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| Coastal Watershed FactsheetsEstuaries and Your Coastal WatershedUnited StatesEnvironmental ProtectionAgencyOffice of Water(4504F) EPA 842-F-98-009July 1998 
stuaries are animportant component of the complex and dynamic coastal watershed. The economyof many coastal areas relies on the natural beauty and bounty of estuaries.When those natural resources are imperiled, so are the livelihoods of the manypeople who live and work along the coast. As our population grows, the demandsimposed on our natural resources increase and protecting these resources forall their natural, economic, and aesthetic values becomes even moreimportant.

**What Is an Estuary and What Does It Do?**An estuary is a partially enclosed body of water formed where freshwater fromrivers, streams, and groundwater flows to the ocean, mixing with the saltyseawater. Although influenced by the winds and tides, estuaries are protectedfrom the full force of ocean waves, winds, and storms by the reefs, barrierislands, or fingers of land, mud, or sand that define an estuary'sseaward boundary.

Estuaries come in all shapes and sizes and go by many different names. Theyare often known as bays, lagoons, harbors, inlets, or sounds. Whatever the nameor type, estuaries provide valuable functions.
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- They are critical to the survival of tens of thousands of birds, mammals,fish, and other wildlife. Many different habitat types are found in and aroundestuaries, including shallow open waters, freshwater and salt marshes, sandybeaches, mud and sand flats, rocky shores, oyster reefs, mangrove forests,river deltas, tidal pools, sea grass beds, and wooded swamps.     
- The wetlands bordering many estuaries perform valuable functions includingwater quality and flood protection and water storage. Many upland areas drainto fresh and salt marshes, which act as filters, removing pollution fromrunoff. Wetland plants and soils also act as a natural buffer between the landand the ocean, absorbing floodwaters and dissipating storm surges. Salt marshgrasses, mangrove trees, and other estuarine plants also prevent erosion andstabilize the shoreline.     
- They are a source of recreation, education, and aesthetic value. Boating,fishing, swimming, windsurfing, and bird-watching are just a few of the manyactivities people enjoy in estuaries.     
- Estuaries have important commercial value. They serve as nursery groundsfor two-thirds of the nation's commercial fish and shellfish. Estuariesare also home to ports and marinas that support shipping and other industrialactivities.

**Some Impacts on Estuaries**Pollution of coastal watersheds poses a threat to our nation's estuaries.Some typical impacts on estuarine systems include loss of habitat due todevelopment, loss of recreational opportunities due to poor water quality, andloss of economic resources due to shellfish bed closures and a reduction infisheries.

*People* can adversely affect estuaries. Stresses caused by the overuseof estuarine resources have resulted in reduction in fisheries, loss of habitatand wildlife, and fish kills.

Excessive *nutrients* from sources such as failing septic tanks, sewagetreatment plants, storm water runoff, atmospheric deposition, industrialorganic waste discharge, and contaminated runoff from fertilized farms or yardsor from animal operations can adversely affect estuarine systems. Excessivenutrients in estuaries can result in accelerated eutrophication and algalblooms. As the algae die, they decay and rob the water of oxygen. The algaealso prevent sunlight from penetrating the water. Fish and shellfish aredeprived of oxygen, and underwater sea grasses are deprived of light and candie. Animals that depend on sea grasses for food or shelter leave the area ordie. In addition, the excessive algae growth can result in brown and red tidesand other harmful blooms, such as Pfiesteria piscicida, which have been linkedto fish kills. Increased algae can also cause foul odors and decrease aestheticvalue. 

*Pathogens* are disease-causing microorganisms such as viruses,bacteria, and parasites and can be a result of inadequately treated sewagereleased into estuaries by faulty or leaky septic systems and sewage treatmentplants, runoff from urban areas and animal operations, medical waste, boat andmarina waste, combined sewer overflows, and waste from pets and wildlife. Theycan pose a health threat to swimmers, divers, and seafood consumers. Fish andshellfish concentrate pathogens in their tissues and can cause illness inpeople consuming them.

