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Surviving the Local WIP: a practical guide on nutrient accounting for the Chesapeake Bay TMDL. Contact Info. Tom Schueler Chesapeake Stormwater Network and EPA Chesapeake Bay Program Stormwater Coordinator Baltimore, MD watershedguy@hotmail.com www.chesapeakestormwater.net www.cbstp.org.
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Surviving the Local WIP: a practical guide on nutrient accounting for the Chesapeake Bay TMDL
Contact Info Tom Schueler Chesapeake Stormwater Network and EPA Chesapeake Bay Program Stormwater Coordinator Baltimore, MD watershedguy@hotmail.com www.chesapeakestormwater.net www.cbstp.org
Key Topics • Some nutrient math • Some basics on the Bay TMDL • 12 easy steps to comply with your local load allocation • Discussion
Technical Bulletin # 9Nutrient Accounting Methods to Document Local Stormwater Load Reductions in the Chesapeake Bay • Nutrients and the Chesapeake Bay • Why we need to become nutrient accountants • What we know about nutrients and stormwater • Tools to estimate nutrient loads • Defining the local baseline load • Pollutant removal rates for urban BMPs * • Strategy for achieving local load reductions • Analyzing the cost of implementation * official CBP rates and proposed interim planning rates
Urban Nutrients Where do they come from?
Much of the nitrogen in urban runoff is derived from atmospheric deposition, either in the form of dryfall or wetfall
Other sources of nitrogen in urban runoff include: • Washoff of fertilizers • Nitrogen attached to eroded soils and streambanks • Organic matter and pet wastes on IC
What we know about turf and its management in the Bay Watershed • 3.8 million acres of turf • Represents 9.5% of watershed area • Exceeds area devoted to row crops (corn, wheat, soybeans) • 75% of turf is home lawn
Nitrogen EMCs for different urban land covers Source; CWP, 2003 Runoff sampling shows that lawn runoff is very high in nitrogen. Also, rooftop runoff concentration shows effect of atmospheric deposition
What do we know about home lawns and nutrients? About 50% to 65% fertilize their yard 15 to 20% hire lawn care company Average of two applications per year 50% of homeowners over-fertilize Estimated N Fertilizer inputs by lawns: 215 million lbs/yr
Bottom Line of Chesapeake Bay TMDL For Urban Suburban Sector ~25 to 30% TP and TN load reductions needed from existing development (plus sediment reductions) No increase in future load as a result of growth and development 60% of the reductions to be achieved by 2017 100% by 2025
Some folks think the WIP process is scary • Billions in potential costs • Short planning horizon (draft plan due Dec 1, 2011) • Potential regulatory liability • High planning costs • Lots of complex documents • = major local headaches
The WIP Process is not as Scary as it Looks • Each state works with its local governments to develop strategies for nutrient reduction • The jurisdictional unit could be a MS4 permitee, planning district commission, county or conservation district, depending on the state • The liability for not meeting the load reductions is a state liability, and not a local one (unless tied into MS4 permit)
What to expect: • Locals will need to submit data, have a strategy and report on BMP implementation • Locals will need to follow state and/or CBP approved procedures for tracking and verifying BMPs • States have the responsibility for aggregating local data and submitting it to EPA to show progress in load reductions
The WIPs are a long term process • Progress is assessed based on two year milestones • Implementation of the WIP is a 15 year iterative process • Many opportunities for adaptive management and collaboration
Check with your state agency to find who is responsible for WIPs in your state and the process they will follow • (they differ a lot)
Initial Tasks for the Watershed Team • Obtain the local nutrient reduction allocation from the state or regional agency administering the TMDL • Coordinate with the state TMDL agency to better understand their local expectations • Analyze local land use and land ownership data to determine what part of their load allocation can be legitimately excluded • Identify which local agencies or stakeholders have primary responsibility to implement the dozen available urban BMP credits • Check to see if agencies are already implementing a credit, or could do so through modest changes to existing programs. • Determine how the credits should be documented and reported to the appropriate state or regional agency
# 2 Take credit for fertilizer reductions on urban turf • Reflects recent MD and VA P Ban in Fertilizer • Modeled as an application reduction, with an estimated 17 to 19% TP reduction in urban loads • Research in other regions put it closer to 10 to 12% • TN reductions are minor unless regional education campaign program to reduce N fertilization
Urban Nitrogen Fertilizer Reduction • Right now, none of our residential stewardship programs focuses on reducing urban fertilizer use, despite the fact it is the most cost effective nutrient reduction strategy • 1.5 million acres of home lawn are fertilized • Very limited incentives beyond free soil testing and passive technical advice • We send conflicting messages to homeowners about lawn fertilization
