President Donald Trump’s plan to strip the Environmental Protection Agency of funds aimed at restoring the Chesapeake Bay is a reminder of just how long that effort has been underway — and how often it has run afoul of perceived economic interests.

Back in 1973, the Virginia Department of Transportation —then known as the Highway Department — was wrapping up construction of the Smithfield Bypass and was preparing to construct the new Church Street Cypress Creek Bridge.

Just a couple of years earlier, the state had designed the Smithfield Bypass bridges and chose, without opposition, to dig canals through the marshlands that those bridges cross to enable pile drivers to be floated in place.

Such canals not only destroy the marsh under the bridge being built but affect adjacent marshlands, particularly in deep mud environments like the Pagan River and Cypress Creek. Surrounding mud slips into the canals, changing the ecology some distance from the actual dredged area.

By the time the state designed the Church Street Bridge across the Cypress, impacts on marshlands were being looked at more closely and less intrusive methods were being recommended.

The Virginia Institute of Marine Science and the U.S. Department of the Interior opposed the project because of the Highway Department’s plan to dredge a canal through the marsh on the east side of the Cypress.

The Coast Guard denied a permit for the bridge in March 1973 based on those objections.

Local officials went ballistic. The drawbridge then crossing the creek was old, narrow and in need of replacement.

In a blistering resolution sent to every politician from Richmond to Washington who might influence the matter, the Smithfield Town Council declared that the town was “cognizant of the aim of ecology and preservation of natural resources” but that preserving natural resources “at excessive cost to the taxpayer is not the intent of laws with regard to preservation.”

Isle of Wight joined the protest. In a letter, the Board of Supervisors said not building the bridge “will do untold violence to the economic life support system of the whole area.”

The town won. Within a month, the Coast Guard had run up a white flag and issued the permit and the bridge was built.

It is possible to drive pilings across marsh without destroying the marsh, but doing so, at least back then, was more expensive than just dredging a canal to accommodate a pile driver. That was the essence of the issue.

The Cypress Creek marsh was determined to have the last laugh, however. The Highway Department decided to pour fill dirt into the last few yards of the marshland and the fill kept sinking into the underlying mud. The just-dug canal filled back in and had to be partially re-dredged before the bridge could be constructed.

The Cypress Creek Bridge was needed, though it probably could have been built without destroying acres of marshland, but the dustup over dredging the marsh proved how quickly local government officials can abandon any pretext of environmental concern to protect what they perceive as more important economic interests.

It was a telling example of why environmental rules, for the most part, have to be set at the state and national level. Town councils and boards of supervisors are simply not able to make the politically tough choices that environmental protection often requires.

We may also learn in the coming years whether states are able to protect the environment after the EPA is dismantled.