Maximizing Phosphorus Load Reduction
Download as PPTX, PDF1 like1,050 views
The presentation discusses phosphorus and its significant role in freshwater systems, highlighting its sources, including anthropogenic contributions and natural weathering. It outlines methods for reducing phosphorus load in urban runoff using strategies like sedimentation, physical filtration, and reactive filtration, emphasizing the importance of innovative solutions. Case studies demonstrate effective phosphorus removal through various treatment practices, though regulatory challenges remain in assigning specific credit for best management practices.
Maximizing Phosphorus Load Reduction
- 1. www.ContechES.com Maximizing Phosphorus Load Reduction Presented By: Derek M. Berg Southeast New York Stormwater Conference October 15, 2014
- 2. Phosphorus: What is it and where does it come from? How do we address Phosphorus in Urban Runoff? Raising the bar on phosphorus removal the latest research www.ContechES.com and innovation Agenda
- 3. Why do we care about Phosphorus? Aren’t nutrients a good thing? Phosphorus is usually the most limiting nutrient www.ContechES.com in freshwater systems Too much of a good things makes watersheds sick
- 4. www.ContechES.com Sources of Phosphorus Weathering of calcium phosphate minerals, especially apatite Anthropogenic (human) P is often much greater than natural inputs of P in many watersheds Common anthropogenic sources: agriculture, wastewater, excess fertilizer, faulty septic Wildlife can also contribute significant amounts of phosphorus to local watersheds
- 5. www.ContechES.com Forms of Phosphorus Total P: Is most common measure of phosphorus concentrations in runoff and watersheds. TP = DIP + DOP + PP We often measure both particulate and dissolved fractions of phosphorus o Dissolved P o Ortho P o Soluble Reactive P TP is most commonly regulated
- 6. www.ContechES.com Phosphorus in Lakes Lake Productivity Classification Total Phosphorus mg/L Ultra-oligotrophic <5 Oligotrophic 5-10 Mesotrophic 10-30 Eutrophic 30-100 Hypereutrophic >100 Phosphorus concentrations in untreated stormwater are often many times higher than those in receiving waters!
- 7. www.ContechES.com Phosphorus in Stormwater • Phosphorus is often in both solid and soluble forms • Solid phosphorus tends to be associated with finer particles • Ratio of solid/soluble is often variable. Research suggests 50/50 split is a reasonable estimate (NYSDEC Chap. 10) • Previously captured particulate can be leached as soluble P
- 8. www.ContechES.com Phosphorus in Stormwater Source: NYSDEC Chap. 10 NYS Stormwater Management Design Manual
- 9. How do we address TP in runoff? www.ContechES.com • Good Housekeeping • Runoff Reduction • Sedimentation • Biofiltration • Media Filtration
- 10. www.ContechES.com (Not So) Good House Keeping Source Washington State Water Quality Consortium
- 11. Runoff Reduction Preventing runoff from occurring or reaching receiving waters eliminates all of the pollutants that would be carried by that runoff www.ContechES.com Reduce runoff via LID site design concepts Retain water onsite o RWH o Bioretention o Pervious pavers o Infiltration Systems
- 12. Removing Phosphorus With Treatment Three primary mechanisms to removal Phosphorus from Urban runoff: Sedimentation Physical Filtration Reactive Filtration www.ContechES.com
- 13. www.ContechES.com Sedimentation Examples: Ponds, Vaults, Detention Systems, Hydrodynamic Separators • Slow water down and allow solids to settle • Longer residence time = finer particles captured • Phosphorus removal often tied to residence time • No capture of dissolved/soluble P • Leaching possible
- 14. www.ContechES.com Physical Filtration Examples: Screening, Media Filters, Sand Filters, Biofilters, Infiltration • Physical barrier to solid particles • Good control of TSS and attached pollutants • Good removal of particulate metals and phosphorus • No removal of dissolved/soluble pollutants • Leaching possible • Longevity must be considered
- 15. www.ContechES.com Maximizing TP Removal
- 16. www.ContechES.com Reactive Filtration/ Processes Reactive filtration media with an affinity for target pollutants, organic matter, • Often works in parallel with physical filtration and/or sedimentation • Target pollutant is bound to media via adsorption, ion exchange etc. • Effective removal of soluble/dissolved pollutants • Boosts overall pollutant load reduction • Prevents leaching
- 17. www.ContechES.com Common Treatment Practices
- 18. www.ContechES.com Wet Pond (Sedimentation)
- 19. SandFilter (Sedimentation, Physical Filtration) www.ContechES.com
- 20. www.ContechES.com Bioretention/Biofiltration Source: NYSDEC Chap. 5 NYS Stormwater Management Design Manual
- 21. Raising the Bar on TP Removal With Innovative www.ContechES.com Solutions
- 22. www.ContechES.com Case Study 4 Bioretention Soil Amendment Fleming College, Ontario
- 23. www.ContechES.com Bioretention Soil Mix Amendment with Phosphorus-Adsorbing Sorbtive Media Fleming College, Centre for Alternative Wastewater Treatment Ontario, Canada Case Study 3
- 24. Results: TDP Removal Efficiency www.ContechES.com 100 90 80 70 60 50 40 30 20 10 0 TDPs Influent Conc (0.2 mg/L) TDPs Influent Conc (0.4 mg/L) TDPs Influent Conc (0.6 mg/L) TDPs Influent Conc (0.8 mg/L) % TDP Removal Control Sorbtive Media 5% Sorbtive Media 10%
- 25. Lakewood Park - Chautauqua Lake Retrofit DI’s • Sorbtive Media applied in a layer above underdrain pipe www.ContechES.com
- 26. www.ContechES.com 2 Filterra® Bioretention
- 27. www.ContechES.com Filterra Overview Optimized media gradation Functions as living biological system Simple Maintenance Consistent field removal of >60% TP Can be deployed boxless
- 28. The Stormwater Management StormFilter® www.ContechES.com
- 29. www.ContechES.com PhosphoSorb Media Lightweight, oxide coated, non toxic, reactive media Lab testing showed excellent removal of dissolved P TAPE and TARP field testing showing >70% TP reduction and excellent removal of DP
- 32. Fleming College www.ContechES.com Soil Mix Composition Sand Peat Moss Sorbtive® Media AI 28x48 • High surface area phosphorus-adsorbing media • Sand-like gradation • Added to soil mix on volume basis, ranging 0% - 17% Soil components mixed in buckets of 2 front-end loaders
- 33. Regulatory Challenges NYSDEC 80% TSS, 40% TP threshold is essentially pass fail Currently no review process in place to assign specific TP www.ContechES.com credit to BMPs Limited value in achieving >40% TP without means of taking regulatory credit In load sensitive watersheds
- 35. www.ContechES.com Questions??? Derek Berg dberg@conteches.com 207-885-6174