Managing Runoff from a Small, Paved Beef Feedlot
1983
Each year for 3 y, 56 steer calves were fed to market weight on a corn-silage and shelled-corn ration in a 243-m² paved lot. Storm runoff was measured and sampled as it left the feedlot, and again after it passed through a shallow, concrete settling basin and two consecutive 30 m long by 4.5 m wide sod filter strips. Storm runoff amounts and transport of TS (total solids), COD (chemical oxygen demand), BOD₅ (5-d biological oxygen demand), N (total nitrogen), and P (total phosphorus) were smaller during the fall and winter months, when the steers were small and being fed silage than during May through July, when the animals were larger and eating shelled corn. The settling basin reduced transport of TS and COD by about 55%, while retaining only 35–40% of the BOD₅, N, and P. Total reduction of all parameters was increased to 80–90% in the filter strips. The basin was more effective in large storm events, and the filter strips were more effective when the basin was slowly drained after settling of the settleable solids. Rainfall on the filter strips reduced the concentration of all parameters during large storms, and infiltration during other events reduced transport to downstream areas.
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