NPS Pollution and You

State's water wealth needs protection

NPS Pollution | Are you a polluter? | Nature responds | Steps to take

Virginia is a water rich state. But plenty of water doesn't necessarily mean having abundant usable water. As with all natural resources, we must use water wisely. We need clean water for drinking, food production, jobs, transportation, recreation, beauty and habitat for some of the most unique natural environs in the world. One of those is among the world's most productive estuaries, the Chesapeake Bay.

Preventing water pollution is difficult, however, because water is dynamic -- it flows freely from property to property, from locality to locality, even from the surface to underground. How water is used upstream can and does affect its quality downstream.

Nonpoint Source Pollution

There's a type of pollution that degrades some of our state's waterways. Its called nonpoint source (NPS) pollution because it doesn't come from a single source, or point, such as a sewage treatment plant or an industrial discharge pipe.

NPS pollution occurs mainly through stormwater runoff. When it rains, runoff from farmland, city streets, construction sites, and suburban lawns, roofs and driveways enters our waterways. This runoff often contains harmful substances such as toxics, excess nutrients and sediments. NPS pollutions effects seldom show up overnight -- they often go unnoticed for years. This characteristic makes it all the more difficult to control.

There are four major forms of NPS pollution: sediments, nutrients, toxic substances and pathogens.

• Sediments are soil particles carried by rainwater into streams, lakes, rivers and bays. By volume, sediment is the greatest pollutant of all. Its caused mainly by erosion resulting from bare land, poor farming practices, and construction and development.
• Nutrients are substances which help plants and animals live and grow. NPS officials are most concerned about excessive amounts of two nutrients; nitrogen and phosphorus. Fertilizer and animal waste are the main sources of these substances.
• Toxic substances are chemicals which cause human and wildlife health problems. They include organic and inorganic chemicals and metals, pesticides, formaldehyde, household chemicals, gasoline, motor oil, battery acid, roadway salt and so on.
• Pathogens are disease-causing microorganisms present in human and animal waste. Most pathogens are bacteria.

Algae blooms can occur when too much nitrogen and phosphorus enter a waterway. Algae block sunlight needed by underwater plants that provide habitat, and algae's decay robs the water of dissolved oxygen needed by aquatic life.

You're probably an NPS polluter

Just about everyone who owns or uses land contributes to nonpoint source pollution. In Virginia, most efforts concentrate on NPS pollution leaving farmland, urban areas, construction sites and forest land. Farms yield sediment, toxic substances and excess nutrients. Statewide, farmland loses several tons of soil per acre per year. While this soil is productive on land, in the water it cuts light needed by aquatic plants, obstructs waterways and covers aquatic habitat with sediment. Worse, soil from farmland sometimes takes with it pesticides and nutrients.

Most of the Virginia's NPS pollution prevention efforts focus on managing nutrients because they pose one of the greatest threats to the health of our waterways and, in particular, to the Chesapeake Bay. Experts estimate that 50 percent of the nitrogen and 29 percent of the phosphorus entering our states surface waters come from farmland. But farms aren't the only source of NPS pollution.

Urban and suburban areas also contribute significant levels of nutrients as well as toxic substances, pathogens and sediment. City streets and other impervious surfaces yield NPS pollutants such as motor oil, gasoline, antifreeze, and other toxic chemicals. Because these surfaces don't absorb rainwater, runoff from urban areas is nine times greater than is that from forest land.

Life in Virginias rivers, streams, lakes and bays could not exist without nutrients, but too much of a good thing often causes more harm than good. Nutrients over-enrich our waterways causing algal blooms which deplete oxygen. This makes the oxygen unavailable to fish and shellfish so they suffocate and die. The algae also cloud the water and coat underwater vegetation, cutting much needed sunlight.

Sediment clouds water too, and it obstructs waterways, clogs sewers, interferes with navigation, and smothers fish and shellfish spawning grounds. Natural erosion and sedimentation occur at a lower rate than that resulting from human land use activities.

Underwater plants and aquatic animals are particularly threatened by NPS pollution. Oysters, shad, herring, striped bass and submerged aquatic vegetation -- considered by many to be the foundation of a stable aquatic ecosystem -- are damaged by this pollution.

No easy answers, but nature responds

The problem is complicated and there are no easy answers, but recent efforts by Virginia and other bay region states show that NPS pollution can be controlled and that nature responds to restoration efforts. For example, trends indicate that striped bass populations in the bay are making a comeback. The best way to solve our NPS pollution problems is through effective local government and individual citizen intervention.  

One gallon of used motor oil can pollute up to 2 million gallons of water.

Steps you can take to help control NPS pollution

Fertilize your lawn and garden according to soil test results. Contact your local extension office agent for instructions. Try to apply fertilizer when heavy rain isn't likely to wash it away.

• Apply pesticides according to instructions on the label.
• Collect litter and animal waste before they wash into storm drains.
• Recycle grass clippings and leaves by mulching or composting. If you can't compost, collect and dispose of yard waste according to local provisions.
• If you change your own oil, take the used oil to a recycling station. Check with your local service stations for such facilities. Never dump oil into a storm drain.
• Home septic tanks should be located, constructed and installed according to regulations. Maintenance and prompt correction of problems are important.
• Direct roof runoff onto a grassed area. Roof drains should not be connected to a sanitary or storm sewer system.
• Watch for soil erosion around your home. Seed, install sod or plant ground cover to protect the site.
• Use porous surfaces such as flagstone, gravel, stone, and interlocking pavers rather than concrete and asphalt.
• If you're concerned about the effects of runoff leaving a nearby construction site, contact the local governing body responsible for erosion and sediment control in your area. Most land disturbance is regulated by local ordinances under the Virginia Erosion and Sediment Control Law.
• Be active! Join a civic or environmental group and participate in stream cleanup activities. Give talks, man booths, volunteer in river cleanup activities such as DCR's Adopt-a-Stream... spread the word.

You couldn't live long without clean water. Nothing can. Above are just a few simple ways you can do your part to give something back to our waters.