Whenever a storm strikes it comes with a huge amount of storm water which takes the form of runoff. When this runoff is generated it flows over the land or impervious surfaces (paved streets, parking lots, and building rooftops), it accumulates debris, chemicals, sediment or other pollutants that could adversely affect water quality if the runoff is discharged untreated. To control this run off a storm water system is required to be implemented.

Storm water systems harness the storm water and stream it into storm water drainage system which includes catch basins, storm sewers, creeks, ponds, lakes, lift stations, force mains, ditches, natural low areas and drainage features to accommodate storm water run-off. A storm water system formalizes and constructs these facilities as necessary to accommodate run-off from areas as they develop. This storm water system not only streamlines the storm water but also accommodates water originating within a specific area, and the water originating from other adjacent areas.

In addition to accommodating the quantity of storm water run-off, the storm water system also serves an important water quality function. The storm water systems, depending upon its design and operation, can remove significant amounts of natural and man-made pollutants from the storm water, like storm water treatment ponds, sedimentation sumps within manholes, erosion control practices, and street sweeping programs. It is prohibited for any resident to alter any aspect of a storm water pond as this may lead to the improper functioning of the pond.

There are many tools like end of pipe traps, storm water booms, spider walking excavators and multi-purpose dredges being used for treatment of Stormwater runoff. There are like booms that are designed to trap large volumes of floating gross pollutants in open waterways, including canals, creeks and rivers. The booms are effective on various kinds of pollutants, such as, trash, silt, weeds and oil. There are new silt barrier booms available to deal with the silt and sediment from upstream sources. One of the s called the "spider" excavator may be used to remove silt and heavier rubbish.

If a storm water bmp is not used and instead an individual practice is used then it may not be effective, but once combined with a good system it may provide a key function in highly effective systems. Per the Phase II rule, such system-building requires stating the minimum requirements in general terms. This allows the use of the most appropriate set of practices that could be used during specific situations to achieve the minimum measures.