We agree with almost all of what the backers of Measure C say.

It is time to take a hard look at the current regulations protecting the streams and trees in the hills surrounding the valley. Those forests and streams feed the Napa River and recharge the reservoirs and aquifers that supply the cities and vineyards on the Valley floor. Those trees are not just scenic treasures, but also a line of defense against the looming menace of climate change.

Just as we did not wait for the start of urban sprawl before enacting the Ag Preserve in 1968, so too we should not wait until there is a tree-clearing gold rush in our back country, or until our aquifers begin to fail, before protecting the national treasure that is Napa County.

Where we do disagree with the backers of Measure C is in the notion that we have exhausted all possible avenues to protect the watersheds before reaching for the dangerously blunt and inflexible weapon of a ballot measure.

It is a rare piece of legislation that does not turn out to have loose ends, regulatory hiccups and unintended consequences that need to be cleared up later.

Legislators are constantly fine tuning laws to make them work better in practice.

Make no mistake: Measure C is an enormously complicated and consequential piece of legislation and it is absolutely sure to have many wrinkles and consequences that need to be field tested in order to see if they work properly.

Yet this measure was drafted without any of the usual steps that a major piece of legislation undergoes: hearings, public input, and expert vetting, from both outside specialists and staff that would be responsible for interpreting and enforcing the law. Even a minor tweak to Measure C would require a whole new ballot initiative in some future election.

We believe it is premature to take such a draconian and risky step.

This legislation is, therefore, the right idea in the wrong vehicle. On this basis alone, we urge voters to reject Measure C.

At the same time, we urge the Board of Supervisors to see Measure C for what it is: A legitimate cry of frustration by many county residents who fear that their leaders are not acting to protect their way of life and their environment.

The board should therefore take robust and unmistakable action to examine the rules governing development on our hillsides. There is already a promising move in that direction, with a joint study by the county and the city of Napa to examine development in the watershed that feeds the Milliken reservoir. The board should expand that to examine the entire county above the Valley floor to make sure we are protecting our resources in a forward-looking way.

If, in two years, we have not seen unmistakable signs of action from the supervisors, the editorial board may very well join Measure C’s current backers in supporting more drastic action by the voters.