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Polluted Runoff: Nonpoint Source (NPS) Pollution

Nonpoint Source: Roads Highways and Bridges

Runoff controls are essential to preventing polluted runoff from roads, highways and bridges from reaching surface waters. Erosion during and after Freeway with heavy trafficRunoff-control measures can be installed at the time of road, highway and bridge construction to reduce runoff pollution during and after construction.construction of roads, highways and bridges result in the deposition of sediment that can smother aquatic habitat and clog waterways.  

Heavy metals, oils, other toxic substances and debris from construction traffic and spillage can be absorbed by soil at construction sites and carried with runoff water to lakes, rivers and bays.

Runoff control measures can be installed at the time of road, highway and bridge construction to reduce runoff pollution both during and after construction. Such measures can effectively reduce the entry of pollutants into surface waters and ground waters and protect their quality, fish habitats and public health. Pesticides and fertilizers used along roadway rights-of-way and adjoining land can pollute surface waters and ground water when they filter into the soil or are blown by wind from the area where they are applied.