The federal Safe Drinking Water Act sets standards for drinking water quality in the United States.

Launched in 1974 and administered by the U.S. Environmental Protection Agency, the Safe Drinking Water Act oversees states, communities, and water suppliers who implement the drinking water standards at the local level.

The act’s regulations apply to every public water system in the United States but do not include private wells serving less than 25 people.

According to the EPA, there are more than 160,000 public water systems in the United States.

The Los Angeles River is gradually being transformed from a giant, trash-strewn stormwater channel to a recreational and open space corridor that continues to provide flood control.

Deadly floods in the 1930s led the U.S. Army Corps of Engineers to straighten and pave nearly all 52 miles of the river channel in concrete. The trough was designed to keep flood water from destroying property, to manage the discharges from sewage treatment plants and to flush stormwater to the Pacific Ocean.

Since the 1990s, a grassroots campaign to restore some of the natural character of the river has gained political traction.

Los Angeles has the lowest ratio of open space per capita of any major American city, due to rapid growth and poor urban planning.

A bill passed by the state Legislature in 1992 established a Los Angeles River Conservancy to develop comprehensive planning strategies along the concrete corridor.

Additionally, a citizens’ group, Friends of the Los Angeles River, has helped coordinate the cleanup and rejuvenation of the river.

In the past, river advocates considered painting the river channel blue to give it a more natural look.

In 2010, the U.S. EPA deemed the river navigable and subject to the protections of the Clean Water Act. A year later, the Army Corps permitted kayaking along soft-bottom stretches north of downtown.

In 2014, the Army Corps recommended approval of Los Angeles County’s plan to restore habitat, widen the river, create wetlands, and invite new commercial and residential development. The county Board of Supervisors approved the Los Angeles River Master Plan in 2022.

In the winter of 2024, the river captured near-record precipitation from a series of intense atmospheric rivers, thanks to drain clearing and dredging of debris, Army Corps officials said.​

Los Angeles River supporters are looking beyond the river’s banks toward improved management of the Los Angeles River watershed as a whole. Advocates seek a strategy that integrates and coordinates the management of water quality, flood control and habitat restoration across jurisdictional boundaries.

The federal government passed the Endangered Species Act in 1973, following earlier legislation. The first, the  Endangered Species Preservation Act of 1966, authorized land acquisition to conserve select species. The Endangered Species Conservation Act of 1969 then expanded on the 1966 act, and authorized “the compilation of a list of animals “threatened with worldwide extinction” and prohibits their importation without a permit.”

Climate change involves natural and man-made changes to weather patterns that occur over millions of years or over multiple decades.

In the past 150 years, human industrial activity has accelerated the rate of change in the climate due to the increase in greenhouse gases (carbon dioxide, methane and nitrous oxide, among others). Scientific studies describing this climate change continue to be produced and its expected impacts continue to be assessed.

The California Aqueduct, a critical part of the State Water Project, carries water from the Sacramento-San Joaquin Delta to the San Joaquin Valley and Southern California.

Established as part of a $1.75 billion bond passed by voters in 1960, the 444-mile-long California Aqueduct (formally known as the Edmund G. Brown California Aqueduct) begins at the Harvey O. Banks Pumping Plant in the Delta. It parallels Interstate 5 south to the Tehachapi Mountains.