Soils Data Summary

Stormwater Management: LID Practices | 2

Soil Phosphorus LevelsSoil Phosphorus Levels

Stormwater Management: LID Practices | 3

Average Phosphorus Concentration in Soils by Catchment

0

50

100

150

200

250

A B C D E F G

Catchment

Me

hli

ch

-1 E

xtr

ac

tab

le P

, p

pm

  Catchment Very Low Medium High Very High  

A 33% 0% 56% 11%

B 0% 14% 29% 57%

C 14% 0% 29% 57%

D 0% 40% 20% 40%

E 0% 0% 0% 100%

F 0% 0% 40% 60%

  G 29% 29% 14% 29%  

Grand Haven 13% 10% 27% 50%

0%

10%

20%

30%

40%

50%

60%

Very Low Medium High Very High

Phosphorus Test Level

% o

f so

ils t

este

d

77% of soils tested do not need any phosphorus fertilizer

Stormwater Management: LID Practices | 5

Fill and Soil Quality Fill and Soil Quality

Fill MaterialpH = 7.3

leachable P = 77.7 + 52 ppm

Fill MaterialpH = 7.3

leachable P = 77.7 + 52 ppm

Native SoilpH = 5.0,

leachable P = 1.4 + 0.5 ppm

Native SoilpH = 5.0,

leachable P = 1.4 + 0.5 ppm

Common space landscaped soils pH = 7.3

Mehlich 1 P = 80.9 + 48 ppm

Common space landscaped soils pH = 7.3

Mehlich 1 P = 80.9 + 48 ppm

Residential landscape soils pH = 7.3

Mehlich 1 P = 93.5 + 34 ppm

Residential landscape soils pH = 7.3

Mehlich 1 P = 93.5 + 34 ppm

Stormwater Management: LID Practices | 6

Soil Phosphorus vs. Copper Sulfate Treatments

Soil Phosphorus vs. Copper Sulfate Treatments

Average Soil P Concentration vs. Copper Sulfate Treatments Between 2005-2008 by Catchment

y = 0.1907x + 13.316

R2 = 0.48020

5

10

15

20

25

30

35

40

45

0 20 40 60 80 100 120 140 160

Mehlich 1 Extractable P, ppm

Av

era

ge

nu

mb

er

of

Co

pp

er

Su

lfa

te T

rea

tme

nts

A

G

DB

F

C

E

Stormwater Management: LID Practices | 7

SummarySummary

• Soil phosphorus test indicates most soils do not require phosphorus fertilizer.

• Phosphorus levels in some fill soil are very high and significantly higher than native soil P.

• Soil phosphorus and frequency of copper sulfate treatments are weakly correlated.