Californians strongly support action by state and federal agencies to ensure that the water in our streams and the water we drink are free of dangerous contaminants, and that our precious wetlands are preserved. Unfortunately, the Trump administration and Congress propose to weaken federal Clean Water Act protections for those essential resources.

But California regulatory agencies needn’t and shouldn’t wait for this federal rollback. They should instead take action proactively to use state law to ensure clean water and wetlands protections for all Californians.

The target of this rollback is a long-contested rule called the Clean Water Rule, also known as the “Waters of the U.S.” rule. The rule was adopted by the Obama administration in 2015, an overdue response to a pair of Supreme Court rulings in 2001 and 2006 that created a great deal of uncertainty about just what waters the Clean Water Act actually protects.

The Clean Water Rule is critical, as it specifies what waters are protected by the federal Clean Water Act. If federal agencies find that a particular wetland or stream is covered by the law, then stringent federal protections kick in to ensure that streams and wetlands remain clean, that fish and wildlife are protected and that our drinking water supplies aren’t tainted. But if federal agencies find that a particular wetland or stream isn’t protected under the Clean Water Act, then those federal protections don’t apply.

For California, there’s a great deal at stake. In the water-rich eastern U.S., defining a wetland or a stream is relatively easy. Where the rains fall year-round, wetlands are almost always wet. That’s not true in California, where our Mediterranean climate means that some of our wetlands and streams regularly go half a year or more without rainfall.

California’s seasonal streams and wetlands, however, are still critically important. For example, that seasonal rainfall pattern is one reason why millions of waterbirds migrate north from Central Valley and Bay Area wetlands. Over millennia, these and many other species have adapted to the seasonal nature of our wetlands.

Additionally, if industrial operations are allowed to dump into wetlands and streams that may be dry for the summer months, then contaminants will simply flow downstream when the rains return.

Finally, filling seasonal wetlands means more than contaminated water supplies and lost wildlife habitat. California wetlands absorb flood waters during extreme rain and coastal flooding events. We need look no farther than Houston to see the folly of developing our wetlands. Federal Clean Water Act requirements that encourage development elsewhere can help protect lives by keeping development out of flood-prone wetlands.

If the federal Clean Water Rule rollback isn’t stopped, the wildlife, water supply and flood-control benefits from thousands of acres of California wetlands and thousands of miles of California streams could be in jeopardy.

Fortunately, California has a strong set of tools to step in and protect wetlands and streams. The California legislature passed the Porter-Cologne Act in 1969, giving the State Water Resources Control Board broad authority to protect the “waters of the state.” No less important, the current State Water Resources Control Board, with members appointed by Gov. Jerry Brown, is the most far-sighted and competent board in four decades. Our state laws and agencies must respond to the federal challenge and act in the face of pending federal Clean Water Act rollbacks.

As a first step, the state should adopt its own wetlands definition and more clearly develop protections under state law. The board recently released a draft wetland policy that it plans to finalize before the end of the year. It’s a reasonable draft that can and should be strengthened. For example, the board should clarify that all applicants will be required to study alternatives to ensure that they avoid filling existing wetlands whenever possible.

The board should also clearly state that developers who fill wetlands will be required to restore at least one acre of habitat for each acre lost. After all, California has already lost more than 90 percent of our wetlands – which led former Gov. Pete Wilson to adopt a “no-net-loss” of wetlands policy in 1993. Clearly, two key steps to achieving this policy are ensuring that we avoid filling wetlands wherever we can and that wetlands that are filled are fully offset.

The board has been working on this “wetland policy” for over a decade, in response to the same Supreme Court rulings that led to the federal Clean Water Rule. However, now that federal protections are threatened, the board should feel a new urgency to act.

California has the ability to respond promptly to the looming threats to the federal clean water program. The Golden State has strong environmental protection laws and strong institutions charged with implementing them. The debate over protections for wetlands and streams is an important milestone. The State Water Board’s overdue efforts to adopt a strong wetlands policy will be among the first tests of California’s ability to stand up to the grave assault on the environment and public health taking place in our nation’s capital.

The views expressed in this article belong to the author and do not necessarily reflect the editorial policy of Water Deeply.