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Overland Parameters
| [show]TABLE 17.17 Adjustment for the Erodibility Factor (K) |
|---|
- For soils with high very fine sand content of greater than 15%
- For soil textures coarser than loam (represented by the shaded area in the nomograph), subtract 5% from the percentage of verv fine sand and add the difference to the silt content. The 5% remaining very tine sand should be added to the % total sand"
- For soil textures finer than loam (represented by the areas outside of the shaded area in the nomograph), subtract 10% from the % very fine sand and add the differenct to the silt content. The 10 % remaining very fine sand should be added to the % total sand.
- Determine the K value from the nomograph using the corrected sand and silt contents
- For soil conditions outside the ideal conditions used to develop the nomograph as follows:
- If organic matter content is different from 2%, add the correction values provided in the following table
| |
Correction values when organic matter is
|
| K value |
0% |
1% |
2% |
3% |
4% |
|
| Greater than 0.40 |
+0.14 |
+0.07 |
0.00 |
-0.07 |
-0.14 |
| 0.20-0.40 |
+0.10 |
+0.05 |
0.00 |
-0.05 |
-0.10 |
| Less than 0.20 |
+0.06 |
+0.03 |
0.00 |
-0.03 |
-0.06 |
- if rock content greater than 15%. the following table is used to adjuSt the K values. Rock content is the amount of soil particles by volume greater than 2.0 mm.
| |
Correction values when rock content is about
|
| K value |
15-35% |
35-60% |
60-75% |
|
| 0.10 |
+0.06 |
+0.05 |
+0.02 |
| 0.15 |
+0.10 |
+0.05 |
+0.02 |
| 0.17 |
+0.10 |
+0.05 |
+0.02 |
| 0.20 |
+0.10 |
+0.05 |
+0.02 |
| 0.24 |
+0.15 |
+0.10 |
+0.05 |
| 0.28 |
+0.15 |
+0.10 |
+0.05 |
| 0.32 |
+0.17 |
+0.10 |
+0.05 |
| 0.37 |
+0.20 |
+0.10 |
+0.05 |
| 0.43 |
+0.24 |
+0.15 |
+O.1O |
| 0.49 |
+0 28 |
+0.15 |
+0.10 |
| 0.55 |
+0.32 |
+0.17 |
+0.10 |
| 0.64 |
+0.37 |
+0.20 |
+0.15 |
- if soil structures are disturbed the following corrections are added to the K values.
| Soil structure |
Corrections |
|
| Very fine granular |
-0.09 |
|
| Fine granular |
-0.06 |
| Moderate or coarse granular |
-0.03 |
- K corrections for permeability are provided as follows:
| Soil characteristics |
Corrections |
|
| Compact soil or pH greater than 9.0 |
+ 0.03 |
| Many medium or coarse pores |
-0.03 |
|
Source: From Goldman et al. (1986).
[show]TABLE 17.18 Cropping Management Factor (C) Values for Various Types of Cover
|
| Type of cover |
C |
Reduction, %
|
| None (fallow ground) |
1.00 |
0
|
| Native Vegetation (undisturbed) |
0.01 |
99
|
| Temporary Seedings (90% stand)—after 60 days |
0.10 |
90
|
| 90% cover, annual grasses, no mulch
|
| Wood liber mulch, 0.75 ton/acre, with seed |
0.50 |
50
|
| Ryegrass (perennial type) |
0.05 |
95
|
| Ryegrass (annulus) |
0.10 |
90
|
| Millet or Sudan Grass |
0.05 |
95
|
| Small Grain |
0.05 |
95
|
| Permanent Seedings (90% stand)
|
| First 60 days |
0.40 |
60
|
| 60 to 365 days |
0.05 |
95
|
| After 365 days |
0.01 |
99
|
| Sod (laid immediately) |
0.01 |
99
|
| Mulch (rate of application in tons/ac)
|
| Hay at 0.5 ton/ac |
0.25 |
75
|
| Hay at 1.0 ton/ac |
0.13 |
87
|
| Hay at 1.5 tons/ac |
0.07 |
93
|
| Hay at 2.0 tons/ac |
0.02 |
98
|
| Small Grain Straw at 2.00 tons/ac |
0.02 |
98
|
| Straw at 1.5 tons/ac, tacked down (for slopes up to 2:1) |
0.20 |
80
|
| Straw at 4.0 tons/ac, tacked down (for slopes up to 2:1) |
0.05 |
95
|
| Wood Chips at 6.0 tons/ac |
0.06 |
94
|
| Wood Cellulose at 1.75 tons/ac |
0.10 |
90
|
| Fiberglass at 0.5 ton/ac |
0.05 |
95
|
| Asphalt Emulsion (1250 gal/ac) |
0.02 |
98
|
| Excelsior mat, jute (for slopes up to 2:1) |
0.30 |
70
|
Unit conversion: 1 ton/ac = 2.267 t/ha.
Sources: From Wanielista, 1978 and Goldman et ai. (1986).
|
[show]TABLE 17.19 Cropping Management Factor (C)
for General Land Use
|
| General land use |
C
|
| Crop Land |
0.08
|
| Pasture Land |
0.01
|
| Forest Land |
0.005
|
| Urban Land |
0.01
|
| Other |
1.00
|
Source: Wanielista (1978).
[show]TABLE 17.22 Erosion Control Practice Factors for Construction Sites
|
| Surface condition |
P
|
| Compacted and smooth |
1.3
|
| Trackwalked along contour1 |
1.2
|
| Trackwalked up and down slope2 |
0.9
|
| Punched straw |
0.9
|
| Rough, irregular cut |
0.9
|
| Loose to 12-in (30-cm) depth |
0.8
|
1Tread marks oriented up and down slope
2Tread marks oriented parallel to contours.
Source: From Goldman et al. (1986)
| [show]Overland Roughness Table
|
| Land Use or Cover |
Recommended n-Value |
Range
|
| Concrete or asphalt |
0.011a |
0.01-0.013a
|
| Developed/industrial |
0.0137b |
-
|
| Bare sand |
0.01a |
0.010-0.016a
|
| Graveled surface |
0.02a |
0.012-0.03a
|
| Bare clay-loam (eroded) |
0.02a |
0.012-0.033a
|
| Gullied land |
- |
0.320-0.357c
|
| Bare field - no residue |
0.05a |
0.006-0.16a
|
| Range (natural) |
0.13a |
0.01-0.32a
|
| Range (clipped) |
0.10a |
0.02-0.24a
|
| Grass and pasture |
- |
0.05-0.15a
|
| Pasture |
- |
0.235-271c
|
| Clover |
- |
0.08-0.25a
|
| Small grain |
- |
0.1 -0.4a
|
| Row crops |
- |
0.07-0.2a
|
| Cotton/soy |
- |
0.246-0.261c
|
| Grass (bluegrass sod) |
0.45a |
0.39-0.63a
|
| Short grass prairie |
0.15a |
0.10-0.203
|
| Dense grass |
0.24a |
0.17-0.30a
|
| Bermuda grass |
0.41a |
0.30-0.48a
|
| Forest |
0.192b |
0.184-198c
|
| Sparely vegetated |
0.150b |
-
|
aEngman (1986), bDowner, cSenarath et al (2000)
|
Stream Parameters
Table 12.2.1 Variation of Manning's Roughness Coefficients n with Bed Type
| [show]Bed characteristics |
Reference Manning's roughness coefficient n
|
| Sand:
|
| Plane bed |
0.011-0.020
|
| Ripple bed |
0.018-0.035
|
| Dune bed |
0.020-0.035
|
| Standing waves |
0.014-0.025
|
| Antidunes |
0.015-0.035
|
| Gravel and cobbles: |
0.020-0.030
|
| Boulder |
"Roughness varies greatly. Usually roughness increases
with decreasing flow depth, n can reach 0.1"
|
| Vegetation |
"Roughness varies greatly with the changes of density,
height, flexibility of vegetation, and the relative ratio
between flow depth and vegetative elements"
|
| "Bermuda, Kentucky, Buffalo grasses" |
Flow depth more than 5 times vegetation height
n between 0.03 and 0.06
|
Flow depth the same or less than that of
vegetation height. 0.01-0.2
|
| Extremely dense vegetation |
"Vegetation height above flow depth, n can exceed 1"
|
| Natural sandy streams:
|
| Clean and straight |
0.025-0.04
|
| Winding and some weeds |
0.03-0.05
|
| Mountain streams with boulders |
0.04-0.1
|
| align="center" | Floodplains:
|
| Short grass |
0.02-0.04
|
| High grass |
0.03-0.05
|
| Dense willow, brush, etc. |
0.05-0.20
|
[show]Table of Particle Classifications
|
| |
Size, mm |
μm |
Inches |
Tyler |
US. standard |
Class
|
|
| Boulders and cobbles:
|
| |
4000-2000 |
|
|
160-80 |
|
|
Very large boulders
|
| |
2000-1000 |
|
|
80-40 |
|
|
Large boulders
|
| |
1000-500 |
|
|
40-20 |
|
|
Medium boulders
|
| |
500-250 |
|
|
20-10 |
|
|
Small boulders
|
| |
250-130 |
|
|
10-5 |
|
|
Large cobbles
|
| |
130-64 |
|
|
5-2.5 |
|
|
Small cobbles
|
| Gravel:
|
| |
64-32 |
|
|
2.5-1.3 |
|
|
Very coarse gravel
|
| |
32-16 |
|
|
1.3-0.6 |
|
|
Coarse gravel
|
| |
16-8 |
|
|
0.6-0.3 |
2 1/2 |
|
Medium gravel
|
| |
8-4 |
|
|
0.3-0.16 |
5 |
5 |
Fine gravel
|
| |
4-2 |
|
|
0.16-0.08 |
9 |
10 |
Very fine gravel
|
| Sand:
|
| |
2-1 |
2.00-1.00 |
2000-1000 |
|
16 |
18 |
Very coarse sand
|
| |
1-11/2 |
1.00-0.50 |
1000-500 |
|
32 |
35 |
Coarse sand
|
| |
1/2-1/4 |
0.50-0.25 |
500-250 |
|
60 |
60 |
Medium sand
|
| |
1/4-1/8 |
0.25-0.125 |
250-125 |
|
115 |
120 |
Fine sand
|
| |
1/8-1/16 |
0.125-0.062 |
125-62 |
|
250 |
230 |
Very fine sand
|
| Silt:
|
| |
1/16-1/32 |
0.062-0.031 |
62-31 |
|
|
|
Coarse silt
|
| |
1/32-1/64 |
0.031-0.016 |
31-16 |
|
|
|
Medium silt
|
| |
1/64-1/128 |
0.016-0.008 |
16-8 |
|
|
|
Fine silt
|
| |
1/128-1/256 |
0.008-0.004 |
8-4 |
|
|
|
Very fine silt
|
| Clay:
|
| |
1/256-1/512 |
0.004-0.0020 |
4-2 |
|
|
|
Coarse clay
|
| |
1/512-1/1024 |
0.0020-0.0010 |
2-1 |
|
|
|
Medium clay
|
| |
1/1024-1/2048 |
0.0010-0.0005 |
1-0.5 |
|
|
|
Fine clay
|
| |
1/2048-1/4096 |
0.0005-0.00024 |
0.5-0.24 |
|
|
|
Very fine clay
|
|
Source: From Lane.78
|
Culvert & Weir Parameters
| [show]Table 48. Values of C in the Formula Q = CLH3/2 for Models of Broad-crested Weirs with Rounded Upstream Corner
|
Name of
Experimenter
|
|
|
|
Head in feet, H
|
| 0.4 |
0.6 |
0.8 |
1.0 |
1.5 |
2.0 |
2.5 |
3.0 |
4.0 |
5.0
|
| Bazin |
0.33 |
2.62 |
2.46 |
2.93 |
2.97 |
2.98 |
3.01 |
3.04 |
|
|
|
|
|
| Bazin |
0.33 |
6.56 |
2.46 |
2.70 |
2.82 |
2.87 |
2.89 |
2.92 |
|
|
|
|
|
| U.S. Deep Waterways |
0.33 |
2.52 |
4.57 |
|
2.77 |
2.8 |
2.83 |
2.92 |
3 |
3.08 |
3.17 |
3.34 |
3.5
|
| U.S. Deep Waterways |
1.33 |
6.56 |
4.56 |
|
|
2.83 |
2.83 |
2.83 |
2.82 |
2.82 |
2.82 |
2.82 |
2.81
|
|
| [show]Table 49. Values of C in the Formula Q = CLH3/2 for Broad-Crested Weirs with Crests Inclined Slightly Downward
|
| Slope of Crest
|
Length
of weir
in feet
|
Head in feet, H
|
| 0.1 |
0.2 |
0.3 |
0.4 |
0.5 |
0.6 |
0.7
|
| 12 to 1 |
3.0 |
2.58 |
2.87 |
2.57 |
2.60 |
2.84 |
2.81 |
2.70
|
| 18 to 1 |
3.0 |
2.91 |
2.92 |
2.53 |
2.60 |
2.80 |
2.74 |
2.62
|
| 18 to 1 |
10.0 |
2.52 |
2.68 |
2.73 |
2.80 |
2.90 |
2.80 |
2.68
|
|
| [show]Table 50. Values of C in the Formula Q = CLH3/2 for weirs of Triangular Cross Section with Vertical Upstream Face and Sloping Downstream Face
|
Slope of
down-
stream
face
|
Height
of weir
in feet,
P
|
Head in feet, H
|
| 0.2 |
0.3 |
0.4 |
0.5 |
0.6 |
0.7 |
0.8 |
0.9 |
1.0 |
1.2 |
1.5
|
| Hor. Vert. |
|
|
|
|
|
|
|
|
|
|
|
|
| 1 to 1 |
2.46 |
3.88 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85 |
3.85
|
| 2 to 1 |
2.46 |
3.48 |
3.48 |
3.49 |
3.49 |
3.5 |
3.5 |
3.5 |
3.5 |
3.5 |
3.51 |
3.51
|
| 2 to 1 |
1.64 |
3.56 |
3.47 |
3.47 |
3.51 |
3.54 |
3.57 |
3.58 |
3.58 |
3.58 |
3.59 |
3.57
|
| 3 to 1 |
1.64 |
|
2.9 |
3.11 |
3.22 |
3.26 |
3.33 |
3.37 |
3.4 |
3.4 |
3.41 |
3.41
|
| 5 to 1 |
2.46 |
|
3.08 |
3.06 |
3.05 |
3.05 |
3.07 |
3.09 |
3.12 |
3.13 |
3.13 |
3.18
|
| 10 to 1 |
2.46 |
|
2.82 |
2.83 |
2.84 |
2.86 |
2.89 |
2.9 |
2.91 |
2.91 |
2.92 |
2.93
|
|
Infiltration Process Parameters
| [show]RICHARDS_EQN_INFILTRATION_BROOKS Parameters
|
| Table Name |
# Values |
Parameter |
Units |
Typical Range
|
RICHARDS_EQN_INFILTRATION_BROOKS
3 sets of values for each ID.
one set of values per line for each soil layer |
9x3 |
Ks |
cm/hr |
0.05 - 23.5
|
| e |
none |
0.4 - 0.55
|
| θr |
none |
0.01 -0.1
|
| θi |
none |
θr - e
|
| θwp |
none |
0.03 - 0.25
|
| d |
cm |
NA
|
| λ |
none |
0.1 - 0.4
|
| Ψb |
cm |
5.0 - 100.0
|
| Δz |
cm |
0.1 - 10.0
|
| [show]RICHARDS_EQN_INFILTRATION_HAVERCAMP Parameters
|
| Table Name |
# Values |
Parameter |
Units |
Range
|
RICHARDS_EQN_INFILTRATION_HAVERCAMP
3 sets of values for each ID
One set of values per line for each soil layer |
11 x 3 |
Ks |
cm/hr |
0.05 - 23.5
|
| e |
none |
0.4 - 0.55
|
| θr |
none |
0.01 -0.1
|
| θi |
none |
θr - e
|
| θwp |
none |
0.03 - 0.25
|
| dL |
cm |
NA
|
| α |
none |
fit to curve
|
| Β |
none |
fit to curve
|
| A |
none |
fit to curve
|
| B |
none |
fit to curve
|
| Δz |
cm |
0.1 - 10.0
|
Evapotranspiration Parameters
| [show]Table A.l: Albedos of shortwave radiation for assorted types of vegetation/land-cover typesa
|
| Ground Cover |
Albedo
|
| Snow |
see Figures A.l and A.2
|
| Fresh snow |
0.75-0.95b, 0.70-0.95c, 0.80-0.95d, 0.95e
|
| Fresh snow (low density) |
0.85f
|
| Fresh snow (high density) |
0.65f
|
| Fresh dry snow |
0.80-0.95g
|
| Pure white snow |
0.60-0.70g
|
| Polluted snow |
0.40-0.50g
|
| Snow several days old |
0.40-0.70b, 0.70c, 0.42-0.70d, 0.40e
|
| Clean old snow |
0.55f
|
| Dirty old snow |
0.45f
|
| Clean glacier ice |
0.35f
|
| Dirty glacier ice |
0.25f
|
| Glacier |
0.20-0.40e
|
| Dark soil |
0.05-0.15b, 0.05-0.15g
|
| Dry clay or gray soil |
0.20-0.35b, 0.20-0.35g
|
| Dark organic soils |
O.10f
|
| Dry black soil |
0.14i
|
| Moist black soil |
0.08i
|
| Dry gray soils |
0.25-0.30i
|
| Moist gray soils |
0.10-0.20g, 0.10-0.12i
|
| Dry blue loam |
0.23i
|
| Moist blue loam |
0.16i
|
| Desert loam |
0.29-0.31i
|
| Clay |
0.20f
|
| Dry clay soils |
0.20-0.35d
|
| Dry light sand |
0.25-0.45b
|
| Dry, light sandy soils |
0.25-0.45g
|
| Dry, sandy soils |
0.25-0.45d
|
| Light sandy soils |
0.35f
|
| Dry sand dune |
0.35-0.45b, 0.37c
|
| Wet sand dune |
0.20-0.30b, 0.24c
|
| Dry light sand, high sun |
0.35f
|
| Dry light sand, low sun |
0.60f
|
| Wet gray sand |
0.10f
|
| Dry gray sand |
0.20f
|
| Wet white sand |
0.25f
|
| Dry white sand |
0.35f
|
| Yellow sand |
0.35f
|
| White sand |
0.34-40i
|
| River sand |
0.43i
|
| Bright, fine sand |
0.37i
|
| Rock |
0.12-0.15i
|
| Peat soils |
0.05-0.15d
|
| Dry black coal spoil, high sun |
0.05f
|
| Dry concrete |
0.17-0.27b, 0.10-0.35e
|
| Road black top |
0.05-0.10b
|
| Ground Cover |
Albedo
|
| Asphalt |
0.05-0.20e
|
| Tar and gravel |
0.08-0.18e
|
| Densely urbanized areas |
0.15-0.25i
|
| Urban area |
0.10-0.27 with an average of 0.15e
|
| Long grass (1.0 m) |
0.16e
|
| Short grass (2 cm) |
0.26e
|
| Wet dead grass |
0.20f
|
| Dry dead grass |
0.30f
|
| High, dense grass |
0.18-0.20i
|
| Green grass |
0.26i
|
| Grass dried in sun |
0.19i
|
| Typical fields |
0.20f
|
| Dry steppe |
0.25f, 0.20-0.30g
|
| Tundra and heather |
0.15f
|
| Tundra |
0.18-0.25e, 0.15-0.20g
|
| Heather |
0.10i
|
| Meadows |
0.15-0.25g
|
| Cereal and tobacco crops |
0.25f
|
| Cotton, potatoes and tomato crops |
0.20f
|
| Cotton |
0.20-0.22i
|
| Cotton plantations |
0.20-0.25g
|
| Potatoes |
0.19i
|
| Potato plantations |
0.15-0.25g
|
| Lettuce |
0.22i
|
| Beets |
0.18i
|
| Sugar cane |
0.15f
|
| Orchards |
0.15-0.20e
|
| Agricultural crops |
0.18-0.25e, 0.20-0.30d
|
| Rice field |
0.12i
|
| Rye and wheat fields |
0.10-0.25g
|
| Spring wheat |
0.10-0.25i
|
| Winter wheat |
0.16-0.23i
|
| Winter rye |
0.18-0.23i
|
| Deciduous forests - bare of leaves |
0.15e
|
| Deciduous forests - leaved |
0.20e
|
| Deciduous forests |
0.15-0.20g
|
| Deciduous forests - bare with snow on the ground |
0.20d
|
| Mixed hardwoods in leaf |
0.18f
|
| Rain forest |
0.15f
|
| Eucalyptus |
0.20f
|
| Forest - pine, fir, oak |
0.10-0.18c
|
| Forest - coniferous forests |
0.10-0.15g, 0.10-0.15d
|
| Forest - red pine forests |
0.10f
|
| Tops of oak |
0.18i
|
| Tops of pine |
0.14i
|
| Tops of fir |
0.10i
|
| Water |
-0.0139 + 0.0467 tan Z, 1 ≥ A ≥ 0.03h
|
| Water |
see Figure A.3
|
NOTE:- aThe smaller value is for high zenith angles; larger value for low zenith angles.
From b Sellers (1965); c Munn (1966); d Rosenberg (1974); e Oke (1973); f Lee (1978); g de Jong (1973); h Atwater and Ball (1981); and, i Eagleson (1970).
[show]Table A.2: Typical Extinction of Insolation by Grass
(adapted from Eagleson. 1970)
|
| Height of Grass (cm) |
Kt
|
| 100 |
0.18
|
| 50 |
0.18
|
| 10 |
0.68
|
Source: Data from O.G. Sutton, "Micrometeorology," McGraw-Hill, New York, 1953.
|
| [show]Table A.3: Typical values of canopy resistance at noon
|
| Type of Vegetation |
Canopy Resistance at Noon (s/m)
|
| Cotton fielda |
~ 17
|
| Coniferous forest (Spruce)a |
~ 100
|
| Coniferous forest (Hemlock)a |
~ 150
|
| Coniferous forest (Pine, March)b |
~ 140
|
| Coniferous forest (Pine, June)b |
~ 120
|
| Coniferous forest (Pine, September/October)b |
~ 123
|
| Prairie grasslands (late July)c |
~ 100
|
| Prairie grasslands (mid September)c |
-500
|
| Irrigated short grass cropd |
-86
|
| Unirrigated barleyd |
-43
|
from aPielke (1984), bGash and Stewart (1975), cMonteith (1975) and dSceicz and Long (1969)
|
| [show]Table A.5: Sample values of vegetation height (Eagleson, 1970)
|
| Vegetation/Forest Types |
Sample Vegetation Height (cm)
|
| Mown Grass |
1.5-4.5
|
| Alfalfa |
20 - 40
|
| Long Grass |
60-70
|
| Maize |
90-300
|
| Sugar Cane |
100-400
|
| Brush |
135
|
| Orange Orchard |
350
|
| Pine forest |
500 - 2700
|
| Deciduous forest |
1700
|
NOTE: The vegetation heights listed in Table A.3 are sample values only. Those values may not be the representative, expected vegetation height-values of those vegetation/forest types.
|
TABLE D-2
[show]Visible-Range Reflectance (albedo) of
Various Forms of Water and Various Earth Materials
|
| Surface |
Conditions |
Albedo, a
|
| Clouds |
Low overcast: |
100 m thick |
0.40
|
| |
|
200 m thick |
0.50
|
| |
|
500 m thick |
0.70
|
| Liquid water |
Smooth; solar angle: |
60° |
0.05
|
| |
|
30° |
0.10
|
| |
|
20° |
0.15
|
| |
|
10° |
0.35
|
| |
|
5° |
0.60
|
| |
Wavy; solar angle: |
60° |
0.10
|
| Solid water |
Fresh snow; |
low density |
0.85
|
| |
|
high density |
0.65
|
| |
Old snow; |
clean |
0.55
|
| |
|
dirty |
0.45
|
| |
Glacier ice; |
clean |
0.35
|
| |
|
dirty |
0.25
|
| Sand |
Dry, light; |
high sun |
0.35
|
| |
|
low sun |
0.60
|
| |
Gray; |
wet |
0.10
|
| |
|
dry |
0.20
|
| |
White; |
wet |
0.25
|
| |
|
dry |
0.35
|
| Soil |
Organic; |
dark |
0.10
|
| |
Clay |
|
0.20
|
| |
Sandy; |
light |
0.30
|
| Grass |
Typical fields |
|
0.20
|
| |
Dead; |
wet |
0.20
|
| |
|
dry |
0.30
|
| Tundra, heather |
|
|
0.15
|
| Crops |
Cereals, tobacco |
|
0.25
|
| |
Cotton, potato, tomato |
|
0.20
|
| |
Sugar cane |
|
0.15
|
| Trees |
Rain forest |
|
0.15
|
| |
Eucalyptus |
|
0.20
|
| |
Red pine forest |
|
0.10
|
| |
Mixed hardwoods in leaf |
|
0.18
|
Data from Lee (1980).
Soil and Groundwater Parameters
| [show]TABLE 12.1.2 Porosity and Specific Weight for Sediments
|
Classification and range
mm
|
Fine sand
1/8-1/4 mm
|
Fine sand
1/4-1/2 mm
|
Medium sand
1/2-1 mm
|
Coarse sand
1-2 mm
|
Coarse sand
2-4 mm
|
Gravelly sand
4-8 mm
|
Fine gravel
8-16 mm
|
Medium gravel
16-32 mm
|
Coarse gravel
32-64 mm
|
Coarse gravel
64-128 mm
|
Coarse gravel
and boulders
128-256 mm
|
| Porosity, % |
44 |
43 |
41 |
39 |
37.5 |
34.5 |
33 |
27 |
23 |
18 |
17
|
Specific weight
kN/m3 |
14 |
15 |
15 |
16 |
16 |
17 |
18 |
19 |
20 |
22 |
22
|
Specific weight
lb f/ft3 |
93 |
94 |
98 |
101 |
103 |
108 |
111 |
121 |
127 |
130 |
137
|
|
[show] Table 6. Specific Storage
(Anderson & Woessner, 1992).
|
| Material |
Specific storage (Ss)/(m)
|
| Plastic Clay |
2.0E-02 to 2.6E-03
|
| Stiff Clay |
2.6E-03 to 1.3E-03
|
| Medium-hard clay |
1.3E-03 to 9.2E-04
|
| Loose sand |
1.0E-03 to 4.9E-04
|
| Dense sand |
2.0E-04 to 1.3E-04
|
| Dense sandy gravel |
1.0E-04 to 4.9E-05
|
| Rock, fissure, jointed |
6.9E-05 to 3.3E-06
|
| Rock, sound |
Less than 3.3e-6
|
|
[show]TABLE 6-1 Representative Values of Parameters in Equations (6-11) and (6-12)
Based on Analysis of 1845 Soilsa
|
| Soil Texture |
Φ |
Khsat
(cm/s) |
|Ψs|
(cm) |
b
|
| Sand |
0.395 (0.056) |
1.76 x 10-2 |
12.1 (14.3) |
4.05 (1.78)
|
| Loamy sand |
0.410 (0.068) |
1.56 x 10-2 |
9.0 (12.4) |
4.38 (1.47)
|
| Sandy loam |
0.435 (0.086) |
3.47 x 10-3 |
21.8 (31.0) |
4.90 (1.75)
|
| Silt loarn |
0.485 (0.059) |
7.20 x 10-4 |
78.6 (51.2) |
5.30 (1.96)
|
| