Homeowners never know anything about sewage systems until after their systems fail.  Often, the homeowner is left holding the bag of problems after designers and installers have moved on to bigger and better projects.  The people who designed and installed the systems cannot be compelled to return to the failed system.  

I would ask the board to consider making designers, installers, and operators provide a bond or warranty to back up their work should a problem develop.  If the board can't or won't require a bond or warranty, then I would suggest that a regulation be adopted to say that a licensee must respond within 3 days of notice that a sewage system, for which he designed, installed, or operated, is malfunctioning. 

Owners can't pursue a claim against the designer or installer because they didn't hire these people to do the work.  If the board required licensees to bond, warranty, or respond to owners with failed systems, then homeowners would be better protected if a problem occurred.  The issue would not be about a licensee doing bad work, the issue would be how to collect from the insurance, bonding, or warranty program and whether the licensee responded to the problem.