Soil Parameter Estimates

Texture class

Percent by weight

Suction head

Conductivity

Initial deficit

Porosity

Field capacity

Wilting point

Sand

Clay

in

mm

in/h

mm/h

Sand

88

5

1.9

49.5

4.26

108.1

0.34

0.46

0.10

0.05

Loamy sand

80

5

2.4

61.3

3.81

96.7

0.46

0.12

0.05

Sandy loam

65

10

4.3

110.1

1.98

50.3

0.33

0.45

0.18

0.08

Loam

40

20

3.5

88.9

0.61

15.5

0.31

0.46

0.28

0.14

Silt loam

20

15

6.6

166.8

0.63

16.1

0.32

0.48

0.31

0.11

Silt

10

5

0.87

22

0.48

0.30

0.06

Sandy clay loam

60

25

8.6

218.5

0.44

11.3

0.26

0.43

0.27

0.17

Clay loam

30

35

8.2

208.8

0.17

4.3

0.24

0.48

0.36

0.22

Silty clay loam

10

35

10.7

273.0

0.22

5.7

0.51

0.38

0.22

Silty clay

10

45

11.5

292.2

0.15

3.7

0.52

0.41

0.27

Sandy clay

50

40

9.4

239.0

0.06

1.4

0.44

0.36

0.25

Clay

25

50

12.5

316.3

0.04

1.1

0.21

0.50

0.42

0.30


Sources:

1.      Composition, conductivity, porosity, field capacity, wilting point: Saxton and Rawls, Soil Water Characteristic Estimates by Texture and Organic Matter for Hydrologic Solutions, Soil Sci. Soc. Am. J. 70:1569–1578 (2006). https://www.atmos.illinois.edu/~sshu3/model/saxton2006.pdf

2.      Suction head: Rawls, Brakensiek, and Miller, Green‐Ampt Infiltration Parameters from Soils Data, Journal of Hydraulic Engineering, 109:1 (1983). http://dx.doi.org/10.1061/(ASCE)0733-9429(1983)109:1(62)

3.      Initial deficit: SWMM 4 manual, p. 112.