1. What is nutrient farming?

Nutrient farming is an ecological and economic strategy to improve water quality in our rivers and streams by using constructed or restored wetlands to remove excess nutrients—such as nitrogen, phosphorus, and carbon—from the water. The landowner who constructs or restores the wetlands is the “farmer” who “harvests” excess nutrients, selling the nutrient removal credits. Buyers of the se credits will be wastewater treatment facilities or other industries who release excess nutrients into the water, but cannot cost-effectively remove them themselves .

2. How does a wetland remove nutrients from water?

When water rich with nitrogen, for example, enters a wetland, the nitrogen comes in contact with millions of bacteria that grow in “bio-films” on plants, rocks, and other surfaces in the wetland. These bacteria function as “nitrogen factories,” converting the nitrogen in the water to nitrogen gas. This inert gas is released harmlessly into the atmosphere, which is 78% nitrogen.

3. Why is nitrogen and phosphorus harmful to our water?

Too much of these nutrients fuel an over-growth of algae in a lake or estuary, such as in the Gulf of Mexico. The “Dead Zone” at the outlet of the Mississippi River has roughly doubled in size in the past decade; it is now the size of a small New England state. It appears each summer when massive algal blooms—fed by the nutrients in wastewater discharge and farm runoff in the Upper Midwest —die. Their decomposition robs the water of its oxygen. Fish, shrimp, crabs, and zooplankton also die in this hypoxic zone. The national plan to eliminate the Dead Zone calls for all states in the Upper Mississippi River Basin, including Illinois, to reduce the nutrient load in their rivers and streams.

4. How is a nutrient farm different from so-called “treatment wetlands” that are used by wastewater treatment plants now?

A nutrient farm will be a created or restored wetland that is designed for optimal removal of nutrients. In that respect, a nutrient farm will be like a “treatment wetland” because its primary purpose is to treat water. However, a nutrient farm will be more than just a water treatment plant. The Wetlands Initiative (TWI) expects to design and operate nutrient farms that will support more biodiversity than most treatment wetlands. The impact of biodiversity on nutrient removal will be a research subject in a pilot project being planned by TWI.

5. Has nutrient farming been tried before?

No nutrient farms have been constructed to date. Previous treatment wetlands have only been constructed on a much smaller scale. Also, while a number of water quality credit-trading programs have been formed, none of the m have used wetlands as a vehicle to reduce nutrient levels.

6. How can nutrient farming have a meaningful impact on water quality in the entire Upper Midwest and beyond?

Many environmental problems in the Midwest —diminished water quality, flood damage, and reduced biodiversity and wildlife habitat—are attributable to the wholesale loss of millions of acres of wetlands over the past two hundred years. We believe that if many of the se lost wetlands can be restored, these problems can be successfully addressed. But the big, unanswered question in the wetland restoration equation has always been, “How do we pay for it?” To answer that question, TWI developed the strategy of “nutrient farming,” believing that if landowners could be compensated for harvesting nutrients from water flows that enter restored wetlands, then large-scale wetland restoration would follow.

7. How will nutrient farming compensate landowners for restoring wetlands?

A landowner will construct or restore a wetland and manage it (e.g., control the water level and flow rate) for optimal nutrient removal. The nutrient level in the inflow can be compared to the outflow and the difference is called a “nutrient removal credit.” These credits will then be sold to entities who view this as the most cost-effective strategy to meet their pollution control obligations.

8. Has the sale of nutrient removal credits been tried before?

The trading of pollution reduction credits is not new. A market for trading air quality credits to reduce acid rain pollution was established in 1995. Since 2003, the U.S. Environmental Protection Agency (EPA) has been actively promoting water quality credit trading in general, and, recently, stated that it supports the development of a nutrient farming pilot project.

