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What is Stormwater?


Stormwater is rain or melting snow that does not infiltrate into the ground. As stormwater travels across lawns, parking lots, gardens, roofs, and roadways, it can pick up pollutants like trash, gasoline, motor oil, fertilizer or pesticides, and bacteria from pet waste. The polluted water can enter the stormdrains and flow untreated to the Boise River. These factors impair water quality and degrade our river’s condition.

Stormwater Protection

With continued population growth and changing land use, the expansion of urban areas is creating more impervious surfaces, such as roofs, roads, and parking lots that prevent the stormwater from infiltrating into the ground. This increases the pollutant load that reaches the Boise River during rain and snowmelt events. Stormwater runoff is an increasing source of water pollution across the United States and can have impacts on water quality.

The City of Boise is using Green Stormwater Infrastructure (GSI) as a sustainable approach to managing urban stormwater impact that delivers environmental, social, and economic benefits.  GSI solutions include permeable pavement, green roofs, bioswales, and underground filtration beds to absorb and cleanse stormwater on-site, at the source.


The Partners for Clean Water have developed a Green Stormwater Infrastructure Tour to highlight implementation of GSI practices in the Lower Boise River Watershed. The tour is accessible online and interested parties can also visit the sites in person to view the GSI installations.