Urban runoff

Studying urban runoff.

PCBs in urban-runoff sediments, an indication of active contamination sources.NGU has studied for many years the content of different pollutants, such as PCBs, PAHs, TBT and heavy metals, in urban soil and related products.

In the project Urban Risk we are studying the significance an urban area may have on the occurrence and dispersion mechanisms of pollutants to an adjacent marine environment.

Impervious surfaces

Urban areas may consist of up to 100% impervious surfaces, such as asphalt roads, parking lots, and roofs. The impervious surfaces may cause a strong runoff, leading the storm water either into a sewage system or directly into the sea.

If the predictions for Norway come true of increased amounts of precipitation and more intense storms in the years to come, the runoff from urban areas and the dispersion of pollutants could cause severe environmental problems for the marine environment.

Dietary advices

NGU has shown that active dispersion of pollutants is taking place in Bergen, which is one of 31 locations in Norway with unacceptable high concentrations of different pollutants in marine sediments. This kind of environmental challenge has lead to dietary advices on the consumption of seafood from these areas.

Studies of active contamination sources and the consequent dispersion of pollutants to adjacent harbors are important for environmental authorities when selecting different remediation solutions, such as dredging or covering.