Every one of us has the basic, human right to clean, drinkable water. Our health, our communities, and our economy depend on it.

That’s why we must speak out about the Trump administration’s recent proposal to roll back key clean water protections mandated by the Waters of the United States rule. The proposal seeks to remove federal pollution controls from wetlands and smaller streams that don’t immediately drain into larger waterways. The ostensible intent of the rollback is to allow landowners and businesses more control in how they manage their land. ​

Unfortunately this action is shortsighted, and it threatens the clean water that entire communities and economies depend on. If the proposal goes through, critical streams and wetlands will be vulnerable to contamination and may even be paved over. This will jeopardize the progress we have made throughout the Delaware River system—including parts of Pennsylvania, New Jersey, New York, and Delaware — on the health of the creeks, lakes, and rivers where we fish, swim, and kayak, and from which our drinking water flows.

Nearly half a century ago, our nation’s leaders established the Clean Water Act to better protect water resources for the American people. That was — and remains — a shining accomplishment in our nation’s history. After decades of reckless pollution, these protections successfully helped our rivers, streams, and wetlands slowly recuperate. A smart, science-based movement arose to protect clean water, and to prevent more pollution by creating protections for streams and rivers both small and large. These protections also make good economic sense: While we might see limited financial benefits from paving over wetlands, they would come with the much greater costs of having to purify our drinking water after these delicate acres — which serve as nature’s filters — are destroyed.

In our region, dozens of nonprofit organizations, scientists, and local government champions have aligned their work to protect clean water. The Clean Water Act is the foundation of this local and regional work — it provides the common sense standards we rely on to keep our waters drinkable, swimmable, and fishable.

In and around Philadelphia, our drinking water comes from the Delaware River system, which is the lifeblood of the Mid-Atlantic, providing drinking water to over 15 million Americans within four states. The river system includes 700,000 acres of wetlands and roughly 25,000 miles of rivers and streams. In the past few decades, we’ve already lost too many acres of precious wetlands to development. With this rollback, as much as a third of the remaining wetlands would lose protection. We simply can’t afford to lose more of these essential natural filters.

While many streams will remain protected, seasonal streams and wetlands will not. The vital, small wetlands and streams in the upper reaches of our river system are most vulnerable, and would be most affected by this proposal. History has shown that they are easy to destroy — and hard to bring back. All water flows downstream, and pollution in these places has major impacts for those communities and elsewhere, including contamination of our drinking water and devastating flooding.

The federal government’s recent announcement moves us away from those protections that keep dangerous and expensive pollution out of the rivers and streams that supply our drinking water. While our commitment to safeguarding clean water remains strong, the setbacks to clean water that this rollback will create are simply more than local governments and the nonprofit sector can overcome.

The Clean Water Act should be defended in the original spirit in which it was created: to protect the integrity of our waterways for the benefit of the people and natural communities that rely on clean water.

Andrew Johnson is the Watershed Protection Program Director at the William Penn Foundation, Carol Collier is the Senior Advisor for Watershed Management and Policy at the Academy of Natural Sciences at Drexel University, and Peter Howell is Executive Vice President at the Open Space Institute.