Construction Site Storm Water Runoff

Polluted storm water runoff from construction sites often flows to storm sewers and ultimately is discharged into local rivers and streams. Of the pollutants typically in storm water runoff, sediment is usually the main pollutant of concern. Sediment runoff rates from construction sites are typically 10 to 20 times greater than those of agricultural lands, and 1,000 to 2,000 times greater than those of forest lands.

During a short period of time, construction sites can contribute more sediment to streams than can be deposited naturally during several decades. The resulting situation, and the contribution of other pollutants from construction sites, can cause physical, chemical, and biological harm to our waters.

Caddo has implemented a permitting program consistent with state and federal programs for control of pollutants in storm water discharge from construction sites. Caddo’s program is no more stringent, but our efforts to reinforce the existing federal and state programs will further the reduction in pollutants in the storm water discharged to our waters.

Our main effort is to ensure compliance with existing state programs (Louisiana Pollutant Discharge Elimination System) by not facilitating any construction projects that are not complying with state and federal regulation. To do this, Caddo will ensure that all projects are properly permitted prior to issuance of development permits. This will be accomplished through the development and implementation of a construction site runoff ordinance, erosion and pollution control guidance, and construction site inspection to ensure compliance.

There are two programs for permitting storm water discharges from construction activities:

• Small Construction (1-5 acres disturbed area)
• Construction (5 or more acres disturbed area)

Both programs are currently administered by the Louisiana Department of Environmental Quality.