill and compaction, testing and control procedures, construction of permanent spillway and drainage devices, if applicable.
3. The erosion and sediment control plan, as approved by the local government, which minimizes soil erosion and sedimentation during all phases of construction.
D. Within 120 days of receipt of a complete Alteration Permit Application, the board shall act on the application. If the application is not acceptable, the director shall inform the applicant within 60 days of receipt and shall explain what changes are required for an acceptable application. A complete Alteration Permit Application consists of the following:
1. A final design report with attachments as needed, and certified by the owner;
2. A plan of construction that meets the requirements of subsection C of this section;
3. Any necessary interim provisions to the current Emergency Action Plan or Emergency Preparedness Plan. Interim provisions shall be submitted to the local organization for emergency management, the Virginia Department of Emergency Management, and the department; and
4. If the owner is requesting the deregulation of an impounding structure, the application shall specify whether the impounding structure is to be removed so that the impounding structure is incapable of storing water, either temporarily or permanently; or whether the impounding structure is to be altered in such a manner that either the height or storage capacity of the impounding structure causes the impounding structure to be of less than regulated size.
E. During the alteration work, the owner shall provide the director with any proposed changes from the approved design, plans, specifications, or a plan of construction. Approval shall be obtained from the director prior to the alteration or installation of any changes that will affect the integrity or impounding capacity of the impounding structure.
F. The Alteration Permit shall be valid for the construction sequence with milestones specified in the approved Alteration Permit Application.
G. Work identified in the Alteration Permit must commence within the time frame identified in the Alteration Permit. If work does not commence within the prescribed time frame, the permit shall expire, except that the applicant may petition the board for extension of the prescribed time frame and the board may extend such period for good cause with an updated construction sequence with milestones.
H. The board, the director, or both may take any necessary action consistent with the Dam Safety Act (§10.1-604 et seq. of the Code of Virginia) if any terms of this section or of the permit are violated, if the activities of the owner are not in accordance with the approved plans and specifications, if the alteration is conducted in a manner hazardous to downstream life or property, or for other cause as described in the Act.
I. Within 90 days after completion of the alteration of an
impounding structure, the owner shall submit a complete Record Report. A form
for the Record Report [ will be is ] available
from the department (Record Report for Virginia Regulated Impounding
Structures). The Record Report [ shall be ] signed and
sealed by a licensed professional engineer and signed by the owner [ and
shall be sent ] to the department indicating [ that ]
the modifications made to the structural features of the impounding
structure [ have been completed ]. This report is not
required when the Alteration Permit has been issued for the removal of an
impounding structure. The Record Report shall include the following:
[ a. 1. ] Project information
including the name and inventory number of the structure, name of the
reservoir, and whether the report is associated with a new or old structure;
[ b. 2. ] Location of the
impounding structure including the city or county, number of feet or miles upstream
or downstream of a highway and the highway number, name of the river or the
stream, and the latitude and longitude;
[ c. 3. ] Owner's name or
representative if corporation, mailing address, residential and business
telephone numbers, and other means of communication;
[ d. 4. ] Information on the
design report, including who it was prepared by, the date of design report
preparation, whether it was for new construction or for an alteration, and the
permit issuance date;
[ e. 5. ] Owner's engineer's name,
firm, professional engineer Virginia number, mailing address, and business
telephone number;
[ f. 6. ] Impounding
structure data including type of material (earth, concrete, masonry or other)
and the following configurations:
[ (1) a. ] Top of
[ dam impounding structure ] (elevation);
[ (2) b. ] Downstream toe
lowest (elevation);
[ (3) c. ] Height of
[ dam impounding structure ] (feet);
[ (4) d. ] Crest length
exclusive of spillway (feet);
[ (5) e. ] Crest width
(feet);
[ (6) f. ] Upstream slope (horizontal
[ and to ] vertical); and
[ (7) g. ] Downstream slope
(horizontal [ and to ] vertical).
[ g. 7. ] Reservoir data
including the following:
[ (1) a. ] Maximum capacity
(acre-feet);
[ (2) b. ] Maximum pool
(elevation);
[ (3) c. ] Maximum pool surface
area (acres);
[ (4) d. ] Normal capacity
(acre-feet);
[ (5) e. ] Normal pool
(elevation);
[ (6) f. ] Normal pool
surface area (acres); and
[ (7) g. ] Freeboard
[ normal pool to top of dam ] (feet).
[ h. 8. ] Spillway data
including the type, construction material, design configuration, and invert
elevation for the low level drain, the principal spillway, and the emergency
spillway; a description of the low level drain and principal spillway including
dimensions, trash guard information, and orientation of intake and discharge to
[ dam impounding structure ] if looking
downstream; and a description of the emergency spillway including dimensions
and orientation to [ dam impounding structure ]
if looking downstream;
[ i. 9. ] Watershed data
including drainage area (square miles); type and extent of watershed
development; time of concentration (hours); routing procedure; spillway design
flood used and state source; design inflow hydrograph volume (acre-feet), peak
inflow (cfs), and rainfall duration (hours); and freeboard during passage of
the spillway design flood (feet);
[ j. 10. ] Impounding
structure history including the date construction was completed, who it was
designed by and the date, who it was built by and the date, who performed
inspections and dates, description of repairs, and confirmation as to whether
the impounding structure has ever been overtopped;
[ k. 11. ] A narrative
describing the impounding structure procedures for operation, maintenance,
emergency action plan implementation, and structure evaluation;
[ l. 12. ] A narrative
describing the hydraulic and hydrologic data on the spillway design flood,
hydrologic records, flood experience, flood potential, reservoir regulation,
and comments or recommendations regarding these attributes;
[ m. 13. ] A narrative
describing stability of the foundation and abutments, embankment materials, and
a written evaluation of each;
[ n. 14. ] A complete set of
record drawings signed and sealed by a licensed professional engineer and
signed by the owner;
[ o. 15. ] Certification by
the owner's engineer that the information provided pursuant to [ subdivision
I 2 of this section this subsection ] is true and
correct in their professional judgment. Such certification shall include the
engineer's signature, printed name, Virginia number, date, and the engineer's
Virginia seal; and
[ p. 16. ] Owner's signature
certifying receipt of the information provided pursuant to [ subdivision
I 2 of this section this subsection ] .
J. For altered impounding structures, a certification from a licensed professional engineer who has monitored the alteration of the impounding structure that, to the best of the engineer's judgment, knowledge, and belief, the impounding structure and its appurtenances were altered in conformance with the plans, specifications, drawings and other requirements approved by the board.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §2.3, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-90. Transfer of permits.
A. Prior to the transfer of ownership of a permitted
impounding structure the permittee shall notify the director in writing and the
new owner shall file a transfer application on official forms notification
with the department. A form for the transfer notification [ will
be is ] available from the department (Transfer of
Impounding Structure Notification form Past Owner to New Owner). The new
owner shall amend the existing permit application as necessary and shall
certify to the director that he is aware of and will comply with all of the
requirements and conditions of the permit.
