The document discusses a Clean Water Optimization Tool being developed by the Center for Watershed Protection to help municipalities develop cost-effective strategies for meeting water quality goals like the Chesapeake Bay Total Maximum Daily Load. The tool will evaluate practices like bioretention, permeable pavement, and land conservation. It will recommend strategies based on minimizing costs per pound of nutrient or sediment reduced. The tool is being piloted in Maryland's Eastern Shore and will incorporate local data on practice costs and effectiveness.

1. Stormwater Trends
Clean Water Optimiazation Tool
David J. Hirschman
Program Director
Virginia Office
djh@cwp.org

2. We Work Here…..
 National non-profit 501(c)3 organization
 21 staff
 Offices in MD, VA, NY, PA
• Distill research into practical tools
• Provide local watershed services
• Train others to manage watersheds
What we do

4. djh@cwp.org

5. Stormwater News & Gazette:
Late Breaking Headlines!

6. Job Duties: Counting
Runoff Volume & Pollutant
Loads
Want Ads:
Needed Immediately: Stormwater
Accountants

7. Stormwater Goes Quantitative
MS4 Wasteload Allocations – TMDLs
Pollutant Removal Rates for BMPs

8. “Not everything that can be counted counts, and
not everything that counts can be counted.”
-Albert Einstein

9. Stormwater part of obesity
epidemic
Diet Prescribed –
Volume Must Be Reduced!

10. Runoff Reduction Processes
Runoff Reduction is not just infiltration!
 Infiltration
 Canopy Interception
 Evaporation
 Transpiration
 Rainwater Harvesting
 Extended Filtration
Center for Watershed Protection

11. State (and many local) Stormwater Performance
Standards & Manuals are Changing*
 D.C. – 1.2” on-site retention
 DE – retain “resource protection event” (2.7”)
 WV MS4 – retain runoff from 1” rainfall
 MD – on-site retention using Environmental Site
Design
 Coastal GA – reduce runoff from 1.2” storm
 WI – Infiltration standards
 Others?
*Replacing previous “treat & release” & 80% TSS standards

12. Stormwater Style Goes Retro

15. New BMPs vs. Retrofits
(Shenandoah Valley MS4s
 Average Cost-Effectiveness ($ per pound of
Phosphorus Removed)
 New Retrofits = $56,000
 Retrofits/Conversions of Existing BMPs = $24,000 (some
½ of this)

16. Sports:
Contractors Roll Over Inspectors
in BMP Installation Bowl
Inspectors Fail to Show Up During
Critical Match-Up

17. Drainage Area Stabilized?
Installed too early during construction;
fouled with construction sediment
Inlet blocked temporarily during
bioretention installation

18. Make Sure Water Gets In!
Inlets blocked or small elevation
change diverts flow from inlet
Inlets unimpeded with pretreatment
stone strip or inlet channel

19. Style: Stormwater BMPs Go Shaggy
Is Clean-Cut A Thing of the
Past?

22. Finance: Investors Rush to
Purchase Stormwater Credits

23. Stormwater/Pollutant Trading
$
Pollutant
Reductions
Source: nrcs.usda.gov

24. Impact
Mitigation
Perceived
Impacts/Benefits
Not Everyone Thinks It’s a Great Idea!

25.  D.C. (up and coming)
 MN – Capital Regional Watershed District
 City of Fredericksburg, VA (policy stage)
 Chesapeake Bay
 Neuse River, NC
 MD Critical Areas
 Maine sensitive lakes
Some Existing Off-Site Compliance/Trading
Programs

26. Clean Water Optimization Tool for
Maryland’s Eastern Shore
funded by Town Creek Foundation

27. Clean Water Optimization Tool
Overview
The Center for Watershed, Inc. is developing a Clean Water
Optimization Tool.
• Municipalities can develop the lowest cost implementation
strategy possible to meet the Chesapeake Bay TMDL and
other local water quality goals
• Use defaults from the EPA Chesapeake Bay Program Office
and override options
• Develop strategies to optimize by cost, pollutant, or user
defined value

28. Clean Water Optimization Tool
Overview
• Pilot areas on the Eastern Shore are Wicomico Co., Talbot Co.,
Kent Co., and Queen Anne’s Co.
– Case studies
• Robust communications strategy will guide widespread
dissemination and help increase the credibility of the Bay
restoration effort
• Disseminate the Clean Water Optimization Tool
– Website, newspaper, emails, etc.

29. Clean Water Optimization Tool
Background and Importance of This Work
Cost for meeting WIP Targets are all over the place
Source: MDE Nutrient Allocation Files (CBP Model 5.3.2.), MDE prepared 2010 Progress MAST loading decks, and the Core Planning Team
Loading Decks
Urban Sector Bar Graphs Representing TN and TP Loads for 2010 Progress,
2017 Interim Strategy and Target, and 2025 Final Strategy and Target.

