Highway construction within the Olentangy River flood plain in Columbus, Ohio, was projected to be a large source of suspended sediment to the river system. A monitoring program was begun by the U.S. Geological Survey in 1978 to quantify the implacts of construction process. Sediment information was collected daily at six gaging stations located above, below, and within the construction area. Yields of suspended sediment from the active construction area ranged from 9,580 to 15,700 tons per square mile per year. Surrounding suburban terrain yielded 428 to754 tons per square mile per year. However, the size of the construction project was small in comparison to the surrounding suburbs contributing sediment. No more than 4 percent of the yearly downstream suspended-sediment loads were produced by high-way construction during the monitoring periods.