B. The [ Transfer Notification
transfer notification ] shall include the following required
information:
1. Project information including the name and inventory number of the structure, name of the reservoir, and impoundment hazard classification;
2. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude;
3. Type of certificates and permits to be transferred including effective date and expiration date of all certificates and permits;
4. Past owner's name, mailing address, and residential and business telephone numbers;
5. New owner's name, mailing address, and residential and business telephone numbers;
6. Request to transfer certification statement signed and dated by the past owner;
7. Certification of compliance with permit or certificate with all said terms and conditions signed and dated by the new owner; and
8. Contact information updates for Emergency Action Plan or
Emergency Preparedness Plan provided by the new owner. Such updates shall
include the name, mailing address, and residential and business telephone
numbers for the [ dam impounding structure ]
owner, [ dam impounding structure ] operator,
rainfall and staff gage observer, and alternate observer.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §2.4, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part III
Certificate Requirements
4VAC50-20-100. Operation and maintenance certificates. (Repealed.)
A. A Class I Operation and Maintenance Certificate is
required for a Class I Hazard potential impounding structure. The certificate shall
be for a term of six years. It shall be updated based upon the filing of a new
reinspection report certified by a professional engineer every two years.
B. A Class II Operation and Maintenance Certificate is
required for a Class II Hazard potential impounding structure. The certificate
shall be for a term of six years. It shall be updated based upon the filing of
a new reinspection report certified by a professional engineer every three
years.
C. A Class III Operation and Maintenance Certificate is required
for a Class III Hazard potential impounding structure. The certificate shall be
for a term of six years.
D. The owner of a Class I, II or III impounding structure
shall provide the director an annual owner's inspection report on official
forms in years when no professional reinspection is required and may be done by
the owner or his representative.
E. If an Operation and Maintenance Certificate is not
updated as required, the board shall take appropriate enforcement action.
F. The owner of a Class I, II or III impounding structure
shall apply for the renewal of the six year operation and maintenance
certificate 90 days prior to its expiration in accordance with 4VAC50-20-120 of
this chapter.
G. A Class IV impounding structure will not require an
operation and maintenance certificate. An inventory report is to be prepared as
provided in 4VAC50-20-120 B and filed by the owner on a six-year interval, and
an owners inspection report filed annually.
H. The owner of any impounding structure, regardless of its
hazard classification, shall notify the board immediately of any change in
either cultural features downstream from the impounding structure or of any
change in the use of the area downstream that would present hazard to life or
property in the event of failure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.1, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part III
Certificate Requirements
4VAC50-20-105. Regular Operation and Maintenance Certificates.
A. A Regular Operation and Maintenance Certificate is required for an impounding structure. Such six-year certificates shall include the following based on hazard classification:
1. High Hazard Potential Regular Operation and Maintenance Certificate;
2. Significant Hazard Potential Regular Operation and Maintenance Certificate; or
3. Low Hazard Potential Regular Operation and Maintenance Certificate.
B. The owner of an impounding structure shall apply for the renewal of the six-year Regular Operation and Maintenance Certificate 90 days prior to its expiration. If a Regular Operation and Maintenance Certificate is not renewed as required, the board shall take appropriate enforcement action.
C. Any owner of an impounding structure that does not have
a Regular Operation and Maintenance Certificate or any owner renewing a Regular
Operation and Maintenance Certificate shall file an Operation and Maintenance
Certificate Application. A form for the application [ will be
is ] available from the department (Operation and Maintenance
Certificate Application for Virginia Regulated Impounding Structures). Such
application shall be signed by the owner and signed and sealed by a licensed
professional engineer. The following information shall be submitted on or with
the application:
1. The application shall include the following required information:
a. The name of structure and inventory number;
b. The proposed hazard potential classification;
c. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication;
d. An operating plan and schedule including a narrative on the operation of control gates and spillways and the impoundment drain;
e. For earthen embankment [ dams
impounding structures ] , a maintenance plan and schedule for the
embankment, principal spillway, emergency spillway, low-level outlet,
impoundment area, downstream channel, and staff gages;
f. For concrete [ dams impounding
structures ] , a maintenance plan and schedule for the upstream
face, downstream face, crest of dam, galleries, tunnels, abutments, spillways,
gates and outlets, and staff gages;
g. An inspection schedule for operator inspection, maintenance inspection, technical safety inspection, and overtopping situations;
h. A schedule including the rainfall amounts, emergency spillway flow levels or storm event that initiates the Emergency Action or Preparedness Plan and the frequency of observations;
i. A statement as to whether or not the current hazard
potential classification for the [ dam impounding
structure ] is appropriate and whether or not additional work is
needed to make an appropriate hazard potential designation;
j. For newly constructed or recently altered impounding structures, a certification from a licensed professional engineer who has monitored the construction or alteration of the impounding structure that, to the best of the engineer's judgment, knowledge, and belief, the impounding structure and its appurtenances were constructed or altered in conformance with the plans, specifications, drawings and other requirements approved by the board;
k. Certification by the owner's engineer that the Operation and Maintenance Certificate Application information provided pursuant to subdivision 1 of this subsection is true and correct in their professional judgment. Such certification shall include the engineer's signature, printed name, Virginia number, date, and the engineer's Virginia seal; and
l. Owner's signature certifying the Operation and Maintenance Certificate Application information provided pursuant to subdivision 1 of this subsection and that the operation and maintenance plan and schedule shall be conducted in accordance with this chapter.
2. An Inspection Report (Annual Inspection Report for Virginia Regulated Impounding Structures) in accordance with subsection E of this section;
3. An Emergency Action Plan in accordance with 4VAC50-20-175 or an Emergency Preparedness Plan in accordance with 4VAC50-20-177 and evidence that the required copies of such plan have been submitted to the local organization for emergency management and the Virginia Department of Emergency Management; and
4. Any additional analysis determined necessary by the director, the board or the owner's engineer to address public safety concerns. Such additional analysis may include, but not be limited to, seismic stability, earthen spillway integrity, adequate freeboard allowance, stability assessment of the impoundment's foundation, potential liquefaction of the embankment, overturning or sliding of a concrete structure and other structural stress issues.
D. If the Operation and Maintenance Certificate Application submittal is found to be not complete, the director shall inform the applicant within 30 days and shall explain what changes are required for an acceptable submission. Within 60 days of receipt of a complete application the board shall act upon the application. Upon finding that the impounding structure as currently operating is in compliance with this chapter, the board shall issue a Regular Operation and Maintenance Certificate. Should the board find that the impounding structure as currently operating is not in compliance with this chapter, the board may deny the permit application or issue a Conditional Operation and Maintenance Certificate in accordance with 4VAC50-20-150.
E. Inspections shall be performed on an impounding structure annually.
1. Inspection Reports (Annual Inspection Report for Virginia Regulated Impounding Structures) signed and sealed by a licensed professional engineer shall be submitted to the department in accordance with the following schedule:
a. For a High Hazard Potential impounding structure, every two years,
b. For a Significant Hazard Potential impounding structure, every three years,
c. For a Low Hazard Potential impounding structure, every six years.
In years when an Inspection Report signed and sealed by a licensed professional engineer is not required, an owner shall submit the Annual Inspection Report for Virginia Regulated Impounding Structures.
