How urban runoff impacts our lives.
Our water and its vitality are the most simple
Open field
Forrest, grasslands and wetlands trap rainwater, allowing it to naturally percolate and filter back into ground.
form of our communities sustaining a healthy and economically viable lifestyle.
In the very early 1900s, most urban areas and municipalities across the nation built sewer systems to carry rainwater and sewage in the same pipe. This is called a combined sewer system. During dry weather conditions, the sewer system works fine. But, during heavy rainstorms, these combined flows frequently exceed the capacity of the sewer system and contaminants overflow into various waterways, causing a variety of environmental concerns. This is typically referred to as combined sewer overflow or CSO. large paved parking lots
When we pave and develop impervious hardscapes we take away the ability of rainwater to naturally filter back into the earth.
For more than 30 years, urban runoff has been recognized by almost every municipality as a significant detriment to the health and vitality of their geographical regions. Both stormwater and CSO discharges cause physical, chemical, biological and combined effects on receiving waters, seriously impairing beneficial water uses in most locations. In newer urban areas, some mitigation of flooding and erosion impacts have been achieved by certain stormwater management practices, but progress has been relatively slow because of high costs of retrofits or new systems. The current system is not working, nor will it be able to sustain our needs as urban areas become more densely populated. We need to find a better way to manage urban runoff.