Waterman Bubby Powely crabs in the early-morning hours on the Chesapeake Bay near Hooper Island, Md., in June. (Linda Davidson/The Washington Post)

J. Charles Fox and Jeff Corbin served as senior advisers at the Environmental Protection Agency, where they advised the EPA administrator on Chesapeake Bay issues. Previously, they held senior positions in the Maryland and Virginia governments and worked for nonprofit organizations on the Chesapeake for more than 40 years combined.

In the spring, scientists announced that the Chesapeake Bay was improving, with most health indicators trending in the right direction. Pollution was decreasing, fish and wildlife populations were increasing and underwater grasses were thriving in places. And it may come as a surprise that the secret to the bay’s recent improvement was not a technical or scientific “silver bullet” but leadership from a former Virginia governor.

It’s not yet time to celebrate, of course. Chesapeake Bay challenges remain monumental, particularly because of agriculture pollution in Pennsylvania and on Maryland’s Eastern Shore and contaminated stormwater runoff throughout our highly developed, 64,000-square-mile watershed. But it’s time to reflect on our progress and what got us here. The bay’s improving health is not a supernatural miracle; it is a product of decades of difficult political decisions by the region’s elected officials. And make no mistake, the Chesapeake is being viewed as a litmus test for other great waters around the nation that are in dire need of restoration.

Having served in many different roles on Chesapeake restoration efforts, we’ve both seen policies that work, as well as ones that never lived up to their promises. The most important lesson we’ve learned?

Leadership matters.

Particularly from the federal government. Indeed, the policies that flow from this fall’s elections will seal the fate of the Chesapeake for years to come. With past commitments left unfulfilled, and a widely supported 2025 restoration deadline looming, will its health continue to improve as we meet our cleanup goals on schedule? Or will the bay be bogged down by bureaucracy or mired in conflict?

The modern Chesapeake cleanup effort was born in 1983, a product of a federal-state collaboration, with leadership from a U.S. senator, the administrator of the Environmental Protection Agency and the governor of Maryland. With the support of the region’s governors, state legislators and the D.C. mayor, the effort evolved over the years into a true partnership.

Yet the federal government is a partner without equals. It represents the broader interests of the region, not those of a particular jurisdiction. It has a core responsibility of implementing federal environmental laws, upon which many state and local laws are built. It is the glue that binds the bay cleanup program together.

There have been a handful of truly major changes in policy over the past 35 years. The 1987 Chesapeake Bay Agreement, for example, took the unprecedented step of establishing and adopting numeric goals and deadlines to reduce pollution and restore the bay ecosystem.

Another significant policy change occurred about seven years ago. Few elected officials understood how to leverage the power of the federal government in the same manner as Tim Kaine, then Virginia’s governor and now the Democratic nominee for vice president. Just months after taking office, President Obama issued a first-ever executive order for the Chesapeake, outlining his expectations for accelerating action. Kaine was instrumental in making that happen, demonstrating that there is real value in a federal-state partnership.

The inclusion of accountability, including short-term objectives, was the result of Kaine’s leadership during his term as chairman of the Chesapeake Executive Council — the top body that oversees the Chesapeake restoration efforts.

Did this new pollution control regime save the bay? Of course not. Full restoration of the Chesapeake is a long-term struggle that must be embraced by our future leaders.

Federal intervention in delivering clean water and healthy ecosystems is sometimes misunderstood or, in some cases, viewed with hostility by state and local governments. Intergovernmental relationships are delicate and need to be managed respectfully. However, the citizens of Flint, Mich., because of the water crisis there, understand why we need federal leadership. Those of us who know and care about the Chesapeake do as well.

Given the significant economic and social value of a healthy Chesapeake Bay, it is paramount that issues defining the Chesapeake’s future receive attention from candidates running for federal office. Lessons from leaders such as Kaine have demonstrated how governments can work together to make progress. This year’s elections, and the new leaders who will emerge, will be profoundly important to the health of the Chesapeake Bay and the communities in this region.