WATERSHED AUDITS Auditing Stormwater Best Management Practices (BMPs) This Presentation Posted At ceds.org/audit

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1 WATERSHED AUDITS Auditing Stormwater Best Management Practices (BMPs) This Presentation Posted At ceds.org/audit 1

2 No Need To Take Notes Download these publication at: ceds.org/audit

3 Why You Are Critical To Keeping BMPs Working Used To Be Inspect Every 3 Years Future: Annual Inspection Used To Be 2-3 BMPs Per Site Future: Per Site There s simply no way government inspectors alone can keep all these BMPs working.

4 Presentation Topics 1. How Development Harms Aquatic Resources 2. Stormwater Management Evolution 3. Finding BMPs in Your Watershed 4. Evaluating BMPs For Maintenance Needs 5. Getting BMPs Quickly Fixed

5 Topic 1: How Watershed Development Harms Aquatic Resources Forest loss; Physical aquatic habitat impact; Accelerated channel erosion; Increased pollution loads; and Reduced groundwater inflow.

6 What Is A Watershed? All that land draining to a water body or a given point on a waterway. Chesapeake Bay watershed 64,000 square miles A watershed is defined by hilltops, ridgelines and other high points that cause storm runoff or groundwater to flow to a specific waterway.

7 Groundwater Recharge Provides Dry-Weather Inflow Lack of recharge causes streamswetland to dry Arrow size shows magnitude of change

8 Forest = Highest Recharge + Cleanest Inflow + Least Flooding = Healthiest Waters

9 Physical Damage To Aquatic Habitat

10 Accelerated Channel Erosion Converting a forest watershed to four homes per acre can increase flooding 100-fold

11 Increased Pollution Loads Vehicle Exhaust Pet Waste Impervious surfaces cause pollutants which once soaked into forest soils to runoff Coal-Fired Power Plant & Other Industrial Emissions Lawn Care Chemicals

12 Net Effects of Watershed Development Impervious Area & Aquatic Resource Health Sensitive Resource Brook Trout Wetland Percent Impervious Area Threshold 2% 4% Acres Per House 10 8 Tidal Waters Other Waters Safe for Children Waterway Dies 5% 8% 15% 25%

13 Topic 2: Stormwater Management Evolution Period Early 1900s Post WWII 1960s 1970s 1980s 1990s Dry Ponds Approach Combined Sewers Catch Basins Regional Ponds End of Pipe Infiltration First; But mostly ponds High Failure Rate Offline Filters End of Pipe Ponds Environmental Site Design Purpose Public Health Trash-Sediment Flood control Flooding; Control of Channel Erosion & Pollutants Plus Groundwater Recharge Diffuse BMPs; Protect Sensitive Areas

14 Combined Sewers & Catch Basins + Minimal Pollutant Retention =

15 s Dry Ponds/Regional Facilities Dry Pond Serving Single Site Regional Ponds Briefly Popular But Left Long Stretches of Stream Channel Unprotected Stand-Alone In-Stream Projects Have Similar Shortcomings

16 s 90s Conventional End-Of Of-Pipe Structures Storm Drain Inlet 20% Pollutant Removal Storm Drain Outfall No Groundwater Recharge

17 s 90s Infiltration Basins & Trenches One of Few Functioning Infiltration Basins Typical SHA Infiltration Trench An Infiltration Basin With Cattails No Longer Infiltrating; One Of Many

18 2000 Maryland Stormwater Design Manual Offline Filters: Higher Pollutant Removal, Better Channel Protection tion & Groundwater Recharge Flow-Splitter Allows 90% of Runoff To Enter Water Quality BMPs; But Not Scouring Flows WQ v = Water Quality Volume Re v = Recharge Volume Cp v = Channel Protection Volume

19 2007 Environmental Site Design Principles Clear the smallest area of vegetation; Avoid steep, highly-erodible soils; Direct runoff away from exposed soil; Quickly apply mulch-grass seed to disturbed soils; Protect aquatic buffers and other sensitive areas; Minimize impervious area; All impervious areas must drain to ESD practices; Increase aquatic buffers and forest.