*Habitat alteration* such as the filling of marshes and tidal flats,and reconstruction of shorelines to accommodate the needs of development,transportation, and agriculture, can degrade estuaries. Wetland loss anddegradation have limited the amount of habitat available to support healthypopulations of wildlife and marine organisms. The clearing of land to obtaintimber, the construction of homes and roads, and other development projectscompleted without properly revegetating the area can lead to excessive*sediments* being washed into the estuarine environment. These sedimentsmuddy the water, preventing sunlight from reaching aquatic vegetation andmaking the water unappealing to swimmers. Sediments can also carry excessnutrients, pesticides, and toxic substances, causing additional water qualityproblems. 

Estuaries are vulnerable to the introduction of a wide variety of *toxicsubstances*. Metals, such as mercury, polycyclic aromatic hydrocarbons(PAHs), polychlorinated biphenyls (PCBs), and pesticides can concentrate in thewater, sediment, and local aquatic animals. These substances enter waterwaysthrough storm drains; industrial discharges; runoff from lawns, streets, andfarmlands; discharges from sewage treatment plants; and atmospheric deposition.Bottom-dwelling organisms like shellfish are exposed to these chemicals and canpose a risk to human health if consumed. Wildlife and aquatic plants andanimals can also be harmed through the consumption of contaminated fish andwater.

Intentional or accidental introduction of *invasive species* can oftenresult in unexpected ecological, economic, and social impacts on the estuarineenvironment. Through predation and competition, introduced species havecontributed to the loss of  some native populations and the drastic reductionof others. Overpopulation of some introduced herbivorous species has resultedin overgrazing of wetland vegetation and degradation and loss of marsh habitat.Other impacts include increased erosion and interference with sport andcommercial fishing and beach use.

*Marine debris* enters an estuary by washing in from storm sewers andwith the tide. Marine debris is one of the more widespread pollution problemsthreatening estuarine and coastal systems. Debris comes from many sources,including improper disposal of trash on land, storm water runoff and combinedsewer overflows to rivers and streams, ships and other vessels, and offshoreoil and gas platforms. Once litter gets into the estuarine environment, itseriously affects wildlife, the environment, humans, and our economy. Coastalcommunities lose considerable income when littered beaches must be closed orcleaned up.

**What Is EPA Doing to Protect Estuaries?**
***National Estuary Program***
-- The National Estuary Program (NEP) was designed to restore and protectAmerica's nationally significant estuaries. Through its approach ofinclusive, community-based planning and action on the watershed level, the NEPis an important initiative in conserving our estuarine resources and aneffective model for the protection and management of other coastal areas. Theprogram focuses not only on improving water quality in an estuary, but also onmaintaining the integrity of the whole system- its chemical, physical, andbiological properties, as well as its economic, recreational, and aestheticvalues. The NEP is designed so local communities can work together to managetheir own estuaries. Each NEP is advised by committees made up ofrepresentatives from federal, state, and local government agencies responsiblefor managing the estuary's resources, as well as members of thecommunity. These stakeholders work together to identify problems in theestuary, develop specific actions to address those problems, and create aformal management plan to restore and protect the estuary. In addition, EPA hasbeen helping NEPs with the assessment of air pollution affecting waterquality.

***EPA's Watershed Approach***-- EPA has joined with others topromote the Watershed Approach nationally as a means to further restore andmaintain the physical, chemical, and biological quality of our nation'swaters. In particular, EPA has been working with federal, state, and tribalgovernments to tailor activities and services to their local watersheds. TheWatershed Approach has three key components:
- Geographic focus-- Watersheds are nature's boundaries, draining tosurface water bodies including lakes, rivers, estuaries, wetlands, streams, andthe surrounding landscape.  
- Continuous improvement based on sound science-- Sound scientific data,tools, and techniques are critical to inform the process. Actions taken includecharacterizing priority watershed problems and solutions, developing actionplans, and evaluating the plans' effectiveness within the watershed.
- Partnerships/stakeholder involvement-- Since watersheds transcendpolitical, social, and economic boundaries, it is important to involve all theaffected interests in designing and implementing goals for the watershed.Watershed teams may include representatives from all levels of government,public interest groups, industry, academic institutions, private landowners,concerned citizens, and others.
- Through the Watershed Approach, integrated coastal management tools andwatershed concepts can be applied in the development of comprehensivemanagement and conservation plans to assess, protect, and restore ournation's estuaries.