2. The Inspection Report shall include the following required information:
a. Project information including the name and inventory number of structure, name of the reservoir, and purpose of the reservoir;
b. City or county where the impounding structure is located;
c. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication;
d. Owner's engineer's name, firm, professional engineer Virginia number, mailing address, and business telephone number;
e. Inspection observation of the impounding structure including the following:
(1) Earthen embankment information including any embankment alterations; erosion; settlement, misalignments or cracks; seepage and seepage flow rate and location;
(2) Upstream slope information including notes on woody vegetation removed, rodent burrows discovered, and remedial work performed;
(3) Intake structure information including notes on deterioration of concrete structures, exposure of rebar reinforcement, need to repair or replace trash rack, any problems with debris in the reservoir, and whether the drawdown valve operated;
(4) Abutment contacts including notes on seepage and seepage flow rate and location;
(5) Earthen emergency spillway including notes on obstructions to flow and plans to correct, rodent burrows discovered, and deterioration in the approach or discharge channel;
(6) Concrete emergency spillway including notes on the deterioration of the concrete, exposure of rebar reinforcement, any leakage below concrete spillway, and obstructions to flow and plans to correct;
(7) Downstream slope information including notes on woody vegetation removed, rodent burrows discovered, whether seepage drains are working, and any seepage or wet areas;
(8) Outlet pipe information including notes on any water
flowing outside of discharge pipe through the [ dam
impounding structure ] and a description of any reflection or
damage to the pipe;
(9) Stilling basin information including notes on the deterioration of the concrete, exposure of rebar reinforcement, deterioration of the earthen basin slopes, repairs made, and any obstruction to flow;
(10) Gates information including notes on gate malfunctions or repairs, corrosion or damage, and whether any gates were operated and if so how often and to what extreme;
(11) Reservoir information including notes on new developments upstream of the dam, slides or erosion of lake banks, and general comments to include silt, algae, or other influence factors;
(12) Instruments information including any reading of instruments and any installation of new instruments; and
(13) General information including notes on new development
in the downstream [ floodplain dam break inundation
zone ] that would impact hazard classification [ or
spillway design flood requirements ], the maximum stormwater
discharge or peak elevation during the previous year, whether general
maintenance was performed and when, and actions that need to be completed
before the next inspection.
f. Evaluation rating of the [ dam
impounding structure ] and appurtenances (excellent, good, or
poor), general comments, and recommendations;
g. Certification by the owner and date of inspection; and
h. Certification and seal by the owner's engineer and date of inspection, as applicable.
F. The owner of an impounding structure shall notify the department immediately of any change in the use of the area downstream that would impose hazard to life or property in the event of failure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-110. Operation and maintenance certificate for
newly constructed impounding structures. (Repealed.)
A. Within 180 days after completion of the construction of
an impounding structure, the owner shall submit:
1. A complete set of as-built drawings certified by a
professional engineer and an as-built report on official forms.
2. A copy of a certificate from the professional engineer
who has inspected the impounding structure during construction certifying that,
to the best of his judgment, knowledge and belief, the impounding structure and
its appurtenances were constructed in conformance with the plans,
specifications, drawings and other requirements approved by the board.
3. A copy of the operation and maintenance plan and
emergency action plan submitted with the design report including any changes
required by the director.
B. If the director finds that the operation and maintenance
plan or emergency action plan is deficient, he shall return it to the owner within
60 days with suggestions for revision.
C. Within 60 days of receipt of the items listed in
subsection A above, if the board finds that adequate provision has been made
for the safe operation and maintenance of the impounding structure, the board
shall issue an operation and maintenance certificate.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.2, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-120. Operation and maintenance certificates for
existing impounding structures. (Repealed.)
A. Any owner of an impounding structure other than a Class
IV impounding structure which has already filed an inventory report that does not
have an operation and maintenance certificate or any owner renewing an
operation and maintenance certificate shall file an application with the board.
B. The application for an operation and maintenance
certificate shall be on official forms and shall include:
1. A reinspection report for Class I and II impounding
structures. The reinspection report shall include an update of conditions of
the impounding structure based on a previous safety inspection as required by
the board, a previous reinspection report or an as-built report.
2. An inventory report for Class III impounding structures.
The inventory report shall include:
a. The name and location of the impounding structure and
the name of the owner.
b. The description and dimensions of the impounding
structure, the spillways, the reservoir and the drainage area.
c. The history of the impounding structure which shall
include the design, construction, repairs, inspections and whether the
structure has been overtopped.
d. Observations of the condition of the impounding
structure, reservoir, and upstream and downstream areas.
e. Any changes in the impounding structure, reservoir, and
upstream and downstream areas.
f. Recommendations for remedial work.
3. An impoundment and impounding structure operation and
maintenance plan certified by a professional engineer. This plan shall place
particular emphasis on operating and maintaining the impounding structure in
keeping with the project design in such manner as to maintain its structural
integrity and safety during both normal and abnormal conditions which may
reasonably be expected to occur during its planned life. The safety inspection
report required by the board should be sufficient to serve as the basis for the
operation and maintenance plan for a Class I and Class II impounding structure.
For a Class III impounding structure, the operation and maintenance plan shall
be based on the data provided in the inventory report.
4. An emergency action plan and evidence that a copy of such
plan has been filed with the local organization for emergency management and
the State Department of Emergency Management. The plan shall include a method
of providing notification and warning to persons downstream, other affected
persons or property owners and local authorities in the event of a flood hazard
or the impending failure of the impounding structure.
C. The owner shall certify in writing that the operation
and maintenance plan approved by the board will be adhered to during the life
of the project except in cases of emergency requiring departure therefrom in
order to mitigate hazard to life and property, at which time the owner's
engineer and the director shall be notified.
D. If the director finds that the operation and maintenance
plan or emergency action plan is deficient, he shall return it to the owner
within 60 days with suggestions for revision.
E. Within 60 days of receipt of an acceptable application
if the board finds that adequate provision has been made for the safe operation
and maintenance of the impounding structure, the board shall issue an operation
and maintenance certificate.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.3, eff. February 1, 1989; repealed, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-125. Delayed effective date for Spillway Design Flood requirements for impounding structures.
A. If an impounding structure has been determined to have
an adequate spillway capacity prior to [ the effective date of
these regulations September 26, 2008, ] and is currently
operating under a Regular Operation and Maintenance Certificate, but will now
require spillway modifications due to changes in these regulations, the owner
shall submit to the board an Alteration Permit Application in accordance with
4VAC50-20-80 to address spillway capacity at the time of the expiration of
their Regular Operation and Maintenance Certificate or [ within
three years of the effective date of these regulations, by September
26, 2011, ] whichever is later. The Alteration Permit Application
shall contain a construction sequence with milestones for completing the
necessary improvements within five years of Alteration Permit issuance. The
board may approve an extension of the prescribed time frame for good cause.
Should the owner be able to demonstrate that no spillway capacity change is
necessary, the impounding structure may be found to be in compliance with this
chapter.
B. In accordance with 4VAC50-20-105, the owner shall submit the Operation and Maintenance Certificate Application (Operation and Maintenance Certificate Application for Virginia Regulated Impounding Structures), the Emergency Action Plan or Emergency Preparedness Plan, and the Inspection Report (Annual Inspection Report for Virginia Regulated Impounding Structures) 90 days prior to the expiration of the Regular Operation and Maintenance Certificate.
C. If circumstances warrant more immediate repairs to the impounding structure, the board may direct alterations to the spillway to be completed sooner.
D. During this delay period, owners are required to address other deficiencies that may exist that are not related to the spillway design flood.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-130. Existing impounding structures constructed
prior to July 1, 1982. (Repealed.)
