Cost/benefit Analysis of Stormwater Pond Alternative Management Controls Demonstration Project

1. Cost/benefit Analysis of Stormwater Pond Alternative Management Controls Demonstration Project Mark Clark Wetlands and Water Quality Extension Specialist Partnership for Water, Agricultural and Community Sustainability at Hastings Soil and Water Science Department

2. Acknowledgement • Grand Haven CDD Board and Community • Dr. Stephen Davidson • Barry Kloptosky and Tom Lawrence • Aquatic Systems Inc. and Austin Outdoor • Jim Cook • Byron Kort • The many volunteers who assisted with data collection and sampling, without their help and dedication, projects like this can’t happen.

3. Outline • Review of treatments • Monitoring methods • Part I -Key findings for algae, water quality and aquatic life • Part II - Key findings for fertilizer, reclaimed water, soils and sediments • What next

4. Grand Haven CDD Symposium(January 22, 2008) • “What ecologically sound and fiscally responsible measures can the governmental organizations, Hampton Golf, and all property owners/residents of Grand Haven take to: 1. Maintain the health of our storm water detention ponds (aka “lakes”)? 2. Correct and prevent recurring problems such as algae blooms?”

5. Aeration Littoral Shelf Planting Carp Control / SAV Copper Sulfate Alternative Lake Treatments

6. Monitoring Methods • Monthly monitoring • August 13,2009 -January 15, 2010 • Volunteer Observation • SAV cover (% floating, % submerged), • Water Clarity (scale 1-5) • Aquatic life assessment • (none = 0, infrequent = 1, common = 3, abundant = 10) • Water sample NOx, TKN, TP (TN, TP, TN:TP) • Photo Interpretation • Floating filamentous algae (% cover) • Emergent (% exotic, % native) • Color/Clarity index (scale 1-5

7. Survey Data Sheet

8. Example Photo Interpretation

9. Import image to Coral Point Count Program

10. Overlay 100 random points and classify 36% open water 15% floating filamentous algae 5% native emergent 42% exotic emergent

11. Color/Clarity Index - #1 • Clear, no green color

12. Color/Clarity Index - #2 • Clear, some green color

13. Color/Clarity Index - #3 • Slightly cloudy, strong color

14. Color/Clarity Index - #4 • Strong Cloudy, Strong Color

15. Color/Clarity Index - #5 • Visible particles, bright color

16. Part I Effects of Grand Haven Stormwater Pond Alternative Treatment Practices on Algae, Water Quality and Aquatic Life

17. Findings - Which of the 4 pond treatment methods was the most effective in controlling algae? Which of the 4 pond treatment methods was the least effective in controlling algae? 13.7% 34.3% 16.8%

18. Floating and Submerged SAV

19. Water Clarity and Color/Clarity Index

20. Native and Exotic Emergent Vegetation

21. Zooplankton Abundance

22. Snail Abundance

23. Insect Abundance

24. Fish Abundance

25. Reptile and Amphibian Abundance

26. Bird Abundance

27. Water Column Total Nitrogen

28. Water Column Total Phosphorus

29. TN:TP Ratio

30. Treatment Alternative/Study Cost

31. Estimated Annual Maintenance Cost of Alternative Treatments

32. Treatment Alternative Summary (Copper Sulfate) • Positive • Low cost, • fast acting, • one of two most effective at filamentous algae control • Negative • Increased nutrient levels in water column • Short-term effect with need for repeat treatments • Reduced water column clarity • Negative effects on aquatic life • Source of elevated copper levels in sediment

33. Treatment Alternative Summary (Aeration with Microbes) • Positive • Increased abundance of aquatic life • Some improvement in water column total phosphorous concentration • Negative • Least effective treatment at filamentous algae control • Most expensive treatment to implement

34. Treatment Alternative Summary (Littoral Shelf Planting) • Positive • One of most effective treatments for floating filamentous algae control • Highest water clarity and lowest color rating of treatments • Highest aquatic life abundance in some categories • Lowest water column nitrogen and phosphorus levels • Only treatment with total nitrogen to total phosphorous ratio above 20 • Negative • Perceived benefits may rely heavily on SAV component of treatment • As implemented in study this treatment is prone to invasion by exotics and nuisance species as well as aesthetic concerns • Moderate cost of maintenance

35. Treatment Alternative Summary (Submerged Aquatic Vegetation) • Positives (based on August 13, 2009 sampling) • Could significantly reduce total nitrogen and phosphorus concentrations in water column • Could provide best water clarity • Could improve some aquatic life categories • Negative • Treatment did not meet homeowner acceptability standard in two out of three ponds being assessed

36. Part IISources of Nutrients to Grand Haven Stormwater Ponds: Fertilizers, Reclaimed Water, Soils and Sediment

37. Methods • Upland Soils – Mehlich-1 extractable P • Fertilizer Application – Austin Outdoor • Reclaimed Water - CDD • Sediment – • Ponar dredge • Analysis for TP, TCu, Water extractable P

38. 77% of soils sampled – no phosphorus fertilizer recommended Spatial heterogeneity in soil phosphorusconcentration

39. Fill Soils Phosphorus Concentration Native Soil Fill Soil

40. Fill Soil Phosphorus Inputs 5,450% 4% 20%

41. Common Area Fertilizer Inputs • Application date Total amount and formulation • March 2009 71 bags (50 lbs. each) of 8-2-12 (N-P-K) • June 2009 71 bags (50 lbs. each) of 10-0-15 (N-P-K) • November 2009 57 bags (50 lbs. each) of 19-0-19 (N-P-K) • This translates into • 1180.5 lbs of nitrogen • 71 lbs of phosphorus as phosphate (P2O5) or • 31.24 lbs as elemental phosphorus.  • Upper end UF/IFAS recommended rate for nitrogen • 2-5 lbs. N/1000 sq ft / yr

42. 1180 lbs 31 lbs Fertilizer 2009 Reclaimed Water Nutrient Inputs Average Rainfall 48.9 in Estimated irrigation need 20-35 in

43. Sediment Phosphorus Concentration

44. Sediment Phosphorous Inputs

45. AET 1,300 AET 390 Sediment Copper Concentration

46. Source of Copper in Sediment Total Copper/OM R2 0.83

47. Part II summary • Fill soils and underlying pond sediments have elevated phosphorus concentrations which explain some variability between pond “symptoms”. • Sediment sources will be difficult if not impossible to control. • Fill soil sources can be managed to some degree by minimizing leaching and surface water connections. • Significant reductions in nutrient inputs and soil leaching can be attained by reducing irrigation. • Copper concentrations in some pond sediments are high and likely effecting some aquatic organisms based on EPA listed Apparent Effect Thresholds (AET). • Source of copper in sediments is most likely from copper sulfate treatments.

48. What Next? • Continue LSP treatment ponds (6, 7, 17) with the following modifications • Exotic and nuisance emergent management • Low density stocking of carp • As needed algae control • Develop quantitative acceptability threshold to guide operations manager and contractor

49. Floating Treatment Wetland? Beemats, - New Smyrna Beach, FL ACF Inc., Jacksonville, FL Hidrolution, Spain Positive Likely improve water quality, suppress SAV, algae Avoids homeowner shoreline Uncertainties Treatment efficiencies unknown No direct suppression of filamentous algae along littoral shelf Optimization (harvesting) unknown