Fertilizer Message 1 • Get a soil test, and if adequate P is present, then select P-free fertilizer • Calibrate your spreader • Follow label directions of weed/feed products • Use slow release N fertilizer in Fall only • Apply 1 to 4 lbs of actual N per 1000 square feet • Do not apply to frozen soils, impervious cover or in advance of a thunderstorm • Use a composting lawn mower and recycle composted leaves over yard • Set mower height at three inches • Irrigate only after extended drought • Don’t washout your spreader over IC
Fertilizer Message 2 • Tommy makes an offer you can’t refuse! • Keep your spreader in the garage for the next three years to protect the Bay • Save 150 bucks and three weekend days • If you still like the look of your lawn after three years we will buy back your spreader for $150 • If you think your lawn looks like crap, we will pay for a lawn makeover worth $500 (using our green lawn service)
The Competing Fertilization Message • Consumer surveys indicate the primary and almost exclusive sources for information on fertilizing their lawns are: • TV and radio commercials • Product labels in the big box store • Store attendants • Recommendation from their lawn care company
# 3 Take nutrient reduction credits for more stringent stormwater requirements at redevelopment projects • Calculate the expected acres of impervious cover slated for redevelopment • Estimate the runoff capture volume and design level using new regs • Calculate the aggregate nutrient reduction credit
# 4 Become an Early Adopter of Stormwater Regulations This ensures that your nutrient liability won’t continue to increase
Variability in Bay State Stormwater Regulations • Considerable confusion in terminology among the states (ESD, LID, RR, treatment trains) • Each state/locality is on a different schedule for implementing them (2009 to 2013) • Each state has a unique hydrologic performance standard • Differential standards for new and redevelopment • Individual sites may not fully comply with standard
Will the new standards lead to nutrient neutrality for new development projects in the future ?
What is an acceptable runoff nutrient load? Same Analysis Yield an Acceptable TN Load of 4.4 lbs/acre Results differ slightly for each state based on distance to the Bay
What local safeguards are needed to ensure the load limits are actually achieved on the ground? • Practices designed in accordance with Bay-wide Design Specs • Post-construction certification that it was installed properly and works • Municipality meets minimum performance standards for: • ongoing performance inspections maintenance enforcement
# 5 Take Credit for Community Reforestation • Set goal to reforest 5% of current turf cover • 10 to 1 Rule (ten acres of reforestation equals one acre of impervious cover treated) • CSN and VADCR spreadsheet rates are about the same • Get extra credit for • Treating runoff from adjacent IC • Stream or shoreline buffer upgrades ?
# 6 Take credit for current and future stream restoration projects • High nutrient reduction rates for qualifying projects • Provides both a local benefit and a Bay benefit • Generally popular with the public • Cost competitive with pond retrofits
CBP BMP Panel to Update Stream Restoration Rates • U of MD Literature Review • Review of 20 + studies on various parts of the urban stream nutrient cycle • Develop concept model for predicting rates • Should be done by early 2012
What’s a Qualifying Project? Can’t just dump rip-rap Comprehensive stream design Flood plain re-connection Minimum reach size In-stream habitat features
# 7 Re-tool your stormwater maintenance program Inspect the performance of your existing BMP inventory Field Research Indicates about 30% of the BMP Inventory needs a makeover Significant nutrient reductions are possible through these low cost “BMP makeovers” Performance downgrades must be reflected in local WIP baseline load By Retooling existing Maintenance Budget, it is possible to eliminate eyesores and clean the Bay
# 9 Take the Mass Credit for Intensive Street Sweeping • New CBP Method based on Actual Pollutant Mass Picked Up • Qualifying Frequency and Technology • Incentive for Sweeping Crews to Maximize Pickup
# 9 Investigate Septic Hookups and Upgrades • Key Strategy for TN removal • Relict septics in sewered catchments • Upgrade N technology in existing septics • Sewer extensions and cluster satellites • CBP Rates available
# 10 Take Credit for Eliminating Illicit Discharges • For chronic and episodic sewage discharges that are physically eliminated • Reduction based on rate of dry weather flow and outfall concentration above background levels • CWP research indicates this can be an important strategy in some urban watersheds available
# 11 Retrofit Existing Stormwater Ponds Source: CWP
# 12 Residential LID Retrofits Subsidies, technical assistance, stormwater utility credits and other incentives to build LID retrofits on private land
The Cost Challenge The weakest link in local WIPs are accurate cost data for practices Need to acquire better cost data and share it Possibility of Bay-wide database Millions vs. billions