Water Quality and Flow Monitoring

The area that makes up CRWD is highly urbanized: 42% of CRWD is impervious surface. All the roads, streets, roofs, and parking lots prevent water from soaking into the ground, and so it is directed with great speed to storm drains that direct water to our lakes, streams, and wetlands. In CRWD, eventually all runoff drains to the Mississippi River. CRWD also includes four major lakes: Como, McCarrons, Loeb and Crosby.

To evaluate CRWD’s water quality, CRWD established a monitoring program in 2004 to collect stormwater data from the major subwatersheds in CRWD and stormwater best management practices (BMPs), which was then largely unavailable. The goals of CRWD monitoring program are to:

assess the quality of stormwater runoff and compare to water quality standards,
evaluate effectiveness of stormwater BMP programs,
identify water quality problem areas,
calibrate computer models and
determine water quality trends.

Monitoring stormwater also helps CRWD track the quantity of pollutants being discharged from different geographic areas in CRWD.

Monitoring Sites
Currently, CRWD’s monitoring program operates a variety of monitoring sites throughout the watershed. These monitoring sites include:
full water quality stations,
flow only stations,
level only stations,
peak level monitoring sites
precipitation monitoring sites, and
lake monitoring sites.

To view a map of monitoring sites, click here.

Monitoring Results
Stormwater runoff is the most significant source of water pollution in CRWD. It carries and delivers fertilizers, pesticides, pet and wildlife waste, trash, and other pollutants through the storm sewers that drain to the Mississippi River. The pollutants of most concern in CRWD include phosphorous, sediment, metals such as lead and zinc, and bacteria. Stormwater pollutants in CRWD are typical of pollutants found in other urbanized areas throughout the country.

For detailed results of CRWD’s monitoring programs, click here to be directed to our Reports page.

For results on performance of stormwater BMPs, click here.