How to Prevent Agricultural Nonpoint Source Pollution
Best Management Practices
Methods and procedures that prevent or reduce pollution are known as
best management practices (BMP). The following list of best management
practices reduce agricultural nonpoint source pollution.
Sediment
- Practice conservation tillage. To control erosion, leave at least
a 30 percent residue from the previous crop on the soil surface after
planting the new crop.
- Leave as many areas in grass as possible to reduce erosion and intercept
sediment from fields. Do not plow turnrows, field borders, or traffic
lanes. Use strip cropping, vegetative filter strips, and borders.
- To control erosion from raindrops, plant a cover crop or green manure
crop during fallow years and leave crop residue on fields in winter.
- Install grassed waterways and vegetative filter strips in and around
fields.
- Convert highly erodible cropland areas to grass or trees.
Nutrients
- Perform soil analysis on a regular basis to determine fertilization
rates needed to achieve desired yields. Never overfertilize.
- Reduce autumn use of nitrogen fertilizers and band fertilizers where
possible.
- Apply fertilizer in split applications at the proper time to reduce
potential loss from one heavy application. Monitor soil pH to achieve
maximum use of phosphates.
- Employ contour farming and soil conservation practices to reduce erosion
and prevent run-off containing sediment and nutrients. Use crop residues,
forested streamside management zones, buffer strips, and grassed waterways
to trap sediment that may have attached fertilizer particles.
- Reduce the need for fertilizer with cover crops, including legumes
and green manure crops.
Pesticides
- Use integrated pest management techniques, scouting fields often.
Spray insecticides only when pest populations warrant application, the
possibility of drift is low, and run-off is at a minimum.
- Maintain spray equipment in good working order. Never overfill spray
tanks.
- Utilize crop rotation, strip cropping, and field borders to minimize
the need for pesticides.
Animal Wastes
- Evaluate your operations to prevent animal wastes from contaminating
water sources. Install waste management measures such as no-discharge
lagoon systems and composting bins.
- Check waste management systems and practices regularly to be sure
they are functioning properly and follow a regular maintenance schedule.
- Use animal wastes in an approved manner as a soil amendment on crop
and pasture lands.
- Properly treat all wastes or waste water discharged into surface waters
after obtaining a permit from LDEQ authorizing discharge.
More Information
The following projects can serve as a starting point for more information.
The Statewide
Nonpoint Source Educational Program encompasses a variety of initiatives
to educate farmers about measures to reduce nonpoint source pollution.
It is managed by local units of government, operating under the guidance
of the Louisiana Department of Agriculture and Forestry/Office of Soil
& Water Conservation.
Nonpoint source pollution is one of several targets of the Pollution
Prevention Plan. Jointly created by government agencies (such as the
Louisiana Department of Environmental Quality), academic institutions,
industry associations, and citizen groups, the goal is to produce model
pollution prevention plans (consisting of the most effective best management
practices) for each segment of the agricultural industry.
The Farmstead
Assessment System (Farm*A*Syst) assists farmers who need to close
an abandoned well, build a farm chemical storage facility, a mixing and
loading area, or construct/modify livestock management facilities. The
project is a collaborative effort between federal, state, and local agencies.
The Coastal Nonpoint
Source Program targets the special needs of coastal regions.