Stormwater Runoff
Stormwater runoff is rain or snowmelt that runs off of streets, parking lots, lawns, and other surfaces and into drains that flow directly into local waterways. Untreated stormwater carries pollutants such as fertilizer from lawns, pesticides, oil and anti-freeze, animal waste, and sediment, all of which can compromise the integrity of a watershed. These pollutants are known as non-point source pollution When pollution enters the waterway, it can cause algae blooms, loss of habitat or species, and significant human and animal health risk. Water that enters a storm sewer system is discharged untreated unto the waterbodies we use for swimming, fishing and drinking.
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Polluted stormwater runoff can have many adverse effects on our ecosystems, and the plants, fish, animals and people that populate them.
- Erosion
- Sediment Transport
- Flash Flooding
- Direct surface pollution loading (motor oil, fertilizers, pet waste, road salt)
Low Impact Development
RAIN BARRELS
Although rain barrels are one of the most fun BMPs around, they aren’t necessarily the most effective. Each rain barrel has a small relative storage capacity and inconsistent drainage. Even if every home in the Kiefer Creek Watershed had 5 rain barrels that were empty, they would only be able to capture half of the runoff from residential roofs, which only make up XX percent of the total impervious surface area in the watershed.
That being said, the implementation of rain barrels can be optimized to target key runoff areas, such as the front downspouts suburban homes. In an optimized model for the Kiefer Creek area, outreach should be focused on the the areas of the watershed that are doing the most damage due to flash flooding and erosion. Rain barrels can be paired with tree plantings, rain gardens, and gardening to help keep new plantings, hydrophilic vegetation or lawns consistently watered, drip hoses with the right perforation size can be perfect for this application. By reducing use of potable water in the lawn and garden we reduce the amount of water withdrawn from the Meramec River, which reduces the concentration of pollutants in the river, restores natural flow, and reduces infrastructure wear and tear.
Although rain barrels are one of the most fun BMPs around, they aren’t necessarily the most effective. Each rain barrel has a small relative storage capacity and inconsistent drainage. Even if every home in the Kiefer Creek Watershed had 5 rain barrels that were empty, they would only be able to capture half of the runoff from residential roofs, which only make up XX percent of the total impervious surface area in the watershed.
That being said, the implementation of rain barrels can be optimized to target key runoff areas, such as the front downspouts suburban homes. In an optimized model for the Kiefer Creek area, outreach should be focused on the the areas of the watershed that are doing the most damage due to flash flooding and erosion. Rain barrels can be paired with tree plantings, rain gardens, and gardening to help keep new plantings, hydrophilic vegetation or lawns consistently watered, drip hoses with the right perforation size can be perfect for this application. By reducing use of potable water in the lawn and garden we reduce the amount of water withdrawn from the Meramec River, which reduces the concentration of pollutants in the river, restores natural flow, and reduces infrastructure wear and tear.
REDUCING UNNECCESSARY IMPERVIOUS SURFACES
Paved surfaces contribute to stormwater runoff by preventing water from soaking into the ground naturally. Therefore, paved areas that are not in constant use, including overflow parking lots, islands, and areas with long term vacancies could potentially be converted back to natural ground. De-paving surfaces also increases land available for trees and habitat.
Additionally, permeable paving is one of the best ways to address runoff from roadways. System such as grasspave or gravelpave, which are less intensive than normal paving, would help reduce both chloride and bacteria loading into Kiefer Creek with effective design. The expense of the system can vary a lot depending on the type of paver or structural component employed and depth and sieve size of the unlying aggregate base. The impact of permeable pavers can be increased by excavating sump areas that can store larger volumes of water under the pavers and by selecting the best sites for permeable pavers based on impervious surface catchment drainage and stormwater inlet locations. |
CURB PERFORATION & TRENCH DRAINS
Curbs keep runoff on the roadways until it enters the stormwater system, preventing filtration and infiltration while increasing runoff volumes. Creating breaks in the curb where stormwater can pass through to planters can reduce the flow of stormwater that reaches the drain, and later, the creek.
Trench drains carry runoff through a channel to a specific area such as a garden or planter where it can be absorbed more slowly and filtered before it reaches a storm drain or the creek.
Curbs keep runoff on the roadways until it enters the stormwater system, preventing filtration and infiltration while increasing runoff volumes. Creating breaks in the curb where stormwater can pass through to planters can reduce the flow of stormwater that reaches the drain, and later, the creek.
Trench drains carry runoff through a channel to a specific area such as a garden or planter where it can be absorbed more slowly and filtered before it reaches a storm drain or the creek.
GREEN ROOFS
The term Green Roof typically refers to any built structure whose roof is covered or partially covered with vegetation. The vegetation is often layered with various insulators and drainage layers, and appears to be a lawn on top of a building. Green roofs have been shown to both reduce the volume and speed of runoff, which in turn reduces runoff entering the stormwater drain system and the creek. Green roofs can also help reduce erosion, filter the water that does drain, reduce the urban heat island effect, improve insulation within a building, and improve air quality among other things.