Stormwater Issues Flashcards
What are the two types of pollutants found in stormwater?
Total Suspended Solids and Phosphorus
What are sources of TSS?
pavement, vehicle exhaust emissions, vehicle parts, building and construction material, road salt/paint, pedestrian debris, soil material, plant/leaf litter, and atmospheric deposition of particles.
What does TMDL stand for?
Total Maximum Daily Loads
What should urban stormwater management focus on to control or reduce TSS concentrations?
Identifying the most important sources and then employing either specific practices to address those sources or utilize a treatment train approach.
State the hierarchy of practices for a treatment train approach to control TSS and Phosphorus concentrations.
- pollution prevention and source control (residential, municipal, and industrial)
- pre-treatment for structural BMPs (vegetated filter strips, forebays, and vegetated swales)
- infiltration (infiltration basin, bioinfiltration, permeable pavement, trees, swales with bioinfiltration base)
- settling (constructed stormwater ponds and constructed stormwater wetlands, including variants)
- filtration (green roofs, media filters, and swales)
Explain phosphorus in stormwater.
Phosphorus is essential to plant life but too much of it in water can speed up eutrophication, a reduction in dissolved oxygen in water bodies. Phosphorus in stormwater runoff is typically either fraction associated with sediment or fraction dissolved in water.
What are sources of phosphorus in urban runoff?
plant and leaf litter, soil particles, pet waste, road salt, fertilizer, atmospheric deposition of particles. Lawns and roads account for the greatest loading, contributing about 80%.
What are standards to meet Total Phosphorus water quality targets?
An antidegradation policy and implementation method. Must establish a three-tiered antidegradation program (Protection of water quality for existing uses, protection of high quality waters, outstanding national resource waters).
Why are stormwater BMPs implemented?
To protect and restore lakes/receiving waters of urban runoff.
What are issues specific to Minnesota and runoff management?
cold climate impact, mosquito control, native plants, special waters, road salt and winter maintenance, lake protection, BMPs that are pollinator friendly
What needs to be taken into account for solar farms?
The panels are impervious but the area beneath the panels is often pervious. Helpful to have vegetative surface left under the panels/between rows.
