Water quality in the United States needs to be improved. Currently, 42% (39%
of rivers and streams, 45% of lakes and reservoirs) of monitored surface water is
considered impaired, indicating that it is no longer suitable for its designated uses such
as drinking, recreation, habitat, food supply, agriculture, and ground water recharge
(USEPA, 2000, Carpenter et al., 1998). Nonpoint source pollution can be associated
with animal manure. This project focuses on two sources of nonpoint source
pollution. The first source is runoff from soils that have been enriched in nutrients
(nitrogen and phosphorus) by manure application. This project evaluates how
effective Alfalfa is at removal of nitrogen and phosphorus from nutrient enriched soils.
It also evaluates the use of USDA’s Plant Nutrient model in association with nutrient
management plans to prevent enrichment of soils. It was determined that Alfalfa is
effective in reduction of nitrogen in soils; however, it was not feasible as a stand alone
practice to remediate phosphorus. The use of USDA’s Plant Nutrient model indicated
that Corn for silage is the most effective crop for reduction of soil phosphorus while
alfalfa and the yields produced in 2004 was the most effective in reduction nitrogen.
However, the model tends to underestimate soil nutrient uptake, so it is important to
have soil tests conducted periodically to prevent nutrient deficiencies. The second
source of nonpoint pollution discussed is runoff from animal feeding operations. This
paper evaluates the effects of grass filter strips in prevention of pollution transport off
of animal feeding operations. It was determined that filter strips with a ratio of runoff
area to filter area of 1:2 is the minimum ratio to effectively prevent nonpoint source
pollution.
