Very well put. Newly elected officials could be given a six month grace period to get any remediation efforts underway before their first tasting. Incumbents would not be eligible for a grace period.
One other point to add to rsync's comment:
One other point to mention is that rational choices cannot be made about things like pollution when measurement methods can be fudged and the health effects of specific pollutants are not necessarily well studied. Bottom line, putting it in one's own body is the best way to determine whether a sensible person would feel comfortable with the environmental exposure being forced upon citizens due to lax or imperfect regulation, or even imperfect science. Do I want to drink this discolored, foul smelling water just because it does not test positive for known carcinogens? Common sense is actually a surprisingly helpful guide here.
All that would happen is that regulations would begin to be enforced or modified to match the improved perception of reality informed by the tasting.
Think about it this way, climate change is a fairly abstract concept that is much easier to ignore than the fish dinner sitting in front of you that was caught in water your administration declared safe.