30. Clean Water Optimization Tool
Background and Importance of This Work
Innovative BMPs can substantially reduce costs
Annual cost to remove equivalent annual TN load
The cost-effectiveness of stormwater controls for nitrogen removal.
Practice Type of practice Equivalent Annual cost
($/lb N/IC1 ac)
Bag filter Structural $691
Bioretention (new, suburban) Structural $335-$6342,3
Wet pond (new) Structural $7334
Street sweeping Non-structural $1655
1 Based practice life expectancy of 10-years.
2 Costs for other practices based on King and Hagen (2011) over a 20-year period and an urban loading rate of 14.1 lb TN/acre.
3 Range represents a removal efficiency of 45% and 85% from Simpson and Weammert 2009.
4 20% removal efficiency for TN from Simpson and Weammert 2009
5 Berretta et al. 2011 expressed as lb N/year

31. Illicit discharge elimination is a cost effective
approach to nutrient management
Common sense housekeeping practices can be
extremely cost effective also

32. 36 Urban Practices:
• Pavement/Impervious Cover
• Rooftop
• Bioretention
• Filtering/Infiltration
• Channels
• Ponds/Wetlands
• Conservation/Enhancement
• Land Use Change
• Social/Programmatic
• Also Includes cross-sector trading and user-defined options
Clean Water Optimization Tool
Cost
BMPs

33. Clean Water Optimization Tool
Cost
Cost Components
• Initial Costs - design, construction, land costs
• Operation and Maintenance – annual routine maintenance,
intermittent maintenance, county implementation cost
(inspection and enforcement)
• Annualized life cycle costs are estimated as the annual bond
payment required to finance the initial cost of the BMP (20-
year bond at 3%) plus average annual routine and intermittent
maintenance costs.

34. Clean Water Optimization Tool
Cost
User-Adjusted Values
User-Adjusted Input Default
Land Cost per Developable Acre $100,000
% Project Acres Developable 50%
# Years to Project Cost Estimate Over 20
County-Specific Cost Adjustment 0.97

35. Clean Water Optimization Tool
Cost
• Additional BMP Benefits should be quantified:
– Public Health/ Safety
– Public Education
– Recreation
– Neighborhood Beautification
– Urban Heat Island
– Carbon Footprint
– Wildlife Habitat
– Stream Habitat
– Flood Control

36. Clean Water Optimization Tool
Research – Pollutant Load and BMP effectiveness
BMP Effectiveness Component
– Structural practices based on Chesapeake Bay Program Expert
Panel Recommendations
– Land use changes
– Programmatic practices are based on various sources
• IDDE Expert Panel
• Watershed Treatment Model (WTM)
• Previous CWP publications, research, and experience

37. Clean Water Optimization Tool
Steps to Use the Tool
• Step 1: Desktop Assessment/Informative Exercise
– Use local knowledge
– Accepted data sources
• National
• State
• County
• Town Field work in the South Prong, Wicomico
County

38. Clean Water Optimization Tool
Steps to Use the Tool
• Step 2: Entering Practical Estimates
– Apply information gathered to selected/accepted BMPs
• This will allow practical maximums to be set
– Practical maximum amount of permeable pavement to be installed,
for example
– Apply local knowledge and practical experience
• For example, sand filters may not be readily accepted by the
community
– This would limit installation of this particular practice

39. Clean Water Optimization Tool
Steps to Use the Tool
• Step 3: Override Default Cost Values & Specify
Programmatic Information
– Enter information about local costs, if available
• Important for realistic scenario development
– Modify land cost, and length of time to project costs
– Estimate parameters for programs
• Quantity of Promotional and education materials for a pet
waste program, for example

40. Clean Water Optimization Tool
Steps to Use the Tool
• Step 4a: Enter Structural Practices Already Installed
– These entries will count towards TMDL goals
• For example, over an entire county there may be 20 acres treated
by a bioretention, these can be aggregated and entered as one

41. Clean Water Optimization Tool
Steps to Use the Tool
• Step 4b: Enter High Priority Practices
– Enter information about high priority practices
• Practices that are publicly accepted
• Practices proven to be effective
• High comfort level with installation/maintenance
– These practices will be weighted heavier during
optimization
• Estimated costs will not be changed
Outfall net in Talbot County

42. Clean Water Optimization Tool
Steps to Use the Tool
• Step 5: Optimize
– Select optimization goals
• Based on cost per pound of nitrogen reduction
• Based on cost per pound of phosphorus reduction
• Based on cost per pound of sediment reduction
• Based on a nitrogen and phosphorus weighting
– 50/50 would equally weight optimization based on cost per pound of
N AND cost per pound of P
– Results will show pertinent information
• Pounds reduced, if less than goals
• Estimated cost
• Number of acres requiring treatment for each practice to achieve
total reductions

43. Center for Watershed Protection
Questions/Comments
Sadie Drescher
srd@cwp.org or sdrescher@chesapeakebay.net
410.461.8323 xt 215 or 410-267-5717
Bill Stack, P.E.
bps@cwp.org or wstack@chesapeakebay.net
410.461.8323 xt 222 or 410-267-5717