A. Many existing impoundment structures were designed and
constructed prior to the enactment of the Dam Safety Act, and may not satisfy
current criteria for new construction. The board may issue an operation and
maintenance certificate for such structures provided that:
1. Operation and maintenance is determined by the director
to be satisfactory and up to date;
2. Annual owner's inspection reports have been filed with
and are considered satisfactory by the director;
3. The applicant proves in accordance with the current
design procedures and references of 4VAC50-20-320 to the satisfaction of the
board that the impounding structure as designed, constructed, operated and
maintained does not pose an unreasonable hazard to life and property; and
4. The owner satisfies all special requirements imposed by
the board.
B. When appropriate with existing impounding structures
only, the spillway design flood requirement may be reduced by the board to the
spillway discharge at which dam failure will not significantly increase the
downstream hazard existing just prior to dam failure provided that the
conditions of 4VAC50-20-130 A have been met.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.4, eff. February 1, 1989; repealed, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-140. Existing impounding structures constructed
after July 1, 1982. (Repealed.)
The board may issue an operation and maintenance
certificate for an impounding structure having a construction permit issued
after July 1, 1982, and shall not require upgrading to meet new more stringent
criteria unless the board determines that the new criteria must be applied to
prevent an unreasonable hazard to life or property.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.5, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-150. Conditional operation and maintenance certificate.
A. During the review of any operation Operation
and maintenance application Maintenance Certificate Application (Operation
and Maintenance Certificate Application for Virginia Regulated Impounding
Structures) completed in accordance with 4VAC50-20-105 should the director
determine that the impounding structure has nonimminent deficiencies of
a nonimminent danger category, the director may recommend that the board
issue a conditional operation Conditional Operation and maintenance
certificate Maintenance Certificate.
B. The conditional operation Conditional Operation
and maintenance certificate Maintenance Certificate for Class
I, II and III High, Significant, and Low Hazard Potential impounding
structures shall be for a maximum term of two years. This certificate will
allow the owner to continue normal operation and maintenance of the impounding
structure, and shall require that the owner correct the deficiencies on a
schedule [ determined approved ] by the director
board.
C. A conditional certificate Conditional Certificate
may be renewed extended in accordance with the procedures of 4VAC50-20-120
4VAC50-20-155 provided that annual owner inspection reports Inspection
Reports (Annual Inspection Report for Virginia Regulated Impounding Structures)
are on file, and the board determines that the owner is proceeding with the
necessary corrective actions.
D. Once the deficiencies are corrected, the board shall issue an
operation a Regular Operation and maintenance certificate Maintenance
Certificate based upon any required revisions to the original
application the impounding structure's meeting the requirements of
4VAC50-20-105.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.6, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-155. Extension of Operation and Maintenance Certificates.
The board may extend an Operation and Maintenance Certificate for impounding structures provided that the owner submits a written request justifying an extension, the amount of time needed to comply with the requirements set out in the current Operation and Maintenance Certificate, and any required fees. The owner must have demonstrated substantial and continual progress towards meeting the requirements [ of the certificate in order to receive an extension ] .
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-160. Additional operation and maintenance requirements.
A. The owner of an impounding structure shall not, through action or inaction, cause or allow such structure to impound water following receipt of a written report from the owner's engineer that the impounding structure will not safely impound water.
B. In accordance with §10.1-609.2 of the Code of Virginia,
[ dam impounding structure ] owners shall not
permit the growth of trees and other woody vegetation and shall remove any such
vegetation from the slopes and crest of embankments and the emergency spillway
area, and within a distance of 25 feet from the toe of the embankment and
abutments of the dam.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.7, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-165. Agricultural exemption.
A. Impounding structures operated primarily for agricultural purposes that are less than 25 feet in height or that create a maximum impoundment capacity smaller than 100 acre-feet are exempt from the Impounding Structure Regulations.
B. An owner covered by an agricultural exemption pursuant to §10.1-604 of the Code of Virginia and 4VAC50-20-30 may validate such exemption by submitting an Agricultural Exemption Report (Agricultural Exemption Report for Impounding Structures). The Agricultural Exemption Report shall include the following information:
1. Project information including the name and inventory number of the structure and name of the reservoir;
2. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude;
3. Owner's name or representative if corporation, mailing address, residential and business telephone numbers, and other means of communication;
4. The impounding structure height in feet and the maximum impounding capacity in acre-feet;
5. A list of the agricultural functions for which the impoundment supplies water;
6. The date of validation; and
7. The owner's signature validating that the impoundment is operated primarily for agricultural purposes and is exempt from the regulations.
C. The Agricultural Exemption Report may be verified by the
department through a [ possible ] site visit.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-170. Transfer of certificates.
A. Prior to the transfer of ownership of an impounding
structure the certificate holder shall notify the director in writing and the
new owner shall file a transfer application on official forms notification
with the department. A form for the transfer notification [ will
be is ] available from the department (Transfer of
Impounding Structure Notification from Past Owner to New Owner). The new
owner may elect to continue the current existing operation and
maintenance certificate for the remaining term or he may apply for a new
certificate in accordance with 4VAC50-20-120 4VAC50-20-105. If
the owner elects to continue the existing certificate, he shall amend
the existing certificate application as necessary and shall certify to the
director that he is aware of and will comply with all of the requirements and
conditions of the certificate.
B. The [ Transfer Notification
transfer notification ] shall include the following required
information:
1. Project information including the name and inventory number of the structure, name of the reservoir, and impoundment hazard classification;
2. Location of the impounding structure including the city or county, number of feet or miles upstream or downstream of a highway and the highway number, name of the river or the stream, and the latitude and longitude;
3. Type of certificates and permits to be transferred including effective date and expiration date of all certificates and permits;
4. Past owner's name, mailing address, and residential and business telephone numbers;
5. New owner's name, mailing address, and residential and business telephone numbers;
6. Request to transfer certification statement signed and dated by the past owner;
7. Certification of compliance with permit or certificate with all said terms and conditions signed and dated by the new owner; and
8. Contact information updates for Emergency Action Plan or
Emergency Preparedness Plan provided by the new owner. Such updates shall
include the name, mailing address, and residential and business telephone
numbers for the [ dam impounding structure ]
owner, [ dam impounding structure ] operator,
rainfall and staff gage observer, and alternate observer.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §3.8, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-175. Emergency Action Plan (EAP) for High and
Significant Hazard Potential [ Dams impounding
structures ] .
A. In order to protect life during potential emergency
conditions at [ a dam an impounding structure ]
, and to ensure effective, timely action is taken should [ a
dam an impounding structure ] emergency occur, an EAP
shall be required for each High and Significant Hazard Potential impounding
structure. The EAP shall be coordinated with the Department of Emergency
Management in accordance with §44-146.18 of the Code of Virginia. The EAP
required by these regulations shall be incorporated into local and
interjurisdictional emergency plans pursuant to §44-146.19 of the Code of
Virginia.
B. It is the [ dam impounding
structure ] owner's responsibility to develop, maintain, exercise,
and implement a site-specific EAP.
C. An EAP shall be submitted every six years. The EAP shall be submitted with the owner's submittal of their Regular Operation and Maintenance Certificate application (Operation and Maintenance Certificate Application for Virginia Regulated Impounding Structures).
D. The owner shall update [and resubmit ] the
EAP immediately upon becoming aware of necessary changes to keep the EAP
workable. Should [ a dam an impounding structure ]
be reclassified, an EAP in accordance with this section shall be submitted.