20 Environmental Site Design BMPs Diffuse Throughout Site To Mimic Natural Recharge; Small Drainage Area Reduces Failure; and Mulched Surface Increases Pollutant Removal-Reduces Reduces Failure Permeable Pavers Green Roof? Bioretention/Rain Garden Dry Swale

21 Redevelopment Definition Existing Site Impervious Area (IA) Greater Than 40% Reduce IA By 50% or Treat With Highly- Effective BMPs Critical For Restoring Degraded Suburban- Urban Waters

22 In-Channel BMPs Essential To Healthy Ecosystem But Not A Panacea Upland BMPs Critical To Success; In-Channel = 2-5% 2 N Removal vs. 70% Spring Branch: Doing Well Wilenor: A Great Project! Central Sanitation Regenerative Stream Restoration: Lower Third Blew Out

23 Topic 3: Finding Stormwater BMPs Search Along the Downslope Edge of Each Community-Commercial Commercial Area Older BMPs Mostly At Downhill Edge of Development Road High Point inlet inlet Storm Drain Outfall Side View SWM Pond Pond Storm Drain Inlet New BMPs Within Development Storm Drain Outfall

24 Maryland StormwaterPrint To view BMPs click 1. Your county-city city 2. More then 3. BMP then watershed 4. Aerial 5. Zoom to your area StormwaterPrint Opening Window CAUTION: Balto Co & City data very inaccurate! Wet pond Bioretention Infiltration trench

25 Topic 4: Evaluating BMPs 35,000+ Existing Maryland Stormwater BMPs Sand Filter Permeable Pavers Bioretention/Rain Garden Wet Swale Moderately Effective = 35-55% Nutrient Removal; No Runoff Volume Reduction; No Recharge Highly Effective = 70% Nutrient Removal; Runoff Volume Reduction; Provides Recharge Wet Extended Detention Wet Extended Detention Infiltration Trench Green Roof? Constructed Wetland Dry Swale Wet Pond Infiltration Basin Moderately-Effective BMPs Highly-Effective BMPs

26 Three Stormwater BMP Types PONDS INFILTRATION BIORETENTION/SWALE Wet Pond Bioretention Retains Pool of Water Dry Ponds Infiltration Trench Observation Well Usually Present Infiltration Basin 6-12 Surface Depression Mulch; Observation Well Dry Swale Drains Completely; Outlet at Bottom Outlet 1-2 Feet Above Bottom Wide, Gently Sloping Bottom; Observation Well

27 Trespassing Not Required Most BMPs Can Be Evaluated from Nearby Public Areas Trespassing Gives Polluter Easy Out; Lessens Your Credibility; UnethicalU View from street Search for Better Access Wet Pond View BMP From Adjoining Streets, Parking Lots & Other Public Areas Don t walk through yards Bioretention Clogged-Failed Bioretention View facility from adjoining public streets or parking areas.

28 Ponds What To Look For Contact owner-agency if <half of original storage remains New Extended-Detention Wet Pond Good (Full) Pollutant Storage Partial storage Over time sediment accumulates, cattails encroach and pollutant storage is lost Zero storage Eventually, pollutant storage-removal drops to zero

29 Why Pond Volume Is Critical When wet pool volume declines to less than half, removal drops dramaticallyd

30 Pond Failure Issues Report Any Of These Issues to County-City City Agency Excavated Pond Top of embankment straight, level; no settlement Low-spots may become overflow, failure area Embankment Before Excavation Embankment Ponds Vulnerable to Failure-Washout Larger ponds have emergency spillway Embankment Pond After Excavation Trees on embankment Wetlands plants on embankment Burrows

31 Observation Well Stone trench enhancing infiltration Outlet 1-2 Feet Above Floor Failed Infiltration Basin - Full of Cattails Infiltration Basin 80% - 95% Pollutant Removal Is it infiltration: Lowest opening foot above pond bottom Observation well usually present Water Quality volume = First inch IA runoff WQv rainfall occurs monthly Must drain in hours Check after -11 inch rainfall No wetland vegetation No exposed soil in drainage area

32 Infiltration Trench & Dry Swales 80% - 95% Pollutant Removal Does trench store one-inch runoff without overflow? Does most runoff infiltrate before reaching end of swale? Observation well drains completely in 48 hrs? Most roadside grassed channels are NOT infiltrating swales

33 Bioretention Settings 5% of Existing BMPs; Our Most Effective BMP?; Most Common Future BMP Commercial - Mulched Residential - Mulched Commercial - Grass Commercial - Stone

