Case Histories

Near Larkspur in Douglas County an access road and shallow borrow ditch were cut to serve an airport runway uphill from the access road. During construction of the road and borrow pit a large area was stripped of vegetation. Heavy water runoff from above the runway and the runway itself was channeled down the borrow ditch. There were no control features to slow the velocity of the water or retard erosion. Within five years the borrow ditch was eight feet deep. Properly designed and installed water control structures, revegetation of the graded area, detention ponds, drop structures, and other measures would have paid for themselves in later maintenance and repair costs.