E. A drill shall be conducted annually for each high or
significant hazard impounding structure. To the extent practicable, the drill
should include a face-to-face meeting with the local emergency management
agencies responsible for any necessary evacuations to review the EAP and ensure
the local emergency management agencies understand the actions required during
an emergency. A table-top exercise shall be conducted once every [ three six
] years [ ,although more frequent table-top exercises are encouraged ]
. [ Drills and table-top exercises for multiple impounding
structures may be performed in combination if the involved parties are the
same. ] Owners shall certify to the department annually that a
drill, a table-top exercise, or both has been completed [ ,
provide a critique of the exercise or exercises ] and
[ provide ] any revisions or updates to the EAP or a
statement that no revisions or updates are needed.
F. [ Dam Impounding structure ]
owners shall test existing monitoring, sensing, and warning equipment at
remote or unattended [ dams impounding structures ]
at least twice per year [ or as performed by the Virginia
Department of Emergency Management pursuant to §10.1-609.1 of the Code of
Virginia ] and maintain a record of such tests.
G. An EAP shall contain the following seven basic elements unless otherwise specified in this subsection.
1. Notification chart. A notification chart shall be included
for all classes of [ dams impounding structures ]
that shows who is to be notified, by whom, and in what priority. The
notification chart shall include contact information providing 24-hour
telephone coverage for all responsible parties [ including, but not
limited to, the impounding structure operator or manager, state and local
emergency management officials, local police or sheriffs' departments, and the
owner's engineer ] . [ The notification chart shall
also identify the process by which downstream property owners will be notified,
and what party or parties will be responsible for making such notifications. ]
2. Emergency Detection, Evaluation, and Classification. The
EAP shall include a discussion of the procedures for timely and reliable detection,
evaluation, and classification of emergency situations considered to be
relevant to the project setting and impounding features. Each relevant
emergency situation is to be documented to provide an appropriate course of
action based on the urgency of the situation. Where appropriate, situations
should address [ dam breaks impounding structure
failures ] that are imminent or in progress, a situation where the
potential for [ dam impounding structure ] failure
is rapidly developing, and a situation where the threat is slowly developing.
3. Responsibilities. The EAP shall specify responsibilities
for EAP-related tasks. The EAP shall also clearly designate the responsible
party for making the decision that an emergency condition no longer exists at
the [ dam impounding structure ]. The EAP
shall include procedures and the responsible parties for notifying to the
extent possible any known local occupants, owners, or lessees of downstream
properties potentially impacted by the [ dam's
impounding structure's ] failure.
4. Preparedness. The EAP shall include a section that describes preparedness actions to be taken both before and following development of emergency conditions.
5. Dam Break Inundation Maps. The EAP shall include dam break inundation maps developed in accordance with 4VAC50-20-54.
6. Appendices. The appendices shall contain information that
supports and supplements the material used in the development and maintenance
of the EAP such as analyses of [ dam break
impounding structure failure ] floods; plans for training, exercising,
updating, and posting the EAP; and other site-specific concerns.
7. Certification. [ The EAP shall include a
section that is signed by all parties with assigned responsibilities in the EAP
pursuant to this subdivision 3 of this subsection, where they indicate their
receipt of the EAP. The EAP shall include a section that identifies
all parties with assigned responsibilities in the EAP pursuant to subdivision 3
of this subsection. This will include certification that the EAP has been
received by these parties. ] The preparer's name, title, and
contact information shall be printed in this section. The preparer's signature
shall also be included in the certification section. The local organization for
emergency management shall provide the owner and the department with any
deficiencies they may note.
H. The development of the EAP shall be coordinated with all
entities, jurisdictions, and agencies that would be affected by [ a
dam an impounding structure ] failure or that have
statutory responsibilities for warning, evacuation, and postflood actions.
Consultation with state and local emergency management officials at appropriate
levels of management responsible for warning and evacuation of the public shall
occur to ensure that there is awareness of their individual and group
responsibilities. The owner shall also coordinate with the local organization
for emergency management to identify properties that upon failure of the
impounding structure would result in economic impacts.
I. The EAP, or any updates to an existing EAP, shall be submitted to the department, the local organization for emergency management, and the Virginia Department of Emergency Management. Two copies shall be provided to the department.
J. The following format shall be used as necessary to address the requirements of this section.
Title Page/Cover Sheet
Table of Contents
I. Certifications
II. Notification Flowchart
III. Statement of Purpose
IV. Project Description
V. Emergency Detection, Evaluation, and Classification
VI. General Responsibilities Under the EAP
A. [ Dam Impounding
Structure] Owner Responsibilities
B. Responsibility for Notification
C. Responsibility for Evacuation
D. Responsibility for Termination and Follow-Up
E. EAP Coordinator Responsibility
VII. Preparedness
VIII. Inundation Maps
IX [ . ] Appendices
A. Investigation and Analyses of [ Dam break
Impounding Structure Failure ] Floods
B. Plans for Training, Exercising, Updating, and Posting the EAP
C. Site-Specific Concerns
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-177. Emergency Preparedness Plan for Low Hazard
[ Dams impounding structures ] .
[ A. ] Low Hazard [ Dams
impounding structures ] shall provide information for emergency preparedness
to the department, the local organization for emergency management and the
Virginia Department of Emergency Management. A form for the submission
[ will be is ] available from the department
(Emergency Preparedness Plan for Low Hazard Virginia Regulated Impounding
Structures). The information shall include, but not be limited, to the
following:
1. Name of the impounding structure, inventory number, city or county, latitude, and longitude;
2. Owner's name, mailing address, residential and business telephone numbers, and other means of communication. Contact information shall provide for 24-hour telephone contact capability;
3. [ Dam Impounding structure ]
operator's name, mailing address, residential and business telephone
numbers, and other means of communication. Contact information shall provide
for 24-hour telephone contact capability;
4. Rainfall and staff gage observer's name, mailing address, residential and business telephone numbers, and other means of communication. Contact information shall provide for 24-hour telephone contact capability;
5. Contact information for alternate operator and alternate rainfall and staff gage observer, if applicable;
6. Contact information for the local dispatch center nearest
[ dam impounding structure ] including
address and 24-hour telephone number;
7. City or county emergency services coordinator's name, mailing address, residential and business telephone numbers, and other means of communication;
8. A procedure and the responsible parties for notifying to
the extent possible any known local occupants, owners, or lessees of downstream
properties potentially impacted by the [ dam's
impounding structure's ] failure;
9. A discussion of the procedures for timely and reliable detection, evaluation, and classification of emergency situations considered to be relevant to the project setting and impounding features. Each relevant emergency situation is to be documented to provide an appropriate course of action based on the urgency of the situation;
10. A simple dam break inundation map acceptable to the
director, demonstrating the general inundation that would result from
[ a dam an impounding structure ] failure.
Such maps required pursuant to this section do not require preparation by a
professional licensed engineer; however, maps prepared by a licensed
professional engineer are preferred;
11. Identification of public roads downstream noting the
highway number and distance below the [ dam
impounding structure ]. If roads exist, contact information for the
resident Virginia Department of Transportation engineer or city or county
engineer including address and 24-hour telephone numbers;
12. Amount of rainfall that will initiate a Stage II Condition in inches per six hours, inches per 12 hours, and inches per 24 hours and a Stage III Condition in inches per six hours, inches per 12 hours, and inches per 24 hours;
13. Amount of flow in the emergency spillway that will initiate a Stage II Condition in feet (depth of flow) and a Stage III Condition in feet (depth of flow);
14. Staff gage location and description; the frequency of
observations by the rainfall or staff gage observer under a Stage I Condition,
and Stage II Condition, and a Stage III Condition; and a clear description of
an access route and means of travel during flood conditions to the [ dam
impounding structure ];
15. Evacuation procedures including notification, monitoring, evacuation, and reporting processes and responsibilities;
16. Evidence that the required copies of such plan have been submitted to the local organization for emergency management and the Virginia Department of Emergency Management; and
17. Certification of the plan by the owner.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part IV
Procedures
4VAC50-20-180. Inspections.
