Congressional leaders will gather this weekend in Minneapolis for hearings on the future of wetlands in America. Much hinges on their ability to generate momentum toward lasting legal protections for these incomparable resources.

We have lost more than half of our country's natural wetlands and continue to lose them at a rate of 80,000 acres per year. What's worse, the fabric of our current wetlands protection laws has been worn threadbare.

The passage of the Clean Water Act in 1972, with a provision known as Section 404 that protected wetlands, represented a seminal moment in American conservation history. Section 404 included unprecedented language that allowed us to slow down nationwide draining and filling of wetlands.

More than 30 years later, in the wake of bad decisions by the U.S. Supreme Court, we find this protection weakened by challenges focusing on certain words in Section 404, namely "navigable," as in, these protections extend to the navigable waters of the United States.

The Supreme Court's most recent decisions came in cases that dealt with whether developers can build on wetlands adjacent to tributaries that flow into larger water bodies. Not navigable in the traditional sense of the word, these wetlands are nevertheless of huge importance.

The court's ruling was a three-way-split decision that has made an already confusing regulatory arena even more confusing.

But there's one bit of certainty to be gleaned from this latest scrutiny of the Clean Water Act's wetlands protections: We need decisive new legal wording so all Americans know exactly what constitutes a wetland in need of protection. We need language that prevents wetlands protection questions from being continually kicked into our courts.

Wetlands provide crucial habitat. Almost half of our country's bird species nest or feed in wetlands. One-third of our plant species live in wetlands. More than one-third of our threatened and endangered species live only in wetlands. Coastal wetlands provide habitat, especially as nurseries, for more than 75 percent of fish and shellfish caught commercially and up to 90 percent of fish caught recreationally.

Wetlands give us cleaner water. When water moves into a wetland, it slows down and pollutants settle to the bottom. A wetland and its plants filter out and absorb much of the water's pollutant load before passing it into our streams, rivers, lakes and estuaries.

Wetlands prevent floods. As water levels rise, wetlands accommodate the rising water, spread and store the influx, and reduce the velocity of downstream flows.

Before the recent cases came to the Supreme Court, the United States was already in need of more effective wetlands protection. Any hopes that the cases would deliver clear new national guidance on how to properly stem wetlands loss have been dashed.

It is time to put binding new language in place that draws bright shining lines around a national resource more in need of protection than ever. In the coming congressional hearings, our leaders have a chance to start doing exactly that.

Mullins is the wetlands and farm policy initiative manager for the Theodore Roosevelt Conservation Partnership. He is helping organize this weekend's summit.