Many of the impairments Plaster Creek faces are caused by stormwater--rain or snowmelt that runs over land instead of soaking into the soil. For an overview of stormwater, visit Fifteen to the River, a collaborative project by the West Michigan Environmental Action Council, the City of Grand Rapids, and other partners. Or, watch our short slideshow to learn how stormwater affects Plaster Creek in particular.
Here are the pollutants identified in the Plaster Creek Watershed Management Plan.
- Sediment: Stormwater runoff causes flooding in Plaster Creek, which erodes stream banks and washes sediment into the creek. Sediment can also be introduced into the stream by runoff from agriculture and construction sites. Overabundant sediment in the creek blankets the creekbed and destroys habitat for fish and other aquatic life. It is also carried into the Grand River and Lake Michigan.
- E. coli contamination: We know that E. coli contamination is a problem in Plaster Creek, but we don't know how exactly it gets there. Possible sources include dumping pet-waste down storm drains, leaky septic tanks, agricultural sources (livestock, manure), waste from wild animals, and many others. The sources of E. coli are not well understood, but it's clear that stormwater runoff from all parts of the watershed - both urban and rural and everything in between - is making the E. coli problem worse.
- Nutrient pollution: Excess nutrients from lawn fertilizers, agricultural outputs, and animal manure can cause algae to bloom, compromising stream quality and degrading ecosystems downstream.
- Thermal pollution: Runoff from warm, paved surfaces causes creek temperatures to fluctuate dramatically, making it inhospitable for native fish and other aquatic wildlife.
- Toxic substances: The creek is contaminated by untreated urban runoff, road salt, and pesticides. Old industrial sites in the watershed may also be leaching legacy pollutants into the stream.