Storm Water 101

"Storm water" is surface runoff generated from rain and melting snow that flows over land instead of infiltrating into the ground. It is most readily observed as the by-product of urban growth where vast amounts of impervious land cover exists (i.e. paved streets, parking lots, driveways, building rooftops, etc.). The Fairbanks area has a storm drain system that conveys this surface water runoff away from public street rights-of-way and commercial and residential properties to nearby water bodies. The system is comprised of over a thousand culverts and storm drain inlets, hundreds of miles of ditches and buried storm drain pipe, and over a hundred outfalls that serve as discharge points to nearby water bodies.

Flooding street
Storm Drain
Water at a culvert

As runoff travels over developed land surfaces, it accumulates a variety of pollutants (such as those shown in the following figure) that are transported by the storm drain system to local water bodies without treatment. The results can significantly alter our natural environment by contaminating drinking water supplies, making recreational areas unsafe and unpleasant, harming fish and wildlife populations, and impairing native vegetation.

Variety of Pollutants That Can Enter the Local Water Bodies

At the outfall, the pollutants collected in storm water can be readily seen discharging to local water bodies.

Garbage at a culvert
Water flooding at culvert