A. The director may make inspections during
construction, alteration or operation and maintenance as deemed necessary to
ensure that the impounding structure is being constructed, altered or operated
and maintained in compliance with the permit or certificate issued by the
board. The director shall provide the owner a copy of the findings of these
inspections. This The department's inspection does not relieve
the owner from the responsibility of providing adequate inspection during
construction, alteration, or operation and maintenance. During the
maintenance, construction, or alteration of any [ dam
impounding structure ] or reservoir, the director shall require the
owner to perform, at the owner's expense, such work or tests as necessary to
obtain information sufficient to enable the director to determine whether
conformity with the plans and specifications approved by the certificate is
being secured.
B. Periodic inspections during construction or alteration
shall be conducted under the supervision direction of a licensed
professional engineer who shall propose the frequency and nature of the
inspections subject to approval by the director provide for [ full-time ]
monitoring, review of contractor submittals, and appropriate confirmatory
testing of all facets of construction affecting the safety of the impounding
structure in accordance with the construction or alteration permit issued by
the board.
Periodic C. Required inspections during
operation and maintenance shall be conducted under the supervision of a licensed
professional engineer at an interval not greater than that required
to update the operation and maintenance certificate [ . ] At
a minimum, an annual owner's inspection shall be conducted when a professional
inspection is not required intervals designated under 4VAC50-20-105.
D. Every owner shall provide for an inspection by a licensed professional engineer after overtopping of the impounding structure or after flows cause damage to the emergency spillway. A copy of the findings of each inspection with the engineer's recommendations shall be filed with the board within a reasonable period of time not to exceed 30 days subsequent to completion of the inspection.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.1, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
[ 4VAC50-20-190. Right to informal fact-finding proceeding or hearing.
Any owner aggrieved by an action taken by the director or by the board without hearing, or by inaction of the director or the board, under the provisions of this chapter, may demand in writing an informal fact-finding proceeding pursuant to §2.2-4019 of the Code of Virginia or a formal hearing pursuant to §2.2-4020 of the Code of Virginia. A formal hearing may be granted only with the consent of the board ].
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.2, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-200. Enforcement.
Any owner refusing to obey any order of the board or the
director pursuant to this chapter may be compelled to obey and comply with such
provisions by injunction or other appropriate remedy obtained in a court proceeding.
Such proceeding shall be instituted by the board or in the case of an
emergency, by the director in the court which granted approval to the owner to
impound waters or, if such approval has not been granted, the proceeding shall
be instituted in any appropriate court. The provisions of this chapter
may be enforced by the board, the director, or both in any manner consistent
with the provisions of the Dam Safety Act (§10.1-604 et seq. of the Code of
Virginia).
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.3, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-210. Consulting boards committee.
A. When the board needs to satisfy questions of safety
regarding plans and specifications, construction, alteration, or
operation and maintenance, or when requested by the owner, the board may
appoint a consulting board committee to report to it with respect
to those questions of the impounding structure's safety of an
impounding structure. Such a board committee shall consist of
two or more consultants, none of whom have been associated with the impounding
structure.
B. The costs and expenses incurred by the consulting board
committee, if appointed at the request of an owner, shall be paid by the
owner.
C. The costs and expenses incurred by the consulting board
committee, if initiated by the board, shall be paid by the board.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.4, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-220. Unsafe conditions.
A. No owner shall have the right to maintain an unsafe
impounding structure which unreasonably threatens the life or property of
another person. The owner of any impounding structure found to have deficiencies
which could threaten life or property if uncorrected shall take the corrective
actions needed to remove such deficiencies within a reasonable period of time.
Designation of an impounding structure as unsafe shall be made in accordance
with §10.1-607.1 of the Code of Virginia.
B. Imminent danger.
1. If an owner or the owner's engineer has determined that circumstances are impacting the integrity of the impounding structure that could result in the imminent failure of the impounding structure, temporary repairs may be initiated prior to approval from the board. The owner shall notify the department within 24 hours of identifying the circumstances impacting the integrity of the impounding structure. Such emergency notification shall not relieve the owner of the need to obtain an alteration permit as soon as may be practicable, nor shall the owner take action beyond that necessary to address the emergency situation.
2. When the director finds that an impounding structure
is unsafe and constitutes an imminent danger to life or property, he shall
immediately notify the State Virginia Department of Emergency
Management and confer with the owner who shall activate the Emergency Action
Plan or Emergency Preparedness Plan if appropriate to do so. The owner of
an impounding structure found to constitute an imminent danger to life or
property shall take immediate corrective action to remove the imminent danger
as required by §10.1-608 of the Code of Virginia.
C. Nonimminent danger. The owner of an impounding structure
who has been issued a report by the board containing findings and
recommendations, by the board, for the correction of deficiencies which
that may threaten life or property if not corrected, shall undertake to
implement the recommendations for correction of deficiencies according to a
schedule of implementation contained in that report as required by §10.1-609 of
the Code of Virginia.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.5, eff. February 1, 1989; amended, Virginia Register Volume 18, Issue 14, eff. July 1, 2002; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-230. Complaints.
A. Upon receipt of a complaint alleging that the person or property of the complainant is endangered by the construction, alteration, maintenance or operation of an impounding structure, the director shall cause an inspection of the structure, unless the data, records and inspection reports on file with the board are found adequate to determine if the complaint is valid.
B. If the director finds that an unsafe condition exists, the director shall proceed under the provisions of §§10.1-608 and 10.1-609 of the Code of Virginia to render the extant condition safe.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §4.6, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part V
Design Requirements
4VAC50-20-240. Design of structures.
A. The owner shall complete all necessary investigations prior to submitting the design report (Design Report for the Construction or Alteration of Virginia Regulated Impounding Structures). The design report shall contain those components outlined in 4VAC50-20-70 for construction activities or those outlined in 4VAC50-20-80 for alteration activities. The scope and degree of precision required is a matter of engineering judgment based on the complexities of the site and the hazard potential classification of the proposed structure.
B. Surveys shall be made with sufficient accuracy to locate the proposed construction site and to define the total volume of storage in the impoundment. Locations of center lines and other horizontal and vertical controls shall be shown on a map of the site. The area downstream and upstream from the proposed impounding structure shall be investigated in order to delineate the areas and extent of potential damage in case of failure or backwater due to flooding.
C. The drainage area shall be determined. Present,
projected and potential future and planned land-use conditions shall
be considered in determining the runoff characteristics of the drainage area.
The most severe of these conditions shall be included in the design
calculations which shall be submitted as part of the design report.
D. The geotechnical engineering investigation shall consist of borings, test pits and other subsurface explorations necessary to adequately define the existing conditions. The investigations shall be performed so as to appropriately define the soil, rock and ground water conditions.
E. All construction materials shall be adequately researched
and selected so as to ensure that their properties meet as
constructed behavior will reasonably conform to design criteria. If on-site
materials are to be utilized, they shall be located and determined to be
adequate in quantity and quality.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.1, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-250. Design flood. (Repealed.)
