Sustainable Stormwater Management. Michele Loudenback, RPES Stormwater Enforcement Water Quality Division Department of Environmental Quality

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1 Sustainable Stormwater Management Michele Loudenback, RPES Stormwater Enforcement Water Quality Division Department of Environmental Quality

2 Outline Urbanization and Runoff Conventional vs. Green Practices Examples of LID/GI Controls in Use

3 Some Facts 55% of U.S. streams and rivers are in poor condition 40% have excessive phosphorus levels Over 25% have excessive nitrogen levels Frequency of flooding events is increasing Increase in heavy rainfall events Increase in damages from flooding

4 In nature there are neither rewards nor punishments; there are consequences. -Robert Green Ingersoll

5 Urbanization and Runoff

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8 Urbanization and Runoff

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10 Regulatory Goal To restore and maintain the chemical, physical, and biological integrity of the nation's waters Swimmable, fishable (and drinkable) waters Create strategies that make our waters fixable

11 Conventional vs. Green

12 Conventional Practices Conventional Development Conventional Stormwater Controls High Velocity/Hungry Water Eroded Stream banks and Natural Channels Urban pollutant contaminants Impaired Water Quality

13 Green vs. Gray Infrastructure Traditional Street in OK Green Street in Washington, DC

14 LID/Green Infrastructure LID is an acronym for low impact development, an approach to land development and redevelopment that works with nature to manage stormwater as close to its source as possible. LID employs principles such as preserving and recreating natural landscape features, minimizing effective imperviousness to create functional and appealing site drainage that treats stormwater as a resource rather than a waste product.

15 If one way be better than another, that you may be sure is nature's way. -Aristotle

16 Green Practices Improved Water Quality Urban Pollutant Removal Slow velocity/sated Water Natural Stream Banks and Channels Green Development LID Stormwater Controls

17 Benefits of Green Practices Improved water quality Pollutant removal (settling, filtration, adsorption, biological uptake) Decreased cost for water treatment Decreased costly flooding events Holistic use imperative Decrease in volume and speed of runoff Restored aquatic habitat Decrease in scouring and erosion of banks and channels

18 Benefits of Green Practices Improved groundwater recharge More rainfall retained and infiltrated on site Enhanced neighborhood aesthetics Decrease in use of ugly materials Beautiful, sustainable and wildlife friendly Reduced heat island effect and improved energy efficiency Certain practices reduce heat emission and lower energy consumption

19 How Is LID/GI Implemented? Non-structural controls Don t involve physical construction Are planning and managementrelated Structural controls Involve physical construction

20 Non-Structural Controls Directed (Smart) growth Sensitive area protection Open space expansion/maintenance Waterbody buffers Impervious surface minimization Infill encouragement Green infrastructure education and incentivization

21 Incentivization Nashville, TN Reduced Stormwater User Fees Green roof rebate Reduced detention requirement Bellingham, WA Free technical assistance Expedited permit review Reduced detention requirement Reduced stormwater development fees

22 Incentivization PACE-Tulsa Voluntary Provides incentive for LID implementation through recognition Sites can be added to green tour Living Green LID program-ba Voluntary Provides incentive for LID implementation through recognition Can achieve Bronze, Silver, Gold, or Platinum LID Certification Level based on types of LID implemented

23 Development Design

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26 Structural Controls Rain Gardens/Bioretention Permeable/Pervious/Porous Materials Green Parking/Green Streets Swales Downspout disconnection Water Harvesting Techniques Green Roofs

27 Rain Gardens/Bioretention Pollutant reduction Runoff mitigation and peak flow attenuation Infiltration or underdrain Large or small drainage areas Drought-tolerant species

28 Permeable/Pervious/Porous Materials Grassed or grassless pavers, concrete, and asphalt Drain through to a storage/infiltration layer Groundwater recharge Pollutant reduction Heat island effect mitigation

29 Green Parking Combination of porous paving, reduced lot/space size, and bioretention Pollutant reduction Runoff mitigation Groundwater recharge

30 Green Streets Combination of porous paving, reduced street, and bioretention Runoff mitigation Pollutant Reduction Groundwater recharge

31 Swales Peak flow reduction Pollutant removal (can be enhanced with check dams) Increased infiltration Cost effective

32 Downspout Disconnection Peak flow reduction Increased infiltration Increased aesthetics Cost effective

33 Rain Harvesting Complicated by water rights laws in some states Runoff mitigation Reuse

34 Green Roofs Peak flow reduction Urban heat island effect reduction Drought-tolerant plants appropriate Can be used to support habitat Difficult to retrofit structures

35 Pictures

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51 Activity

52 Questions, Comments, Discussion Rain is grace; rain is the sky descending to the earth; without rain, there would be no life. -John Updike

53 WQD Stormwater Contacts Permitting Michael Jordan - (405) Karen Milford (South) - (405) Ismat Esrar (North) - (405) Compliance/Enforcement Wayne T. Craney - (405) Michele Loudenback (East) - (405) Michelle Chao (West) - (405)