34 Bioretention Evaluation Minimum 6-inch 6 storage; Mulch; Permeability 6-inch minimum storage Bioretention Must drain in 48 hours Maryland Stormwater Design Manual Cattails & other wetland vegetation indicates failure Two inches of mulch Observation well dry after 48 hours since runoff ended Use stick to see if hole goes all the way through

35 Exposed Soil Kills BMPs Disturbed soil draining to BMPs should be immediately stabilized Cover soil with tarp Apply soil binder along with grass seed and fertilizer Apply 2 tons mulch per acre; Enough that soil can t be seen

36 Does a BMP Have Adequate Capacity? Rain Gage & Float Method Rain Gage Float INSTRUCTIONS 1. When rain of a half inch or more is predicted, place p the rain gage next to the BMP. 2. Place an object that floats, like a stick, where runoff would first overflow from the BMP (inlet lip). 3. Tie the float string to a fixed object so the float doesn t wash away. 4. Check the float and gage after storm. 5. If the float washed down the inlet with less than an inch of rain in 24 hrs, then the BMP needs cleaning.

37 Alert BMP Owner If (or refer to enforcement agency) Zero storage Rain Garden/Bioretention <6 storage; <2 mulch Wet pond or extended-detention-wet yet no wet pool storage area remains BMP is infiltration measure (observation well present) and wetland vegetation present or BMP holds water >48 hrs > rain You find low-spots, animal burrows, wetland plants or trees on embankment Monitoring Well 6

38 Topic 5: Getting Problems Solved Imminent Threat Pond Failure Issue Not So Imminent Pond has no pollutant storage capacity or infiltration basin full of cattails Imminent Pollution Report immediately Not So Imminent Identify responsible party (aka polluter) Make neighborly request to correct If no action report to enforcement agency

39 Reporting Imminent Problems in Maryland ceds.org/audit For all other problems call the Maryland Department of the Environment (MDE) at: Main Number: After Hours: Eastern Shore: Western Maryland:

40 Cooperation First: Pollution Not So Imminent Send Letter to Responsible Party (aka polluter) Gets 50% of Problems Fixed; Usually Faster Then Referral to Enforcement Agency; Makes Friends, Not Enemies This Sample Letter Is In Your Folder Neighborly tone Respectful Describe your interest Say you normally file complaint, but this letter more neighborly, respectful List assistance sources Offer to help Provide your contact info

41 Identifying Responsible Parties IDENTIFYING PROPERTY OWNERS Go to the Maryland Environmental Land Resources Information (MERLIN) website: Zoom in on the BMP location. Check the Parcel Boundaries box. Click the Identify button. Click on the Parcel containing the BMP. Click on the little orange-red triangle and a Property Record, like that to the lower left, will appear. Send correspondence to the Owner at their mailing address, not the premises address. Use MERLIN parcel layer to get Property Record

42 Cooperation First Steps Not Fixed Send Letter Problem Fixed Thank You Letter Phone Call Cooperative But Not Fixed Uncooperative Problem Fixed Thank You Letter Tour Contact Tenants Residents Refer To Enforcement Thank You or Refer To Enforcement

43 When Cooperation-First & Enforcement Referrals Don t t Work Most Responsible Parties Fear Tarnished Public Image More Than LitigationL ceds.org/eqs Escalate Progressively: Ask elected officials for help, emphasizing your cooperative efforts Mobilize public support for official Maximize media coverage through actions Litigation as last resort

44 Winning Enforcement Agency Respect If an agency receives little public support, then don t t be surprised if compliance is poor exposed soil County water tank site eroded away for nine months synthetic mulch-grass seed Single referral got site stabilized in three days More Aggressive Options: Announce citizens will stabilize site. Threaten injunctive relief To get a single problem corrected Seek to understand agency enforcement criteria Use creative interpretation of criteria to get problem solved. If compliance is poor at many sites seek agency agreement before Going public Work with administration to identify solutions Support solutions with positive message: We know they care, but lack the resources to fix the problem Only then go adversarial

45 Smart Legal Strategies When Responsible Parties & Agencies Are Uncooperative ceds.org/sls Exhaust Cooperation First Research all litigation options to ID best Seek savvy, experienced attorney (minimal cost) Threat usually gets results 95% of time Legal precedent vs. specific incident

46 Help Expand The Watershed Advocates Stormwater BMP Database Report your findings at: ceds.org/bmpreport