Nutrient and Sediment Removal by Vegetated Filter Stips

A field study utilizing simulated rainfall and bare plots 5.5m wide by 22m long was conducted to study the effectiveness of vegetated filter strips 4.6 and 9.2m long in
removing nutrients and sediments from agricultural runoff. Losses of N and P from
plots with filters were highly variable as compared to plots with no filters. Generally,
nutrient removals appeared to be greater with the longer filters, but decreased as the
number of runoff events increased. Mass losses of TSS, TN and TP in surface runoff
were reduced by 66%, 0% and 27%, respectively, by 4.6m (15ft) long filters. TSS, TN and TP reductions by 9.2m (30ft) long filter strips of the lengths utilized in this study were effective in removing sediment from runoff but should not be relied upon as the primary means to reduce nutrient losses from agricultural areas.