9. What will drive the creation of the water quality trading market?

Wastewater discharge operators and other industries will soon face huge capital costs for new or expanded treatment plants to meet pending water quality standards. Farmers are also under increasing scrutiny, because agricultural fields are a disproportionately large source of nutrients entering our waterways. (Nutrient discharge from agricultural fields, however, is not currently regulated.) As states adopt water quality standards requiring point dischargers such as wastewater treatment facilities and industries to reduce nutrient loads and concentrations, the pressure on dischargers to find a low-cost treatment option will intensify. The economics of this picture strongly favors the adoption of the kind of cost-effective solution offered by nutrient farming-based trading of water quality credits.

10. Doesn’t the trading of water quality credits amount to a license to pollute?

Any strategy for trading water quality credits assumes that government agencies such as EPA will have set a limit on the amount of pollution allowed within a watershed or in a body of water. Credit trading the n becomes an option for affected dischargers to work as a collective to reach that limit. The end result will be an overall decrease in the nitrogen and phosphorus load entering the Mississippi River, which would be good news for the Gulf of Mexico.

11. What about the water quality of Illinois streams and rivers that would transport nutrient-rich water to nutrient farm wetlands?

Ideally, it is best to treat water as close as possible to the source of discharge. Many nutrient farms could be built near the sources of nutrients. This would be the case with respect to agricultural fields as well as municipal wastewater treatment plants downstate, the reby benefiting many of the state’s rivers and streams. Unfortunately, where Chicago is concerned, large tracts of land for nutrient farming are not available; thus, nutrient farms that treat Chicago ’s nutrient load (primarily from wastewater treatment plants) would need to be located downstream. This would not pose a concern for human health, since the degraded upper reaches of the Illinois River are not used for drinking water.

12. What happens to mercury and other heavy metals that would reach nutrient farms?

The primary source of mercury in our rivers and streams is rainfall carrying airborne mercury that is released from coal combustion and in connection with o the r industrial processes. Once in the waterways, mercury and other heavy metals generally find their way to the bottom of our rivers, streams, and wetlands. The U. S. EPA and others are sponsoring research to learn more about what this means for our water supply. Obviously, the best way to attack this problem is through better air pollution control and enforcement measures.

13. What questions does TWI want to answer with a nutrient farming pilot project?

The pilot project planned by TWI will focus on what conditions in the wetland would best promote the removal of nitrogen and phosphorus and how the se conditions would affect biodiversity. Although smaller wetland projects have studied the se issues, reliable results cannot be obtained without a large-scale project, on the order of 2,000 to 3,000 acres. Such a project will also help answer questions relating to how landowners are compensated for nutrient farming and provide direction as to what kinds of regulations and credit trading markets are needed to support a nutrient farming strategy. Preliminary studies suggest that the Metropolitan Reclamation District of Greater Chicago could save more than $1.5 billion in construction and operating costs (over a 20-year period) by using nutrient farming to reduce its nutrient load from its wastewater treatment plants. A pilot project will help verify these numbers.

14. In addition to answering questions relating to nutrient farming, what other benefits does TWI anticipate in developing a site for a nutrient farming pilot project?

A nutrient farm would function as a high-quality wetland. As such, in addition to reducing nutrients and improving water quality, it would provide waterfowl and wildlife habitat, store floodwaters, reduce sediment loads, and sequester carbon. Indeed, the fact that a nutrient farm would provide multiple environmental benefits makes this strategy more appealing than traditional treatment methods (e.g., wastewater treatment plants) that provide no benefits other than nutrient reduction and rely on fossil fuels in the treatment process.

15. What is the status of TWI’s efforts with respect to nutrient farming?

TWI has identified a potential nutrient farming site along the Illinois River near its Hennepin & Hopper Lakes project, and landowners at the site have formed a drainage and levee district to participate in the project. TWI has also had discussions with the Metropolitan Water Reclamation District of Greater Chicago regarding the funding of construction costs for a pilot project, and the Board of Commissioners has approved the general superintendent’s request for authority to enter into negotiations for such funding. In addition, TWI staff continues to meet with Congressional representatives and staff of federal agencies to provide information regarding the nutrient farming strategy and to solicit support for a governmental appropriation.

Updated 9/5/06