Frequently-Asked Questions
Why do nutrient loadings to some rivers and streams need to be reduced?
As of 1996, about 40% of the nation's surveyed rivers, lakes, and estuaries were too polluted for basic uses like fishing and swimming. High concentrations of nutrients were one of the leading causes of water quality problems. The 2000 National Water Quality Inventory revealed that nutrients are the most widespread pollutants impacting surveyed estuaries; and nutrients and metals are the most widespread pollutants impacting surveyed lakes. Aquatic ecosystems require some nutrients in the water; but excessive amounts of nutrients can harm aquatic life and human health. For example:
- High concentrations of phosphorus are often responsible for accelerated eutrophication in lakes, streams, and reservoirs. Eutrophication can lead to algal blooms, fish kills, foul odors, and excessive aquatic weed growth.
- Drinking water with high concentrations of nitrate (a form of nitrogen) can reduce oxygen transport in the bloodstream. In extreme cases, this can lead to "blue baby syndrome" in infants. The EPA has set a maximum contaminant level of 10 mg/L (as nitrogen) for nitrate in drinking water because of these concerns.
- High concentrations of ammonia (another form of nitrogen) can be toxic to fish and other aquatic organisms.
- When excessive amounts of phosphorus and nitrogen flow into coastal waters, areas of extremely low dissolved oxygen (hypoxia) can develop. These areas are popularly known as "dead zones" because they contain too little oxygen to support fish and other organisms. Click here to find out more about hypoxic zones in the Gulf of Mexico, the Chesapeake Bay, and elsewhere.
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How can nutrient trading be used to reduce nutrient pollution?
Nutrient trading can be used to reduced nutrient pollution within the context of a mandatory cap on the total quantity of nutrients entering the water, or within the context of a voluntary, open program with a percentage reduction goal. In either context, the goal is to cost-effectively reduce the amount of nutrients that enter a waterway.
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How can trading benefit me and my watershed?
In addition to the environmental benefits associated with having lower levels of nutrients in the water, trading can generate these economic benefits:
- Point sources with high control costs benefit from paying less to achieve a given reduction in nutrient loadings.
- Point and nonpoint sources with lower control costs benefit from getting financial support for reducing nutrient loadings. This can help them overcome up-front costs that prevented them from taking additional action in the past.
- The community in the watershed benefits from having water quality goals met at a lower overall cost. People get waterways fit for swimming and fishing without unnecessarily taking scarce dollars away from schools and other uses.
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Where is nutrient trading being tried?
Nutrient trading is being considered or tested in several watersheds around the country. See the list of pilot trading programs and groups investigating trading to learn more about individual programs.
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Why is trading being considered now?
Over the past 25 years, most efforts to improve water quality in the United States have fallen into one of two categories:
- regulatory requirements for point sources: sources like municipal and industrial treatment facilities that have an identifiable point of discharge like a pipe; and
- voluntary programs for nonpoint sources: sources of pollution that are dispersed across the landscape, such as runoff from urban areas or agricultural fields.
Controls on point sources have become tighter over time, leading to ever higher control costs. These controls have produced significant improvements in water quality. Yet greater pollution reductions are needed on many waterways to meet the goals of the Clean Water Act, the main federal law protecting water quality. Waterways with persistent water quality problems are now subject to a more stringent approach under the Clean Water Act, known as the Total Maximum Daily Load (TMDL) process. Trading--whether between point sources or among point and nonpoint sources--is seen as a promising way to meet water quality goals at lower cost, especially within the context of the TMDL process.
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What can I do with the tools in NutrientNet?
This web site is designed to help you explore watershed-based trading as a policy option for addressing water quality concerns. If you live in one of the watersheds with a pilot trading program (see the next section), you can use:
- NutrientNet as an estimation tool to assess whether or not you should participate in the nutrient reduction market. NutrientNet allows you to take a first-cut look at the quantity of reductions that might be possible for you and at the likely costs of making the reductions. NutrientNet provides users, especially farmers (nonpoint sources) with a means of assessing the current baseline nutrient load and potential reductions achieved through implementation of best management practices. Farmers will need to verify the results with an extension agent or similar expert who is familiar with your operations for the reduction credits to be registered.
- The Market section to review and post offers to buy and sell nutrient reductions. The section also provides a summary of market activity for each watershed.
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Where is NutrientNet being used?
NutrientNet is being used in the following watersheds:
- Kalamazoo River, MI
- Chesapeake Bay/Potomac River
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Can NutrientNet be adapted for use in my watershed?
If you would like to use NutrientNet to explore trading as an option for your watershed, please contact Mindy Selman for more information.
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