A recent Hawai'i Supreme Court decision on the responsibility of local government to protect island coastal waters sets in motion an important new chapter in the environmental legacy of this state.

The key is how state and county governments will interpret this new obligation. It could become a tool for delay or obstruction of important economic development projects.

Or, as it should be, it should simply upgrade the vigilance of government authorities as they review and approve projects going forward.

The ruling implies that while state and county governments have for years had an obligation to review how a proposed project would affect coastal waters, that obligation has not always been fully met. Oddly enough, the court found that in the specific case before it, involving the controversial Hokuli'a development on the Big Island, neither the state nor the county violated its trust responsibilities for monitoring the project.

But beyond the facts of this particular case, the court made it clear that the state — and more critically, the counties — both have an "affirmative duty" to ensure that coastal waters are protected from harm caused by development.

This poses an additional burden on government that likely will translate into a call for additional resources and personnel.

But the upside will be that the state and counties can work more proactively with developers to ensure their projects do not harm coastal waters through runoff or other activities.

Anyone who remembers the massive degradation of Kane'ohe Bay by silting and runoff after a development boom in the early 1970s will recognize the importance of this matter. The bay is recovering, but it has taken decades.

The ruling was based on very straightforward language found in the Hawai'i Constitution: ". . .the state and its political subdivisions shall conserve and protect Hawai'i's natural beauty and all natural resources."

Simply put, this doesn't say "no" to development. It says "yes" to doing it right.