How Well Do Lawns Filter Runoff?
Dig Deep for the Answer. By John Barten, Water Quality Manager- Hennepin Parks in Minneapolis/St. Paul, Minnesota With the coming of summer, local, regional and statewide publications have been printing numerous articles extolling the virtues of lush green lawns as filters for runoff water, and encouraging the use of fertilizers and herbicides to grow these lawns. As concerned lake users, we need to be aware of the limitations of lawns as runoff filters, and make an informed assessment of what is really needed to maintain an adequate lawn. Research done at Penn State University as well as other places shows that properly established and managed turf on good soils can filter runoff water. While this may be true, it is also true that most lawns are not established on good soils. During the home construction process, most lots are repeatedly driven over with earthmovers, bulldozers, and trucks loaded with concrete and other building materials. After the building is completed, the compacte