The minimum design flood to be utilized in impounding
structure evaluation, design, construction, operation and maintenance shall be commensurate
with the size and hazard potential of the particular impounding structure as
determined in 4VAC50-20-50 and Table 1. Competent, experienced, professional
engineering judgment shall be used in applying those design and evaluation
procedures referenced in 4VAC50-20-320 of this chapter.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.2, eff. February 1, 1989; repealed, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-260. Emergency spillway Spillway design.
A. Every impounding structure shall have a spillway system with adequate capacity to discharge the design flood without endangering the safety of the impounding structure.
B. An emergency spillway shall be required.
CB. Vegetated earth or an unlined
emergency spillway may be approved when the applicant demonstrates that it will
pass the spillway design flood without jeopardizing the safety of the
impounding structure [ (such as by allowance of overtopping of a
structure not designed to permit overtopping) ]. In no case shall
[ dam impounding structure ] owners permit
the growth of trees and other woody vegetation in the emergency spillway area.
DC. Lined emergency spillways shall include
design criteria calculations, plans and specifications for open channel,
drop, ogee and chute suitable energy dissipators and for spillways
that include crest control structures, chutes, walls, panel
lining, sills, blocks, and miscellaneous details. All joints shall be
reasonably water-tight and placed on a foundation capable of sustaining applied
loads without undue deformation. Provision shall be made for handling leakage
from the channel or under seepage and uplift pressures from the
foundation which might adversely affect the structural integrity and structural
stability of the impounding structure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.3, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-270. Principal spillways and outlet works.
A. It will be assumed that principal spillways and regulating outlets provided for special functions will operate to normal design discharge capabilities during the spillway design flood, provided appropriate analyses show:
1. That control gates and structures are suitably designed to operate reliably under maximum heads for durations likely to be involved and risks of blockage by debris are minimal;
2. That access roads and passages to gate regulating controls would be safely passable by operating personnel under spillway design flood conditions; and
3. That there are no other substantial reasons for concluding
that outlets would not operate safely to fill full design
capacity during the spillway design flood.
B. If there are reasons to doubt that any of the above basic
requirements might not be adequately met under spillway design flood
conditions, the "dependable" discharge capabilities of regulating
outlets shall be assumed to be less than 100% of design capabilities capacities,
generally as outlined in the following subsections C through G of this section.
C. Any limitations in safe operating heads, maximum velocities to be permitted through structures or approach channels, or other design limitations shall be observed in establishing "dependable" discharge rating curves to be used in routing the spillway design flood hydrograph through the reservoir.
D. If intakes to regulating outlets are likely to be exposed
to dangerous significant quantities of floating drift debris,
sediment depositions or ice hazards prior to or during major floods, the
dependable discharge capability during the spillway design flood shall be
assumed to be zero.
E. If access roads or structural passages to operating towers
or controls are likely to be flooded or otherwise unusable during the spillway
design flood, the dependable discharge capability of regulating outlets will be
assumed to be zero for those period the periods of time during
which such conditions might exist.
F. Any deficiencies in discharge performance likely to result
from delays in the operation of gates before attendants could be reasonably
expected to reach the control for in must be taken into account when
estimating "dependable" discharge capabilities to be assumed assumptions
in routing the spillway design flood through reservoir the
impoundment. Reports on design studies shall indicate the allowances made
for possible delays in initiating gate operations. Normally, for projects
located in small basins, where critical spillway design flood inflows may occur
within several hours after intense precipitation, outflows through any
regulating outlets that must be opened after the flood begins shall be assumed
to be zero for an appropriate period of time subsequent to the beginning of
intense rainfall.
G. All gates, valves, conduits and concrete channel outlets shall be designed and constructed to prevent significant erosion or damage to the impounding structure or to the downstream outlet or channel.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.4, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-280. Drain requirements.
All new impounding structures regardless of their hazard
potential classification, shall include a device to permit draining of the
impoundment within a reasonable period of time as determined by the owner's licensed
professional engineer [ , subject to approval by the director ].
[ Existing drains on impounding structures shall be kept operational.
When practicable, existing impounding structures shall be retrofitted with
devices to permit draining. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.5, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-290. Life of the impounding structure.
Components of the impounding structure, the impoundment,
the outlet works, drain system and appurtenances shall be durable [ and
maintained ] or replaced in keeping with the design and planned
life of the impounding structure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.6, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-300. Additional design requirements.
A. Flood routings shall start at or above the elevation of the crest of the lowest ungated outlet. Freeboard determination and justification must be addressed by the owner's engineer.
B. All elements of the impounding structure and
impoundments shall conform to sound engineering practice. Safety factors,
design standards and design references that are used shall be included with the
design report.
C. Inspection devices may be required by the director for use by inspectors, owners or the director in conducting inspections in the interest of structural integrity during and after completion of construction and during the life of the impounding structure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.7, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-310. Plans and specifications.
The plans and specifications for a proposed impounding
structure required in 4VAC50-20-70 for construction activities and in
4VAC50-20-80 for alteration activities shall consist of a detailed engineering
design report that includes (Design Report for the Construction or
Alteration of Virginia Regulated Impounding Structures) and engineering
drawings and specifications, with the following as a minimum:
1. The name of the project; the name of the owner; classification of the impounding structure as set forth in this chapter; designated access to the project and the location with respect to highways, roads, streams and existing impounding structures and impoundments that would affect or be affected by the proposed impounding structure.
2. Cross-sections, plans, profiles, logs of test
borings, laboratory and in situ test data, drawings of principal and emergency
spillways, impounding structures, outlet works, drain system and
appurtenances, and other additional drawings project components
in sufficient detail to indicate clearly the extent and complexity of the work
to be performed.
3. Contract drawings should include, but not be limited to, foundation and abutment treatment, stream or river diversion, excavation and material fill processes, phased fill and compaction and drainage devices.
4. The erosion and sediment control plan, as approved by the local government, which minimizes soil erosion and sedimentation during all phases of construction or alteration.
3. The technical provisions 5. Technical
specifications, as may be required to describe the materials,
performance, and methods of the construction and construction quality
control for the project.
4. Special provisions, as may be required to describe
technical provisions needed to ensure that the impounding structure is
constructed according to the approved plans and specifications.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.8, eff. February 1, 1989; amended, Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-320. Acceptable design procedures and references.
To ensure consistency of approach, within the major engineering disciplines of hydrology, hydraulics, soils and foundations, structures, and general civil design, criteria and approaches from multiple sources shall not be mixed for developing the design of a given feature or facility without approval of the director. In all cases the owner's engineer shall identify the source of the criteria.
The following are acceptable as design procedures and references:
1. The design procedures, manuals and criteria used by the United States Army Corps of Engineers.
2. The design procedures, manuals and criteria used by the United States Department of Agriculture, Natural Resources Conservation Service.
3. The design procedures, manuals and criteria used by the United States Department of the Interior, Bureau of Reclamation.
4. The design procedures, manuals and criteria used by the United States Department of Commerce, National Weather Service.
5. The design procedures, manuals and criteria used by the
United States Federal [ Agency Energy ] Regulatory
Commission.
5.6. Other design procedures, manuals and
criteria that are accepted as current, sound engineering practices, as approved
by the director prior to the design of the impounding structure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from VR625-01-00 §5.9, eff. February 1, 1989; amended, Virginia Register Volume 18, Issue 14, eff. July 1, 2002; Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-330. Other applicable dam safety references.
