FAQs about Nonpoint Source Pollution

Who causes Nonpoint Source Pollution?

We all do. When you spill gas at the pump or dump antifreeze on the ground, you contribute to NPS pollution. NPS pollutants in our waters threaten humans and wildlife, so the reauthorized Clean Water Act now requires Tennessee to have a Nonpoint Source Program to reduce water pollution from runoff. Experts in Tennessee have worked hard to resolve the problem. Here is where many of these pollutants come from:

  • Urban Runoff: Chemicals and fertilizers used on grass or in gardens, along with car emissions, oil, antifreeze, paint, battery acid, pet waste, household cleaners, and other impurities can get into our water. They are carried by runoff from parking lots, driveways, lawns, through storm drains and melts, or placed on the ground by unsuspecting homeowners.
  • Septic Systems: These home treatment systems filter waste through the soil. When they are improperly maintained, or poorly located, waste may emerge at the surface where it can be washed into streams and lakes by rain, or it can seep directly into groundwater. About 40% of Tennesseeans get their water from wells, and waste from faulty septic systems may enter some of those wells.
  • Agriculture: Tons of topsoil wash off cultivated fields every year in Tennessee and much of it ends up in streams and lakes. The problem grows when fertilizers and pesticides applied to that soil get washed into the water. Improperly managed waste from livestock also damages streams and lakes, robbing them of oxygen.
  • Forestry: Poor logging roads and the skid trails made as timber is dragged from an area can cause erosion. Operating machinery in or near a stream can also cause erosion.
  • Mining: When mines are not properly constructed, operated, or reclaimed, they cause significant NPS pollution. Sediment is washed into streams when reclamation is inadequate. The impurities in coal create acids when exposed to water and air, and these acids often wash into streams or seep into groundwater.
  • Construction: When soil is disturbed by grading work and BMPs are not properly used and maintained, sediment may enter streams, rivers and lakes through runoff. Oils, paints, cleaners and other pollutants used in construction can also damage our waters.
  • Stream Projects: Dredging, channelization, and other stream alteration projects damage water quality when tons of silt, rock, and debris are disturbed. The debris moves into other areas of streams or lakes, smothering aquatic life and destroying aquatic habitat.

What can be done to reduce Nonpoint Source Pollution?

Tennesseans from many fields came together to find solutions called Best Management Practices (BMPs), that can reduce NPS pollution. There are BMPs for farmers, foresters, developers, miners, industrial workers and homeowners. These practices include good housekeeping at home and work, following label instructions for pesticides and using specific methods to till land, reclaim mines, build roads and harvest trees.

Lakes, rivers and streams cover Tennessee, entertaining and sustaining us. We swim and fish in these waters, and use billions of gallons each year in our homes and cities. Beneath our feet, groundwater crisscrosses the state in huge unseen aquifers, feeding the wells of half of all Tennesseans. From Memphis to Mountain City, we depend on water more than anything else in our lives, and yet, we add to its pollution.

Hasn’t Tennessee been successful with efforts to stop water pollution?

Yes, partly. Billions have been spent since the mid-1900s to enhance water quality. We have reduced the discharge of untreated wastewater. In 1946 not a single Tennessee industry and only ten of the state’s cities were equipped to treat wastewater. Today, there are 925 individually permitted point source discharges in Tennessee.

We will always need to monitor facilities that send treated wastewater into our rivers and correct problems as they occur, but Tennessee is threatened with an even more complex water quality dilemma--NPS, also called runoff. It will take widespread cooperation to control it.

What is Nonpoint Source Pollution?

Nonpoint Source (NPS) Pollution, or runoff, is a drop in water quality caused by contaminants entering streams and lakes from places that not easy to find. Unlike pollutants that come from "point" sources like the discharge pipes of wastewater treatment systems, pollutants from "nonpoint" sources enter our waters through many different paths.

For example, NPS pollutants enter our streams and lakes when it rains. Runoff from rain carries soil, pesticides, fertilizers, paints, motor oil, animal waste, antifreeze and salt, that have been sprayed, laid, poured or spilled on the ground. These pollutants enter our waters through storm drains, ditches, culverts, gullies and other manmade or natural channels.

How serious a threat is Nonpoint Source Pollution?

