Does a county commissioners court incur liability for failure to enforce its own subdivisions regulations?

Specifically, the regulations require a drainage survey to be done, however, the commissioners court have not required it to be done. Now we have citizens in a subdivision that is underwater.

Any thoughts?

No more so than does the Legislature incur liability for a failure to enforce state law. To me, that's the analogy that best frames the defensive position of the commissioners court. Their act of establishing the subdivision regulations is legislative (decision commited to their lawmaking authority, representing an edict of general applicability). They'll have individual legislative immunity, and a viable waiver of the county's sovereign immunity doesn't readily present itself. There's no real act of the court to predicate an inverse condemnation or nuisance suit upon, and the Tort Claims Act doesn't even come up on the screen (no tangible property used, discretionary exception, to name a couple of defensive matters). This discussion, however, presumes there's been no selective enforcement (we like group A, so we enforce in favor of them, but don't like group B, so we let their houses flood) from which federal constitutional claims may flow.

The problem, it seems to me, is more political. The questions of "why now" and "whose family member/buddy has been affected" are likely to surface if enforcement begins after a period of regulatory atrophy. Also, depending on your judiciary, if a declaratory claim is brought in the face of enforcement, a judge might lend a sympathetic ear to a claim that: there's been no enforcement in the past, so why should there be now?