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Nitrogen is a powerful nutrient. It can make grass green and dramatically increase corn yields. Yet when too much of it reaches our rivers and streams, it threatens human health, chokes out aquatic life, and fouls our coastal waters.
For example,
there
is abundant scientific evidence that nitrogen contributes to
the
growing “Dead Zone” in
the
Gulf of
Mexico
.
In 2001,
the
U.S. Environmental Protection Agency (EPA) determined that
the
nation needs to reduce excess nutrients, such as nitrogen, in our streams and rivers.
Currently, state EPAs are mandated by
the
federal EPA to write and enact water quality standards for nitrogen and phosphorus or to adopt
the
proposed federal criteria. In response,
Illinois
water reclamation districts predict1 it will cost
their
ratepayers more than $5 billion to install
the
best technology availableand $500 million annually to operateyet even this investment will not produce water that meets
the
proposed federal criteria. Nor will it address the region’s needs for open space, wildlife habitat, and flood control.
The Wetlands Initiative and its partners have developed an alternative: Restored wetlands, financed by
the
purchase of nutrient removal credits, either through an open market or through long-term contracts. We call this strategy “nutrient farming.” In addition to removing nutrients,
the
restored wetlands will provide important environmental benefits for humans and wildlifebenefits that are unavailable through
the
use of traditional treatment technologies.
The potential market for nutrient credits is huge. For example, an immediate market could be industrial and municipal dischargers. Annual operating and maintenance costs at upgraded treatment plants are estimated to be $4.8 billion nationwide (extrapolated from
Illinois
per capita costs). This money would be better spent re-creating wetlands, which provide many other environmental benefits.
Nutrient farming could be conducted throughout
the
Mississippi
River Basin
and other watersheds across
the
United States
where high nutrient concentrations are of concern.
Problem
The regions with
the
highest losses of presettlement wetlands are also
the
areas with highest fertilizer usage and nitrogen yields. In
the
past 200 years, for example, three Midwestern states ( Iowa
,
Missouri
,
Illinois)
in
the
Upper
Mississippi
River Basin
drained 85 to 90 percent of their wetlands. More than 4 million acres of wetlands were destroyed in
the
Illinois River
watershed alone. Not surprisingly,
these
areas also have
the
highest nitrogen concentrations in
their
rivers.
The modern, highly modified aquatic ecosystems of
the
upper
Midwest
can no longer purge
themselves
of excess nitrogen. By dredging, channelizing and leveeing off rivers from
the
ir backwater lakes and floodplain wetlands, we have crippled
the
river’s natural ability to denitrify its waters. Today,
the
nutrient-rich water reaching
the
Gulf of
Mexico's
coastal shelf, triggers excessive algal growth. This results in low oxygen levels (called hypoxia), causing fish, shrimp, crabs, and zooplankton to die. Scientists also have linked excess nitrogen to bladder cancer and blue-baby syndrome.
The altered river systems of today cause billions of dollars in flood damage as well. According to
the
U.S. Weather Bureau, national flood damages now average $3.5 billion; earlier in
the
century (1903-1933), damages averaged $1.4 billion (both sums are adjusted for inflation). This increase is in spite of or because ofever-rising federal spending on levees and other structures.
Solution
Nutrient farming is a control strategy that seeks to optimize
the
natural chemical and biological reactions in created and restored wetlands to remove nitrogen and phosphorus from the water and carbon from the air. Landowners
then
sell nutrient reduction credits to other farmers, municipalities, or industries that release excess nutrients to surface waters and cannot cost-effectively remove
these
nutrients
themselves
.
The Wetlands Initiative is developing the Goose Pond Nutrient Farming Pilot Project to test and demonstrate
the
economic efficiency and environmental benefits of nutrient farming. This new way of managing
the
quality of our nation’s waters will be less costly than conventional treatment methods, reduce demand on energy resources and provide additional benefits for biodiversity and wildlife.
Nutrient farming must be viewed as a business enterprisean economically efficient means to manage environmental problems. This economic efficiency will be established only by using solid biogeochemical and economic data.
1Zenz, D. R. 2003. Technical feasibility and cost to nutrient standards in
the
state of Illinois, Report commissioned by
the
IL Assn. of Wastewater Agencies.
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