Shoal Creek Watershed TMDL Implementation Plan Illinois Environmental Protection Agency
16 Final Report
Table 4-6. Cost Calculations for Filter Strips Used in Crop Production.
Item
Costs Required to Treat One Acre of
Agricultural Land with Filter Strip
Construction Costs $0.30
Annual Maintenance Costs $0.01
Construction Costs $261
System Life (years) 20
Annualized Construction Costs $13
Annual Maintenance Costs $8.70
Annual Income Loss $3.50
Average Annual Costs $25/ac treated
Filter strips used in animal operations typically treat contaminated runoff from pastures or feedlot areas or
washings from the milk houses of small dairy operations (NRCS, 2003). The NRCS (2003) costs for
small dairy operations (75 milk cows) assumes that a filter strip area of 12,000 square feet is required.
For the pasture operations, it is assumed that a filter strip area of 12,000 square feet (30 ft wide and 400 ft
long) would be required to treat runoff from a herd of 50 cattle (NRCS, 2003). The document does not
explain why more animals can be treated by the same area of filter strip at the dairy operation compared
to the pasture operation.
For animal operations, it is not likely that land used for growing crops would be taken out of production
for conversion to a filter strip. Table 4-7 summarizes the capital, maintenance, and annualized costs for
filter strips per head of animal.
Table 4-7. Cost Calculations for Filter Strips Used at Animal Operations.
Operation
Capital Costs per Head
Annual Operation and
Maintenance Costs
per Head
Total Annualized
Costs per Head
Small dairy (75 milking cows) $48 per head of cattle $1.50 per head of cattle $4 per head of cattle
Beef or other (50 cattle) $72 per head of cattle $2.50 per head of cattle $6 per head of cattle
4.6 Grassed Waterways
Grassed waterways are stormwater conveyances lined with grass that prevent erosion of the transport
channel. In addition, the grassed channel reduces runoff velocities, allows for some infiltration, and
filters out some particulate pollutants. Grassed waterways are used in animal operations to divert clean
water away from pastures, feedlots, and manure storage areas. A grassed waterway providing surface
drainage for a corn field is shown in Figure 4-4.
