Sewer systems throughout the country are spilling enough raw sewage and waste into oceans and streams to fill more than 1 million Olympic-sized swimming pools every year, according to a federal report released Thursday.
Despite three decades of costly improvements driven by the Clean Water Act, the Environmental Protection Agency concluded that outdated and poorly maintained sewer systems still posed a serious public health threat.
In its report to Congress, the EPA said that sewer overflows were commonplace and responsible for sickening thousands of swimmers every year. Sewage contains an array of bacteria, viruses and parasites capable of causing human illnesses, as well as pollutants that harm fish and other wildlife.
The EPA said further sewage control was "vital to reducing risks to public health and protection of the environment." The agency recommended improved maintenance of the nation's sewer systems, many of which need to be overhauled.
The report came on a day when L.A.'s popular Dockweiler State Beach was closed after 200 gallons of sewage spilled from the city's Hyperion treatment plant. After decades of such spills, Los Angeles agreed this month to replace several hundred miles of old pipes and improve its maintenance to settle a lawsuit filed by the EPA, state officials and environmentalists.
Every year, 850 billion gallons of untreated sewage and waste spill from combined sewer systems, which mix sewage with storm-water runoff, according to the report.
These systems, most of which were built in the late 19th and early 20th centuries, are located in 32 states, mostly in the Northeast and around the Great Lakes. They were designed to spill waste into waterways, mostly rivers and streams, when the sewage and storm-water combination exceeded the system's capacity.
Another 3 billion to 10 billion gallons of raw sewage flow from the more modern systems, such as those in Southern California, that do not handle storm water.
There are about 23,000 to 75,000 spills each year in these systems, mostly small ones of less than 10,000 gallons, the EPA report says. Blockages and breaks in sewer lines cause most of the overflows. However, when it comes to volume spilled, rainy weather was responsible for the worst accidents. Rainwater seeps into aging, faulty sewer lines.
In Southern California, waste that spills from sewer lines often winds up on residential streets and eventually flows into the ocean.