A 2000 report on the status of Tennessee’s water reveals that 7.6 percent of sampled river miles are too polluted to support at least one of their desired uses (drinking, swimming, fishing, etc.) and 23.5 percent are only partially supporting. Of the sampled acres of lakes in Tennessee, 17 percent fail to fully support all uses, and 5.2 percent are partially supporting. Today, NPS pollution causes more harm to our waters than do discharges from wastewater treatment systems and other point sources. According to reports from the EPA, about 40 percent of waters nationwide are affected by NPS pollution.

Is runoff the only nonpoint source of pollution?

No. Runoff is the largest source of NPS, but there are many more ways streams and lakes can be impacted. Airborne pollutants, such as heavy metals from automobile exhausts or acid rain can be causes of NPS pollution when blown into the water.

  • Urban runoff includes motor oil and gasoline from roads, fertilizer and chemicals from lawns, and sewage from septic tanks.
  • Agricultural runoff may contain animal wastes from livestock operations, fertilizer and weed killers from croplands, and soil washed off newly plowed fields.
  • Runoff from forestry operations includes soil from haul roads, weed killers and fertilizers. As a percentage, forestry does not contribute much to overall nonpoint source pollution in Tennessee.
  • Abandoned mines (from resource extraction), are sites from former mining operations where metals such as copper, zinc, barite and iron were mined as well as clay and rock. In Tennessee, there are many abandoned coal mines as well. The mine sites contribute metals such as iron, sediment and wastes which often upset the pH balance (acidity or alkalinity) of the water, making the water too acidic and creating an environment where fish and other aquatic organisms can’t survive.
  • Hydrologic modification includes building dams and diverting stream channels. This upsets the stream’s natural chemistry and adds sediment to the stream.
  • Development projects and road and bridge construction add sediment and strip the stream banks of plants and trees which are necessary to provide stream bank stability, shade and temperature control for aquatic organisms (animals that live in the water) and create homes or habitat for wildlife.
  • Land Disposal includes septic systems and illegal dumps.

Where Does the Funding Come From?

There are two types of nonpoint source funding; the base grant and incremental. Included in the base grant is the Targets of Opportunity: Grant Pool, or simply the grant pool, which was established by the Department of Agriculture in 1998. The purpose of the grant pool is to provide funding for individual watersheds that are listed on the state’s 303 (d) list or 305 (b) list as impaired or not meeting all of their designated uses. The 303 (d) list and 305 (b) list were developed by the Tennessee Department of Environment and Conservation Division of Water Resources. They list the streams and rivers not meeting their designated uses, such as fishing or swimming. The grant pool funding is usually granted to the Soil Conservation Districts or Resource Conservation and Development Districts for the purpose of identifying the causes of impairment, and implementing BMPs to improve water quality in an attempt to remove the stream from the 303 (d) list or 305 (b) list.

In addition to the base funding is the Unified Watershed Assessment (UWA) incremental fund, which is a separate source of money from EPA that was set aside as part of the Clean Water Action Plan. Like the grant pool funding, UWA grants are limited to streams on the 303 (d) list or 305 (b) list. Funding is awarded in order to implement BMPs to address the type of impairment affecting a particular waterbody in order to eventually remove it from the 303 (d) list or 305 (b) list. The first UWA grant was received in 1999. Priority watersheds were chosen by a team consisting of members of the Department of Agriculture Nonpoint Source Program (NPS) and Agricultural Resources Conservation Fund (ARCF), the Tennessee Department of Environment and Conservation Division of Water Resources (TDEC-WR), and the Natural Resources Conservation Service (NRCS). There are eleven UWA watersheds in the state.

Base and incremental funds are matched 40% non-federal funds. Sources of cost-share include TDEC, the Tennessee Wildlife Resources Conservation Agency, local governments, non-profit organizations, and landowners.

The Ag Resources Conservation Fund is part of TDA’s Administration and Grants section. Like the NPS Program, it aims to control erosion and address nonpoint source pollution by providing cost-share to farmers and landowners. However, the ARCF addresses BMPs on agricultural lands only. The Agricultural Resources programs are administered locally by Soil Conservation Districts (SCDs) that also provide technical assistance for BMP implementation. Yearly allocations are made to the SCDs based on certain priority practices and expected participation by farmers, which is entirely voluntary. The voluntary approach has been tremendously successful in helping to solve many of the problems caused by agricultural NPS pollution. The ARCF employs eight environmental specialists to work with the SCDs and the RC&Ds to provide technical assistance to farmers and landowners to implement BMPs.