[ A. ] Manuals, guidance, and criteria used by the Federal Emergency Management Agency, including the following:
1. Federal Guidelines for Dam Safety: Emergency Action Planning for Dam Owners, U.S. Department of Homeland Security, Federal Emergency Management Agency, October 1998, Reprinted January 2004; FEMA 64 or as revised.
2. Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow Design Floods for Dams, U.S. Department of Homeland Security, Federal Emergency Management Agency, October 1998, Reprinted April 2004; FEMA 94 or as revised.
[ B. Manuals, guidance, and forms provided by the department. Such materials may be located on the department's website at: http://www.dcr.virginia.gov. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
Part VI
Fees
4VAC50-20-340. Authority to establish fees.
Under §10.1-613.5 of the Code of Virginia, the board is
authorized to establish and collect application fees for the administration of
the dam safety program, administrative review, certifications, and the repair
and maintenance of [ dams impounding structures ].
The fees will be deposited into the Dam Safety, Flood Prevention and Protection
Assistance Fund.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-350. Fee submittal procedures.
A. [ (Upon the effective date of these
regulations,) Effective September 26, 2008, ] fees for
all application submittals required pursuant to 4VAC50-20-370 through 4VAC50-20-390
are due prior to issuance of a certificate or permit. No application for an
Operation and Maintenance Certificate or a Construction Permit will be acted
upon by the board without full payment of the required fee per §10.1-613.5 of
the Code of Virginia.
B. Fees shall be paid by check, draft or postal money order
payable to the Treasurer of Virginia, or submitted electronically (if
available), and must be in U.S. currency, except that agencies and institutions
of the Commonwealth of Virginia may submit Interagency Transfers for the amount
of the fee. All fees shall be sent to the following address (or submitted
electronically, if available): Virginia Department of Conservation and
Recreation, [ Dam Safety Receipts Control, P.O. Box 10150
Division of Finance, Accounts Payable, 203 Governor Street, 4th
Floor, ] Richmond, Virginia [ 23240 23219 ].
C. All fee payments shall be accompanied by the following information:
1. Applicant name, address and daytime phone number.
2. The name of the [ dam impounding
structure ], and the [ dam impounding
structure ] location.
3. The type of application or report submitted.
4. Whether the submittal is for a new permit or certificate issuance or permit or certificate reissuance.
5. The amount of fee submitted.
6. [ Dam Impounding structure ]
identification number, if applicable.
D. No permit fees remitted to the department shall be
subject to refund except as credits provided for in 4VAC50-20-390 [ D
C ].
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-360. Fee exemptions.
Impounding structures owned by Virginia Soil and Water
Conservation Districts shall be exempt from all fees associated with
[ Part VI this part ] in accordance with
§10.1-613.5 of the Code of Virginia. There will be no fee assessed [ for
a low hazard impounding structure exempted from fees pursuant to 4VAC50-20-51
or ] for the decommissioning of an impounding structure.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-370. Construction Permit application fees.
A. Any application form submitted pursuant to 4VAC50-20-70
for permitting a proposed impounding structure construction after [ the
effective date of these regulations September 26, 2008, ] shall
be accompanied by a payment as determined in subsection B of this section.
B. Fees shall be as follows:
1. $2,500 for High or Significant Hazard Potential impounding structures.
2. $1,000 for Low Hazard Potential impounding structures.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-380. Regular Operation and Maintenance Certificate application fees.
A. Any application for a six-year Regular Operation and
Maintenance Certificate after [ the effective date of these
regulations September 26, 2008 ] , except as otherwise exempted,
shall be accompanied by a payment as determined in subsection B of this
section.
B. Fees for High, Significant, or Low Hazard Potential impounding structures shall be as follows:
1. [ $1,500 $600] for High
Hazard Potential.
2. [ $1,000 $600 ] for
Significant Hazard Potential.
3. [ $600 $300 ] for
Low Hazard Potential.
[ C. Fees for extension of Regular Operation and Maintenance Certificates shall be $250 per year or portion thereof. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-390. Conditional Operation and Maintenance Certificate application fee.
A. Fees for [ issuance of ] a
Conditional Operation and Maintenance Certificate [ or for the
extension of a Conditional Operation and Maintenance Certificate for High or Significant
Hazard Potential impounding structures ] shall be as follows:
1. For a [ 2-year Certificate: $1,000
certificate for more than one year but no more than two years: $300. ]
2. For a [ 1.5-year Certificate: $750
certificate for one year or less: $150. ]
[ 3. For a 1-year Certificate: $500
4. For a 6-month Certificate: $250
B. Fees for a Conditional Operation and Maintenance
Certificate or for the extension of a Conditional Operation and Maintenance
Certificate for Low Hazard Potential impounding structures shall be as follows:
1. For a 2-year Certificate: $500
2. For a 1.5-year Certificate: $375
3. For a 1-year Certificate: $250
4. For a 6-month Certificate: $125
C. Fees for a Conditional Operation and Maintenance
Certificate or for the extension of a Conditional Operation and Maintenance
Certificate for any impounding structure that requires a modification in
spillway capacity due to changes in the regulations and that is eligible for a
delayed effective date pursuant to 4VAC50-20-125 shall be as follows:
1. For a 2-year Certificate: $200
2. For a 1.5-year Certificate: $150
3. For a 1-year Certificate: $100
4. For a 6-month Certificate: $50
B. The fee for an extension of a Conditional Operation and Maintenance Certificate shall be $250 per year or portion thereof. ]
[ D. C. ] The board may
allow a partial credit towards the Regular Operation and Maintenance
Certificate fee if the owner of the impounding structure has completed, to the
director's satisfaction, the conditions of the Conditional Certificate prior to
its expiration. [ Credits shall only be provided to the nearest
6-month interval. ]
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
4VAC50-20-400. Incremental Damage Analysis review fees.
[ The fee for the review of an incremental damage
analysis submitted pursuant to 4VAC50-20-52 shall be $225. Re-review of an analysis
determined to be incomplete or in error upon the department's prior review
shall cost an additional $45 per subsequent submittal. ] Should
the department determine that outside expertise to assist with the review
[ of an incremental damage analysis ] is necessary, the
applicant shall be responsible for the cost of such outside expertise. Such
costs shall be agreed upon in advance by the [ department and the ]
applicant.
Statutory Authority
§10.1-605 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 24, Issue 25, eff. September 26, 2008.
FORMS (Repealed.)
Dam Owner's Annual Inspection Form, DCR 199-098 (rev.
12/01).
Operation and Maintenance Application Class I, II and III
Impounding Structures, DCR 199-099 (rev. 12/01).
As-Built Report for Class I, II and III Impounding
Structures, DCR 199-100 (rev. 12/01).
Design Report for the Construction/Alteration of Impounding
Structures, DCR 199-101 (rev. 12/01).
Emergency Action Plan for Class I, Class II and Class III
Impounding Structures, DCR 199-103 (rev. 12/01).
Inventory Report for Class III and Class IV Impounding
Structures, DCR 199-104 (rev. 12/01).
Reinspection Report for Class I and II Impounding
Structures, DCR 199-105 (rev. 12/01).
Agricultural Certification for Impounding Structures, DCR
199-106 (rev. 12/01).
Transfer Application for Impounding Structures, DCR 199-107
(rev. 12/01).