Stormwater BMPs

Question 1

Name BMPs for construction stormwater management?

Answer 1

• erosion prevention practices (planning approaches to minimize size of bare soil area and length of time disturbed, diverting location and volume of run-on, keeping concentrated flows in ditches stabilized with vegetation/rock, covering bare soil with vegetation/mulch/turf reinforcement mat/gravel/plastic sheeting)
• sediment control practices (physical filtration of sediment by trapping soil particles as water passes through a silt fence, settling processes that allow sediment to fall out of flows)
• alleviating compaction

Question 2

What are the steps for compliance at construction sites for stormwater?

Answer 2

1. Evaluate and assess the construction site
2. Select site-specific erosion, sediment, and housekeeping controls
3. Complete permitting and notification tasks
4. Construction and SWPPP implementation
5. Final stabilization and permit termination

Question 3

What is the Revised Universal Soil Loss Equation (RUSLE)?

Answer 3

An equation used worldwide to evaluate, predict, and address erosion challenges on farms, mines, and construction site. 
A = R*K*LS*C*P
A = average annual soil loss in tons/acres/year
R = rainfall-runoff erosivity factor
K = soil erodibility factor
L = length of the slope factof
S = steepness of the slop factor
C = cover management factor
P = erosion control practice factor

Question 4

What are methods of pretreatment?

Answer 4

Settling devices, screens, and vegetated filter strips

Question 5

Provide examples of non-structural stormwater BMPs.

Answer 5

Road de-icing, pollution prevention, better site design, stormwater re-use and rainwater harvesting, street sweeping for trees.

Question 6

Explain what structural stormwater BMPs are and give examples.

Answer 6

A stationary and permanent BMP that is designed, constructed, and operated to prevent or reduce the discharge of pollutants in stormwater.
Examples include green roofs, permeable pavement, tree, rain gardens, infiltration basin, infiltration trench, swales/sand filters, iron enhanced sand filter, stormwater ponds, stormwater wetlands, hydrodynamic devices, chemical treatment.

Question 7

What are the benefits of stormwater and rainwater harvest and reuse/use systems?

Answer 7

They can improve or maintain watershed hydrology, reduce pollutant loading to receiving waters, increase water conservation, reduce stress on existing infrastructure, and reduce energy consumption.