Runoff from construction sites is widely regarded as one of the leading causes of water pollution nationwide. Stormwater runoff is rain water that flows over the ground, sometimes with extreme force, which carries dirt, debris and chemicals into our waterways, endangering the health of our communities and environment. Sediment runoff is the number one pollutant of waterways in Alabama, accounting for roughly 20% of Alabama’s impaired streams. The number may actually be higher because so few of Alabama’s waters are monitored adequately for pollutants.