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

6. Monitoring Methods Monthly monitoring Volunteer Observation
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 II Sources 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. Spatial heterogeneity in soil phosphorus concentration
77% of soils sampled – no phosphorus fertilizer recommended
Spatial heterogeneity in soil phosphorus concentration

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 bags (50 lbs. each) of (N-P-K)
June bags (50 lbs. each) of (N-P-K)
November bags (50 lbs. each) of (N-P-K)
This translates into
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. Reclaimed Water Nutrient Inputs
Average Rainfall 48.9 in
Estimated irrigation need in
1180 lbs
31 lbs
Fertilizer 2009

43. Sediment Phosphorus Concentration

44. Sediment Phosphorous Inputs

45. Sediment Copper Concentration
AET 1,300
AET 390

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