***Other EPA Programs***-- EPA's *Coastal WatershedProtection Strategy* specifically targets technical assistance and supporttop priority coastal watershedsF such as NEPs and other coastal watersidentified by states. Through an interagency effort, the *Clean Water ActionPlan* was developed to address enhanced protection of public health fromthreats posed by water pollution, more effective control of polluted runoff,and promotion of water quality protection on a watershed basis. EPA works withcoastal states to develop their *Coastal Nonpoint Pollution ControlPrograms* and with other federal agencies to protect human health andaquatic habitats by reducing marine debris and the discharge of pollutants intoestuarine waters.

**What Can You Do to Help Protect Estuaries?**Estuaries reflect the overall health of a watershed. Individuals are the mostimportant contributors in the long-term effort to identify and address waterquality, pollution, and habitat problems within estuaries. Examine yourevery-day activities and think about how you might be contributing to thepollution problem. Here are some suggestions on how you can make adifference:
- *Be informed and involved.*  Learn about estuarine water qualityand habitat issues that affect the community in which you live and work. Becomefamiliar with your local estuarine systems. Visit or contact your nearbyNational Estuary Program office. Become a citizen volunteer. As a volunteer,you might take ongoing water quality measurements, track the    progress ofprotection and restoration projects, or report on special events such as fishkills and storm damage. You can volunteer to plant trees, to clean up trash, oreven to participate in restoration efforts planting sea grasses and shorelineplants.     
- *Take responsibility for your own backyard.*  Determine whetheradditional nutrients or pesticides are needed before you apply them, and lookfor alternatives where fertilizers and pesticides might run off into surfacewaters and, ultimately, the estuary. Consider selecting plants and grasses withlow maintenance requirements. Water your lawn conservatively; the less wateryou use, the less runoff will eventually find its way into the estuaries.Preserve existing trees and plant new trees and shrubs to help prevent erosionand promote infiltration of water into the soil. Restore bare patches in yourlawn to prevent erosion.     
- *Practice good housekeeping.*  Around the house, keep litter,pet waste, leaves, and grass clippings out of street gutters and storm drainsto prevent their entrance into streams that might flow to estuaries. Never dumpany household, automotive, or gardening wastes into a storm drain. It might endup in an estuary. Keep your septic system in good working order. Replace anydripping faucets or leaky pipes and install water-saving devices in showerheads and toilets. Always follow label directions for the use and disposal ofhousehold chemicals. Take used motor oil, paints, and other hazardous householdmaterials to proper collection sites such as approved service stations ordesignated landfills.       
- *Respect your estuary.*  Avoid entering sensitive habitat areaswith your boat or other motorized watercraft. Maintain your boat engine toprevent oil and gas leaks. Keep all waste produced during your excursions in asafe place to be disposed of properly when you're back on land. Maintainsafe boat speeds to avoid shoreline erosion. Maintain and use your marinesanitation devices properly. Use designated pumpout and dump stations. Maintainyour automobile so that oil doesn't leak and the engine is tuned toconserve energy. By reducing your energy consumption, many tons of nitrogen andtoxic pollutants can be prevented from entering estuaries through emissionsfrom the exhaust system.
**For additional information...**
Call EPA's Oceans and Coastal Protection Division at (202)260-1952.

Also visit the following web sites:
- **Oceans and CoastalProtection**
- **National EstuaryProgram**

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