Stormwater runoff is water from rain or snowmelt that comes off of roofs, driveways, sidewalks, and other surfaces that does not infiltrate into the ground.
When stormwater flows over surfaces, it picks up and carries pollutants on those surfaces becoming polluted. Common stormwater pollutants include oil, sediment, pesticides, fertilizers, litter, yard waste, and pet waste.
Every day activities we do around our businesses, homes, and yards can impact the quality of our stormwater. Some common examples include over fertilizing our yards or fertilizing before a heavy rain, not picking up pet waste, and excessive use of pesticides. Oil drips from vehicles, litter, yard debris, and sediment are other examples of common stormwater pollutants.
Managing our stormwater aims to improve the quality and reduce the volume of stormwater. Unlike sanitary sewer water, stormwater does not receive any treatment before it enters our waterways, thus delivering pollutants with it that it picks up along the way. This adversely affects wildlife, human health and safety. In addition, water that falls on hard surfaces and doesn't infiltrate into the ground runs off to lower areas, with excess runoff potentially causing local flooding and stream bank erosion.
The Environmental Protection Agency (EPA) regulates stormwater discharge through the National Pollutant Discharge Elimination System (NPDES) program. The City of Cedar Rapids is required to comply with NPDES regulations for its Municipal Separate Storm Sewer System (MS4) (view permit here), and implements a stormwatermanagement program that includes 6 minimum control measures that include:
1.Public Education and Outreach on stormwater impacts
2.Public Involvement and Participation
3.Illicit discharge detection and elimination
4.Construction site stormwater runoff control
5.Post-Construction stormwater management
6.Pollution prevention/good housekeeping for municipal operations
The stormwater utility fee is used to cover the cost of maintaining and making needed improvements to the storm sewer system that includes over 300 miles of stormwater piping, 15,000 stormwater intake structures, and 38 stormwater detention facilities. It also includes flood response, construction site inspections, and street sweeping, helping to protect and improve the quality of our local streams. Stormwater Utility Improvement Program.
When working around you home or yard, make sure you dispose of products properly, never dump or dispose of items in storm drains, pick up after your pets, keep yard waste out of the street, and eliminate or minimize the use of fertilizers and pesticides. Volunteer to help educate your community on how they can help prevent stormwater pollution.
An illicit discharge is any discharge to the MS4 that is not composed entirely of stormwater. These may occur due to illegal connections to the storm drain system in which wastewater enters the storm drains (i.e. floor drains connected to the storm drain system). Direct dumping of waste into a storm drain or placement such that waste can enter the storm drain system is also a form of illicit discharge.
Stormwater Words and Terms
process in which contaminants and sediment are removed from stormwater runoff by collecting stormwater into a ponding area consisting of a grass buffer strip, sand bed, organic layer, soil, and plants.
A shallow vegetated depression that collects and conveys stormwater runoff. A stormwater BMP, a bioswale reduces runoff velocity allowing for infiltration and treatment.
An excavated area used to manage stormwater runoff by temporarily storing stormwater, reducing the peak rate of runoff to a stream or storm sewer.
a topographic region in which all water drains to a common area.
Process in which soil and rock are worn away or removed from a surface by the action of waterflow, wind, or ice.
Iowa Department of Natural Resources. State agency that writes and enforces regulations for conserving and enhancing natural resources of the State of Iowa.
Any discharge to the municipal separate storm sewer system that is not composed entirely of stormwater.
Municipal Seperate Storm Sewer System. A municipal conveyance system that collects and conveys stormwater that is not combined with the sewer system.
National Pollutant Discharge Elimination System. The part of the Clean Water Act which requires point source discharges to obtain permits. NPDES permits are administered by the Iowa Department of Natural Resources.
A shallow planted depression with adapted or deep-rooted native plants and grasses, that collects rainwater runoff to infiltrate into the ground.
A large depression used to manage stormwater runoff to prevent flooding and downstream erosion, as well as improve water quality by settling and filtering pollutants. Unlike detention basins that temporarily hold water, retention ponds are designed to hold a specific amount of water indefinitely.
The flow of water from rain or snow over land that does not infiltrate into the ground.
A structure that collects excess rain and ground water from paved streets, parking lots, sidewalks, and roofs.
Water from rain events that runs off of roofs, driveways, parking lots, yards, and other surfaces that does not infiltrate into the ground.
Best available practice or device that helps to control, treat, or prevent stormwater runoff pollution.
Pipe systems, culverts, open channels, and bridges that collect and transport stormwater to oufalls and receiving waters.
Methods for collection and conveyance of stormwater runoff that minimize the impacts development on the hydrology and water qaulity of local waterways.
United States Environmental Protection Agency. A federal government agency that writes and enforces regulations based on laws passed by Congress for the purpose of protecting human health and the environment.