Effects of roadway and pond construction on sediment yield near Harrisburg, Pennsylvania

This report shows the effects that the construction of half a mile of one-lane roadway during June, July, and August 1970 and construction of a 5-acre pond during August and September 1970, had on sediment concentrations and sediment discharge of a stream draining an area of 0.76 square mile. The effects of the construction are shown by comparing the data collected from the affected basin with data collected from a similar adjacent basin, unaffected by construction.

During the pond construction, base-flow sediment concentrations increased from the expected 6 mg/1 (milligrams per liter) to an average of 35 mg/l. Sediment discharge during June through December 1970 attributable to the construction was 55 tons, two-thirds of the amount normally expected during a year.