Site Erosion Control

Written by Gary Bock, Project Manager, Vancouver Watersheds Council.

Sediment is one of the most common pollutants in Clark County’s rivers and lakes. It is most often washed off construction sites or roads and can smother both plant and animal life in a stream or wetland. Erosion control is important even on small-scale land clearing projects. Fortunately, erosion control is fairly simple on small lots without much slope. First, try and maintain as much of the existing vegetation as you can. Virtually all plants are valuable for erosion control and even simple grass can hold a gentle slope in place. When you must strip vegetation, cover the exposed dirt as soon as possible with mulch, straw, compost, or gravel. If you have a pile of topsoil or mulch, cover it with plastic. If there will be trucks coming in and out of your construction project, be sure and provide a construction entrance. This entrance should include four to six inch diameter rock on top of a geo textile material. This will knock mud and dirt off the tires of the trucks and prevent sediment from collecting on the street and being washed into the storm drain.

Storm drains and roadside ditches lead directly to streams and wetlands, usually without any treatment to improve water quality. Dirt, mortar, concrete, or paint will eventually wash into streams or wetlands if dumped on the ground. Even construction materials and debris left out in the rain can leach pollutants into surface or groundwater.

June 25th, 2007