cost/benefit analysis of stormwater pond alternative management controls demonstration project

Cost/benefit Analysis of Stormwater Pond Alternative Management

Controls Demonstration Project

Mark Clark

Wetlands and Water Quality Extension SpecialistPartnership for Water, Agricultural and Community Sustainability at Hastings

Soil and Water Science Department

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.

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

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?”

Alternative Lake TreatmentsAlternative Lake Treatments

Littoral Shelf PlantingLittoral Shelf PlantingAerationAeration Carp Control / SAVCarp Control / SAV Copper SulfateCopper Sulfate

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

Survey Data Sheet

Example Photo Interpretation

Import image to Coral Point Count Program

Overlay 100 random points and classify

36% open water15% floating filamentous algae5% native emergent42% exotic emergent

36% open water15% floating filamentous algae5% native emergent42% exotic emergent

Color/Clarity Index - #1

• Clear, no green color

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

Color/Clarity Index - #3

• Slightly cloudy, strong color

Color/Clarity Index - #4

• Strong Cloudy, Strong Color

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

Part I

Effects of Grand Haven Stormwater Pond Alternative Treatment Practices on Algae,

Water Quality and Aquatic Life

-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?

Floating Filamentous Algae by Pond Treatment(Photo Interpretation)

0

5

10

15

20

25

30

35

40

45

CuSO4 Aeration LSP

Treatment

Fil

am

en

tou

s A

lga

e,

% c

ov

er

b

a

b

13.7% 16.8%34.3%

Floating - Submerged Aquatic Vegetation by Pond Treatment

(Volunteer Observation)

0

5

10

15

20

25

30

CuSO4 Aeration LSP

Treatment

Flo

ati

ng

SA

V,

% c

ov

er

b

a

ab

Submerged - Submerged Aquatic Vegetation by Pond Treatment

(Volunteer Observation)

0

10

20

30

40

50

60

70

CuSO4 Aeration LSP

Treatment

Su

bm

erg

ed

SA

V,

% c

ov

er

b

ab

a

Floating and Submerged SAV

Water Clarity and

Color/Clarity Index

Water Clarity by Pond Treatment

(Volunteer Observation)

1.5

1.7

1.9

2.1

2.3

2.5

2.7

2.9

CuSO4 Aeration LSP

Treatment

Cla

rity

In

de

x

a

a

b

Color/Clarity Index by Pond Treatment

(Photo Interpretation)

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

CuSO4 Aeration LSP

Treatment

Co

lor/

Cla

rity

in

de

xa a

b

Native Emergent Vegetation by Pond Treatment

(Photo Interpretation)

0

2

4

6

8

10

12

14

16

18

20

CuSO4 Aeration LSP

Treatment

Na

tiv

e E

me

rge

nt

Ve

ge

tati

on

, %

co

ve

r

b

ab

a

Exotic Emergent Vegetation by Pond Treatment

(Photo Interpretation)

0

5

10

15

20

25

CuSO4 Aeration LSP

Treatment

Ex

oti

c E

me

rge

nt

Ve

ge

tati

on

, %

co

ve

r

b

b

a

Native and

Exotic Emergent Vegetation

Zooplankton Abundance

Zooplankton Abundance by Pond Treatment

0

0.2

0.4

0.6

0.8

1

1.2

CuSO4 Aeration LSP

Treatment

Av

era

ge

Ab

un

da

nc

e

b

ab

a

Snail Abundance

Snail Abundance by Pond Treatment

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

CuSO4 Aeration LSP

Treatment

Av

era

ge

Ab

un

da

nc

e

b

a

ab

Insect Abundance

Insect Abundance by Pond Treatment

0

0.5

1

1.5

2

2.5

CuSO4 Aeration LSP

Treatment

Ave

rag

e A

bu

nd

ance

b

ab

a

Fish Abundance

Fish Abundance by Pond Treatment

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

CuSO4 Aeration LSP

Treatment

Ave

rag

e A

bu

nd

ance

b

a

a

Reptile and Amphibian Abundance

Reptile and Amphibian Abundance by Pond Treatment

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

CuSO4 Aeration LSP

Treatment

Av

era

ge

Ab

un

da

nc

e

a

a

a

Bird Abundance

Bird Abundance by Pond Treatment

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

CuSO4 Aeration LSP

Treatment

Ave

rag

e A

bu

nd

ance

a

a

a

Water Column Total Nitrogen

Water Column Total Nitrogen by Pond Treatment

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

CuSO4 Aeration LSP

Treatment

Nit

rog

en C

on

cen

trat

ion

, mg

/L

a

b b

Water Column Total Phosphorus

Water Column Total Phosphorus by Pond Treatment

0

0.02

0.04

0.06

0.08

0.1

0.12

CuSO4 Aeration LSP

Treatment

Ph

os

ph

oru

s C

on

ce

ntr

ati

on

, m

g/L

b

a

c

TN:TP Ratio

Water Column Ratio of Total Nitrogen to Total Phosphorus by

Pond Treatment

0

5

10

15

20

25

30

CuSO4 Aeration LSP

Treatment

TN

:TP

Rat

io

a

b

b

Treatment Alternative/Study Cost

$/pond $/pond/monthCopper sulfate 649$ 72$ Aeration 7,943$ 882$ LSP* 3,938$ 438$ SAV** 799$ 89$

* Includes $1,367/pond, $151/pond/month cost of plantremoval from pond 6

** Cost only for corrective algae and weed control

$/pond/yr $/pond/monthCopper sulfate 868$ 72$ Aeration* 863$ 72$ LSP** $ 720 - 960 $ 60-80SAV*** -$ -$

* Per acre cost, does not include electricity** Unofficial quote

*** Does not include corrective treatments

Estimated Annual Maintenance Cost of Alternative Treatments

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

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

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

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

Part II

Sources of Nutrients to Grand Haven Stormwater Ponds: Fertilizers, Reclaimed

Water, Soils and Sediment

Methods

• Upland Soils – Mehlich-1 extractable P• Fertilizer Application – Austin Outdoor• Reclaimed Water - CDD• Sediment –

– Ponar dredge– Analysis for TP, TCu, Water extractable P

50%27%10%13%Grand Haven

29%14%29%29%G

60%40%0%0%F

100%0%0%0%E

40%20%40%0%D

57%29%0%14%C

57%29%14%0%B

11%56%0%33%A

Very HighHigh MediumVery LowCatchment

50%27%10%13%Grand Haven

29%14%29%29%G

60%40%0%0%F

100%0%0%0%E

40%20%40%0%D

57%29%0%14%C

57%29%14%0%B

11%56%0%33%A

Very HighHigh MediumVery LowCatchment

Soil Test Levels of Phosphorus in Grand Haven

0%

10%

20%

30%

40%

50%

60%

Very Low Medium High Very High

Phosphorus Test Level

% o

f so

ils t

este

d

Spatial heterogeneity

in soil phosphorus

concentration

77% of soils sampled – no phosphorus fertilizer recommended

Fill Soils Phosphorus Concentration

Fill SoilFill SoilNative SoilNative Soil

Fill Soil Phosphorus

Inputs

Upland Soil Mehlich-1 Extractable Phosphorus

( mean and range)

0.0

50.0

100.0

150.0

200.0

250.0

Native soil Fill soil Common area Turf Residential Turf

Sampling location

Ph

os

ph

oru

s c

on

ce

ntr

ati

on

, m

g/L

a

a

a

b

Upland Soil pH(mean and range)

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

Native soil Fill soil Common area Turf Residential Turf

Sample location

pH

aa a

b

5,450% 4% 20%

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 200957 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

Reclaimed Water Nutrient Inputs

Volume used

Year (gallons)(inches per

year)(inches per

week) (total lbs.) (total lbs.)

2005 52,846,100 142 2.73 4,057 6.80 2,117 3.552006 66,693,900 179 3.45 5,121 8.58 2,672 4.482007 81,246,300 218 4.20 6,238 10.50 3,255 5.452008 68,599,300 184 3.55 5,267 8.83 2,748 4.602009 42,167,900 113 2.18 3,238 5.43 1,689 2.83

Irrigation Rate Nitrogen

Volume used

Year (gallons) (total lbs.)(lbs. per 1000

sq ft.) (total lbs.)(lbs. per 1000

sq ft.)

2005 52,846,100 142 2.73 4,057 6.80 2,117 3.552006 66,693,900 179 3.45 5,121 8.58 2,672 4.482007 81,246,300 218 4.20 6,238 10.50 3,255 5.452008 68,599,300 184 3.55 5,267 8.83 2,748 4.602009 42,167,900 113 2.18 3,238 5.43 1,689 2.83

Nitrogen Phosphorus Volume used

Year (gallons) (total lbs.) (total lbs.)

2005 52,846,100 142 2.73 4,057 6.80 2,117 3.552006 66,693,900 179 3.45 5,121 8.58 2,672 4.482007 81,246,300 218 4.20 6,238 10.50 3,255 5.452008 68,599,300 184 3.55 5,267 8.83 2,748 4.602009 42,167,900 113 2.18 3,238 5.43 1,689 2.83

1180 lbs 31 lbsFertilizer 2009

Average Rainfall 48.9 in Estimated irrigation need 20-35 in

Sediment Phosphorus Concentration

Sediment Phosphorus Concentration

(Mean and Range)

0

2000

4000

6000

8000

10000

12000

5 8 18a 2 19 20 6 7 17 1 3 4 28 W6

Pond Number

Ph

osp

ho

rou

s C

on

cen

trat

ion

, m

g/k

g

Sediment Phosphorous Inputs

Water Extractable Phosphorus Concentration (Mean and Range)

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

5 8 18a 2 19 20 6 7 17 1 3 4 28 W6

Pond Number

Ph

osp

ho

rou

s C

on

cen

trat

ion

, mg

/kg

Sediment Copper

Concentration

Sediment Total Copper Concentration

(Mean and Range)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

5 8 18a 2 19 20 6 7 17 1 3 4 28 W6

Pond Number

Co

pp

er C

on

cen

trat

ion

, mg

/kg

AET 1,300

AET 390

Source of Copper in Sediment

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000C

uS

O4

/OM

-10 0 10 20 30 40 50 60 70

Copper treatments 2006-2009

To

tal

Co

pp

er/O

M

R2 0.83

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.

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

Floating Treatment Wetland?

Beemats, - New Smyrna Beach, FLACF Inc., Jacksonville, FLHidrolution, Spain

PositiveLikely improve water quality, suppress SAV, algae Avoids homeowner shoreline

UncertaintiesTreatment efficiencies unknownNo direct suppression of filamentous algae along littoral shelf Optimization (harvesting) unknown