Hillside Runoff Erosion

Hillside Runoff Erosion
Lick Run Trib

Stormwater Problems

Removal of natural woodlands and replacing it with impervious (nonpourous) surfaces including roads, rooftops and parking lots changes pre-development drainage patterns by increasing the quantity of runoff from a site. Runoff from these sites can carry significant quantities of pollutants, including sediment, fertilizers, oil, litter, animal wastes, heavy metals and pesticides. In summer months, runoff from heated roads and parking lots can cause a rapid increase in stream temperature and cause fish kills. In winter, salt and sand used to remove snow from roads also contaminates streams.

Increased runoff enters streams directly instead of replenishing the groundwater supply. This decrease in groundwater often leads to lower flow levels within our streams during dry periods. This can be detrimental to fish and other stream organisms.

Many of the sewer systems within the watershed are combined sewer systems. They carry both sewage and stormwater. These systems are designed to overflow at designated locations into the streams of the watershed to protect sewage plants during heavy rain events. But some of these outfalls begin to overflow during rainfall events of 1/4 inch or less. This raw sewage and stormwater mix compromises water quality and creates potentially unhealthful situations. Many municipalities within the watershed are currently under a consent decree agreement to reduce these combined sewer overflows.