Vegetative Filter Treatment of Livestock Feedlot Runoff

Four vegetative filters were installed on feedlots in central and northern Illinois. Two configurations were used: channelized Dow and overland Dow. After settling for partial solids removal, runoff was applied directly to the filters and allowed to Dow from the inlet to the outlet section. Results from measurement analyses and sampling of influent, effluent, and surface Dow at intermediate points were reported. Most runoff events were infiltrated completely, resulting in no filter discharge. Runoff from larger events was partially discharged. Filters removed as much as 95% of nutrients and oxygen-demanding materials from the applied runoff on a weight basis, and 80% on a concentration basis. Removal was directly related to Dow distance or contact time with the filter. Channelized Dow with greater Dow depths required greater contact time or Dow distance than shallow overland Dow to achieve the same level of treatment