Growing up in the 1970s, I took for granted the trash piles along the highway, tires washed up on beaches and smog fouling city air.

Such scenes are why the first Earth Day — on April 22, 1970 — energized the nation. In the largest single-day public demonstration in U.S. history, roughly 10% of the population took to the streets to shout together: “Enough is enough!”

Republican and Democratic politicians alike listened. Over the decade that followed, all the nation’s foundational environmental laws were passed with strong bipartisan support, including the Clean Air Act, Clean Water Act and Endangered Species Act.

These laws are taking a beating at the moment, including from the Environmental Protection Agency — the federal agency created in 1970 to protect the environment. The agency’s leader, Lee Zeldin, boasted of “driving a dagger straight into the heart” of environmental regulations. President Trump regularly derides environmental laws as job killers and government overreach.

The conditions that made these laws necessary have largely been forgotten, allowing critics to focus entirely on costs while ignoring the laws’ very real benefits and achievements.

That’s why I was excited to learn recently about the Documerica project: 20,000 photos taken from 1972 through 1978 that show in clear visual evidence how dirty the U.S. used to be. Looking back at it now should wake people up to how much better the environment is today.

Environmental protection was a bipartisan effort in the 1970s: The EPA was created by President Nixon, a Republican. The agency’s first leader was William Ruckelshaus, a Republican congressman from Indiana.

Inspired by the famous photographs of Depression-era farmworkers commissioned in the 1930s by the Farm Security Administration, Ruckelshaus’ EPA commissioned a nationwide photo record. The goal was to create a “visual baseline” that would demonstrate the agency’s future progress.

To say America’s landscape was littered in the 1970s is not merely poetic phrasing. Waste disposal was a matter of local law, and illegal dumping was commonplace. Drums of pesticides and chemicals could be sent to the local dump along with tires and just about anything else people and companies wanted to get rid of. When the dump was full, it was covered with topsoil and became open land, ready for recreation or building construction.

One place where this happened was Love Canal, a neighborhood near Niagara Falls, N.Y. A dump holding decades of chemical drums from the Hooker Chemical Co. was lightly covered and sold to the town for $1. A neighborhood was built on the land.

Only when people noticed high levels of miscarriages and cancer clusters among the residents — and saw waste oozing in through basement walls — did opinion change.

In 1976, Congress passed the Resource Conservation Recovery Act to track waste materials from their creation to their disposal and set tough standards for how to dispose of them. But by then, decades of unregulated waste disposal had contaminated sites all over the country. The contaminants, toxicity and people responsible were often unknown.

Four years later, the 1980 law known as “Superfund” set standards and assigned financial responsibility for cleaning up hazardous waste sites. The law created a multibillion-dollar fund that could pay for the cleanups and required potentially responsible parties to reimburse the government or clean up the sites on their own.

Suddenly, companies paid much more careful attention to their waste disposal.

Just as with dumps on land, all kinds of waste used to be disposed of in rivers, lakes and harbors. There was a federal law in place, but it was ineffective and relied on states to set limits and enforce them.

I had the misfortune in 1978 to capsize while sailing on the Charles River in Boston. My shame turned to a dermatologist’s visit when I broke out in rashes the next day. You fell in the Charles at your peril.

Environmental advocates weren’t kidding when, in the 1960s and 1970s, they declared “Lake Erie is a dead lake” because of all the industrial pollution pouring into its waters. An oil slick on Cleveland’s Cuyahoga River famously caught fire in 1969 — actually the 12th time the river had burned in a century.

The Clean Water Act of 1972 sought to create a national standard, requiring companies that wanted to discharge waste into waterways to get a federal permit and use the best available technology to reduce the amount and toxicity of what they did dump. The act also provided billions of taxpayer dollars to upgrade sewage treatment plants, so they didn’t just dump untreated sewage into the water.

The ambitious goal was to end water pollution entirely and make all of the nation’s waters safe for swimming and fishing within a decade. Those aspirational goals for the country’s waters still have not been fully met, though Ruckelshaus used to quip that at least they are not flammable. And by now, the Charles River and other urban waterways that people avoided in the 1970s boast all manner of recreation, with little or no risk of rashes even while swimming.

Perhaps the most obvious improvement since the 1970s has been in air quality around the U.S.

The horrible smog around Los Angeles is well known. But many other cities were blanketed in polluted air that led to respiratory illnesses and millions of early deaths across the nation over the decades. In Pittsburgh it was only half-jokingly said that you had to floss your teeth after breathing.

The Clean Air Act of 1970 was the first law to require the EPA to set uniform nationwide standards for air quality. In short order, lead was phased out of gasoline, catalytic converters were required on cars, acid rain was ended and the sources of smog were stringently regulated. An EPA study found that the benefits under the law exceeded costs by a factor of more than 30 to 1 and, in 2020 alone, prevented more than 230,000 early deaths.

I could go on with photos and stories about laws from the 1970s that changed how Americans treat our lands and waters. But it all boils down to two simple facts. First, with the exception of greenhouse gases, which have been in effect unregulated, every major measure of environmental health has improved significantly over the last five decades. And second, those improvements all occurred during times of strong economic growth, with inflation-adjusted gross domestic product increasing fivefold.

Calling these laws “job killers” misses the point entirely. They created jobs and stopped environmental killers. Regulations have their costs, to be sure, but the Documerica photographs show just how far the nation has come, and what is at risk if we forget.

James Salzman is a professor of environmental law at UC Santa Barbara School of Environment and UCLA Law School. This article was produced in collaboration with the Conversation.