Load Reductions from Maintenance Measures and Fertilizer Control April 9, 2014
Acknowledgement and Disclaimer Michael Bateman, P.E. Northwest Florida Water Management District Results are from Florida MS4s. However, the concept is valid anywhere and results may be even more favorable in other parts of the southeast.
MS4 Discharges Are Contributing to Water Quality Violations & Impairments
MS4s Overall Responsibility Under the Law * : 1. Implement SWMP to MEP 2. Implement Programs Targeted at Specific Pollutants (for TMDLs) 3. Estimate Resultant Reductions in Loads 4. Evaluate Effectiveness *See 40 CFR Part 122.26(d)(2)v
Multiple Sequestration Mechanisms Occurring Swale Collection System Catch Basin Baffle Box Receiving Water
Routine Maintenance How do we Quantify Pollutant Removals? How does the costeffectiveness compare to conventional treatment?
Concept/Approach Can we answer the question: What is the nutrient content of the solids that we remove? If YES, then, can we develop a defensible, reproducible data set that we can use?
Participating Florida MS4s 1. Gainesville 2. Hillsborough County 3. Jacksonville 4. Lee County 5. Miami-Dade County 6. Orange County 7. Orlando 8. Pensacola/Escambia County 9. Sarasota County 10. Seminole County 11. St. Petersburg/Pinellas County 12. Stuart 13. Tallahassee 14. Tampa Thousands of Samples
Maintenance Practices Studied Street Sweeping Catch Basin Cleanout End-of-pipe BMP Cleanout Thousands of Samples
Types of Land Use Studied Commercial Highway Residential Thousands of Samples
Results of Study-Simplified Surprising! Good Correlation Among Particulates (Solids) Statistically Valid Values for TP and TN Turns Out No Real Difference Between Commercial, Highways, and Residential Land Use Similar Enough to Eliminate Distinction!!!
FSA Assessment Tool YES WE CAN develop a statistically valid, calibrated and verifiable relationship between particle mass & pollutants Provides defensible values for TP and TN Florida Department of Environmental Protection has approved the Final Report and methodology
Load Reduction Narrative Accompanying the Spreadsheet Narrative Title: Methodology for Calculating Nutrient Load Reductions Using the FSA Assessment Tool Provides Values for Nutrient Content and Default Values for Moisture Content and Density Instructions for Collection & Measurement of Solids and Moisture Content
Narrative: What the Tool Does Allows Collection of Fairly Rudimentary Measurements of Weight or Volumes While Generating Scientifically Defensible Values for TN and TP Removals
Narrative: How the Tool Does It Simple Math via Spreadsheet Establishes Mass of TN & TP per Kg of Solids Based on DRY MASS
Narrative: What is Needed from MS4 to Use the Tool Weights or Volumes of Stuff Measure Truck volume, Vactor Size, Sweeper Hopper, or Piles of Sediment Or Even Better, Weigh the Stuff
Narrative: How Get to Dry Mass? 1. Need Moisture Content if Measuring Weight 2. Need Specific Gravity if Measuring Volume Default Values Moisture Specific Content Gravity BMPs 26 1.36 Catch Basins 21 1.36 Sweepings 6 1.36 Specific Gravity of 1.36 = 84.9 pounds per cubic foot
Narrative Some Final Monitoring Needed for Moisture Content & S.G. One Year of Monthly Samples for each MS4 Permit Group Duplicate Monthly Samples for BMPs Catch Basins Sweepings Median Values Obtained can then be used in the Spreadsheet
Narrative Last Thing After One Year Sampling Then YOU ARE DONE with Chemistry Just Simple Measurements from Here Out Provides Real Pollutant Removal Values
St. Pete Nutrient Calculation November 2010- November 2011 Solids Removed - Pounds 5,263,800 TP Removed - Pounds 1,900 TN Removed - Pounds 2,970
Tallahassee Data & Calculations Collection Period (calendar year) Sweepings (Tons) Pounds Removed (*) TN Removed (Pounds) TP Removed (Pounds) 2009 1,994 3.74 Million 2,100 1,400 2010 2,629 4.94 Million 2,780 1,780 2011 2,624 4.94 Million 2,780 1,780 * Using 6% Moisture Content
Pinellas County TN & TP TN Removed- Pounds TN Removed -Pounds TN Removed- Pounds Activity FY 08/09 FY 09/10 FY 10/11 Total Sweepings 3,387 1,123 1,219 Vactor Spoils 441 794 579 TP Removed Pounds TP Removed- Pounds TP Removed Pounds Activity FY 08/09 FY 09/10 FY 10/11 Total Sweepings 2,172 720 782 Vactor Spoils 271 488 356
City of Orlando Raw Data & Calculation 16,754 cubic yards were collected from 46,382 curb miles swept. Total Volume Cubic Feet TP Removed Pounds TN Removed Pounds Sweepings 452,400 13,900 21,600
What s to Come?
Potential to Expand the Methodology What if We Were Concerned about Heavy Metals, Other Pollutants of Concern? What about Getting Credit for Other Management Practices?
Contact Information Michael Bateman, P.E. Michael.bateman@nwfwmd.state.fl.us 850-921-5846
Fertilizer Fun Facts Nitrogen fertilizer is virtually all synthesized One percent of the total world energy consumption goes towards fertilizer production It costs approximately $0.50 to produce a pound of nitrogen It costs approximately $500 to remove a pound of nitrogen from stormwater
Fertilizer Fun Facts Fertilizers reduce food costs by making land more productive There is some evidence that properly fertilized urban areas may have lower loads than unfertilized areas. There is evidence of a breakpoint beyond which additional fertilizer cannot be assimilated.
Fertilizer Control Model Fertilizer Ordinance Must be adopted, at a minimum, for nutrientimpaired water bodies Licensing and training Prohibited application period Fertilizer rates and methods Fertilizer-free zones Voluntary low-maintenance zones
Fertilizer Control Lessons Data deficit for effectiveness Very large sample size needed Application rates based on plant health and leaching Ordinance without enforcement will have a more limited impact Public education remains an important counter-balance
Questions