Water Pollution

The ocean provides so much for us – food, medicine and much of the oxygen we breathe. Today, the ocean is facing grave threats from pollutants that enter the ocean and not only harm marine life but also directly impact humans.

Take Action Against Water Pollution

Stewardship of the ocean begins at home.
You have the power to turn the tide and take everyday actions that will help prevent pollutants and trash from reaching our global ocean.

  • Keep trash and chemicals out of storm drains, including pet waste. Storm water flows into the sea, carrying pollutants which can lead to beach closures.
  • Plant a native or drought-tolerant plant garden. Native and drought-tolerant plants can help you reduce the use of water and fertilizers.
  • Plant an organic garden. Some chemical fertilizers and pesticides from lawns and gardens can wash into the ocean and contribute to water quality issues.
  • Make your own mulch by composting and use organic fertilizers only when needed.
  • Recycle used motor oil. Don’t let motor oil spill on the ground because rain will wash it into the storm water drains, and from there out to the ocean, where it can harm or kill marine life. Find an oil-recycling center near you.
  • Dispose of household cleaners properly. Household cleaning products, paint, pesticides, fluorescent light bulbs, and batteries pose a threat to water quality. Find more information about free collection centers.
  • Check the labels of the personal care products, such as face and body wash, toothpaste and more, and stop using products containing polyethylene or polypropylene microbeads. #BanTheBead

Click here for more everyday actions!

Find out more about what water pollution is and the top 10 ways you can reduce water pollution from your home.

Where Does Pollution Come From?

Point Source Pollution

Pollution can come from point sources, or single identifiable sources, such as factories or wastewater treatment facilities. Factories, oil refineries and electronic manufacturers typically release one or more pollutants into water they discharge (called effluents). Some factories discharge their effluents directly into a water body. Others treat it themselves before it is released, and still others send waste to sewage treatment plants for handling. Sewage treatment plants treat human wastes and send the treated effluent to a stream or river and ultimately to the ocean.

Visit the U.S. Environmental Protection Agency’s (EPA) EnviroFacts Web site to find facilities near your home with permits to discharge wastewater. EPA’s EnviroMapper is an interactive map showing the locations of these facilities. In California, the State and Regional Water Resources Control Boards (State Water Boards) regulate the effluents discharged directly into water bodies (streams, rivers, lakes, reservoirs, and the ocean). For more information about water quality monitoring data and assessment information go to My Water Quality.

Polluted Runoff

Image Credit: NOAA Ocean Explorer

Image Credit: NOAA Ocean Explorer

Polluted runoff (also known as nonpoint source pollution) comprises the majority of pollution in the ocean off California. When it rains or when you water your lawn or you wash your car, water picks up pollutants and carries them into our storm drains. Unlike the sewer system, most cities do not have treatment plants, or even filters, for this runoff. As a result, the pollutants found on streets, parking lots, buildings, yards and golf courses ultimately enter creeks and rivers, and eventually flow into the ocean. The kinds of pollutants found in runoff include motor oil, trash, pet waste, fertilizers, pesticides and dirt. These pollutants harm marine life, endanger human health and lead to costly beach closures.

The four categories of polluted runoff or nonpoint source pollution that enter the coastal ocean are domestic, industrial, agricultural and marine.



Oil spills can cause enormous damage to the marine environment and species, human health, coastal tourism, the fishing industry and recreational opportunities. For example, the April 2010 Deepwater Horizon oil spill was the largest accidental marine oil spill in the history of the petroleum industry, releasing over 4.9 million barrels of oil. The spill area affected 8,332 species, including more than 1,200 fish, 200 birds, 1,400 mollusks, 1,500 crustaceans, four sea turtles and 29 marine mammals. Despite the impacts of oil spills, they are responsible for only approximately 12 percent of the oil entering the ocean each year. According to a 2003 report by the U.S. National Research Council, seventy percent of oil entering the ocean from humans results from consumer uses, largely runoff related to the transportation sector.

Contaminants of Emerging Concern (CECs)

Contaminants of Emerging Concern are a diverse group of chemicals that enter the marine environment through both point and nonpoint sources. These contaminants are used industrially, as well as for pesticides, pharmaceuticals, personal care products and food additives. These contaminants are of emerging concern because they are commonly found in the marine environment and have possible negative environmental and biological implications, yet most have no current regulation for their uses. For example, some personal care products, such as face and body wash and toothpastes contain polyethylene and polypropylene microbeads that pose an environmental hazard when disposed of in waste water. Because they pass through sewage treatment plants without being filtered out, their disposal has resulted in plastic particle water pollution.

Watch this video for more information about the microbead dilemma.

The State Water Resources Control Board worked with the Southern California Coastal Water Research Project (SCCWRP) to address issues with CECs through a Science Advisory Panel that has developed recommendations for monitoring strategies for CECs. See SCCWRP’s CEC Factsheet.

What are the Effects of Water Pollution?

Beach Closures

Photo Credit: www.sdnews.com

Photo Credit: www.sdnews.com

Have you ever gone to your favorite beach and found that it has been closed due to high bacteria levels? Pathogens (disease-causing viruses and bacteria) originating from human or animal waste can enter the ocean from polluted runoff, as well as accidental releases from sewage treatment facilities, ranches and farms. Runoff from urban areas or discharges from improperly maintained sanitary systems on boats are also sources of harmful viruses and bacteria. Humans aren’t the only ones at risk from bacteria in the ocean. For example, the population of southern sea otters is threatened by a parasitic pathogen, called Toxoplasma gondii, which is hosted by cats and is spread through their feces. Once established, the parasite causes brain damage and often death in marine species.

Download the free Waterkeeper Swim Guide app to explore California’s beaches and see if they are open for swimming or if the water quality is poor.

Harmful Algal Blooms

Phytoplankton are microscopic single-celled organisms that exist at the base of the food chain in most freshwater and marine ecosystems. The oxygen for every other breath we take comes from the ocean, as a result of marine phytoplankton photosynthesis.

Phytoplankton - Sally Bensusen, NASA EOS Project Science Office

Phytoplankton – Sally Bensusen, NASA EOS Project Science Office

When there is an oversupply of nutrients and ideal physical conditions, phytoplankton can form algal blooms. An algal bloom which threatens or damages the environment, human health or surrounding economies is considered a Harmful Algal Bloom, or HAB. Algal blooms can occur naturally or can be triggered by pollution. In California, the HAB groups of greatest concern are Pseudo-nitzschia, Alexandrium, Heterosigma and Microcystis. Certain species can produce toxins that are harmful to humans and marine mammals, which include domoic acid, paralytic shellfish poisoning and cyanotoxins.

Nitrates and phosphates are nutrients that plants need to grow. In small amounts they are beneficial to many ecosystems. In excessive amounts, however, nutrients cause a type of pollution called eutrophication. For more on eutrophication, visit the NOAA Ocean Service’s education tool kit and a short video from NOAA about eutrophication.

The California Department of Public Health coordinates a routine monitoring program along the California coast to sample mussels and other shellfish like clams and scallops for the presence of paralytic shellfish poisoning and domoic acid toxins. Commercial shellfish harvesters are also required to provide weekly shellfish samples to the California Department of Public Health for paralytic shellfish poisoning toxin assay and domoic acid analysis. If toxin levels are high enough, warnings and quarantines are issued to protect the recreational fishing public and shellfish consumers.

Mercury In Seafood

Image Credit: KidSafe Seafood

Image Credit: KidSafe Seafood

Ocean pollution can also come from airborne sources. Coal-fired power plants and chlorine factories release mercury into the air, which eventually settles into the ocean. Mercury is a neurotoxin that can cause damage to the brain and nervous system. Mercury enters the systems of marine organisms and bioaccumulates, or increases, as larger fish eat smaller fish contaminated with mercury. Top predators in the ocean, such as swordfish, sharks and tuna, often have the highest concentrations of mercury. For this reason, doctors recommend limiting the consumption of some types of fish and shellfish. For more information on which fish and shellfish to avoid, consult the Monterey Bay Aquarium’s Seafood Watch Guide or the U.S. EPA’s website. To learn more about which fish are safe for pregnant women and children, visit the KidSafe Seafood website.

What is the State of California Doing?

Water Quality

This rain garden is an example of low impact development. Photo Credit: Jefferson County Department of Health

This rain garden is an example of low impact development. Photo Credit: Jefferson County Department of Health

The State Water Resources Control Board (State Water Board) is responsible for protecting ocean water quality for the enjoyment of residents, businesses, and tourists. The State Water Board regulates the discharge of treated water, including discharge to the ocean and beaches.

Low impact development is a strategy that incorporates permeable surfaces, such as green roofs and bioswales, to reduce the amount of polluted runoff that enters storm drains. In May 2008, the California Ocean Protection Council (OPC) passed a resolution to support the use of these eco-friendly strategies.


Clean Beaches

California has one of the most popular coastlines in the country, and keeping its beaches healthy is a top priority. California beaches see about 150 million day visits by tourists and residents each year to swim, wade, surf and dive. Beach visitors spend over $10 billion each year in California. To protect this important asset, California has the most extensive and comprehensive monitoring and regulatory program for beaches in the nation.

California has invested $100 million in Clean Beach Initiative grants to fund local projects that reduce bacterial contamination along the coast. The state has also funded research to develop more rapid detection methods for determining when to post beach closure signs, track the sources of contamination and better understand the relationship between bacterial indicators and incidence of disease.

Watch this video to learn more about the Clean Beach Initiative.

For a comprehensive analysis of beach water quality in California see Heal the Bay’s Beach Report Card that grades 500 beaches a week based on the previous 30 days of monitoring results. Check back often for the latest grades!

Areas of Special Biological Significance

In an effort to preserve biologically unique and sensitive marine ecosystems for future generations, California has designated thirty-four coastal areas as Areas of Special Biological Significance (ASBS). These areas were established in the 1970s, and they cover roughly 500 miles (32%) of state shorelines (mainland and Channel Islands). The California Ocean Plan requires protection of the species and biological communities in these areas from undesirable alteration in natural water quality through the prohibition of waste discharge. ASBSs belong to California’s network of Marine Managed Areas and many are co-located with Marine Protected Areas. For more information about these areas, visit the State Water Board’s website.

Watch this video for more information about Areas of Special Biological Significance.

What is the Federal Government Doing?

The White House’s National Ocean Council created the National Ocean Policy Implementation Plan to “address some of the most pressing challenges facing the ocean, our coasts and the Great Lakes.” This plan includes several actions to reduce the impacts of point and nonpoint sources of nutrient pollution, such as reducing rural and urban sources of excessive nutrients, sediments, toxics and pathogens, minimizing impacts of hypoxia and HABs, and addressing the threats caused by toxic chemicals and land-use practices.

The U.S. Environmental Protection Agency’s (EPA) Office of Water operates under a number of federal mandates to prevent water pollution and enact measures to improve water quality, including the Clean Water Act, the Marine Protection, Research, and Sanctuaries Act, the Beaches Environmental Assessment and Coastal Health Act and the Coastal Zone Management Act, among others. Some of the programs developed by the EPA to satisfy these mandates include Green Infrastructure/Low Impact Development, a pollution discharge permit program, a storm water program and the wastewater management office.

For more information:
National Ocean Service: nonpoint source pollution education kit.
EPA, Office of Wetlands, Oceans, and Watersheds — The EPA Office that jointly administers the Coastal Nonpoint Pollution Control Program with NOAA.
NOAA’s Clean Marina Website — The Clean Marina Program is a voluntary, incentive-based program that helps states address nonpoint source pollution from marina and boating activities.
U.S. Food and Drug Administration: Addresses potential radiation, water pollution, and seafood contamination from the Fukushima disaster in 2011.

Thank You Ocean Videos Related to Water Pollution

Storm Water Runoff (February 1, 2015)
The Microbead Dilemma (January 26, 2016)
Channel Islands Bald Eagle Restoration (May 19, 2014)
Should We Fear Red Tides? (July 22, 2013)
Rain Garden: Slowing Pollution at Its Source (November 26, 2012)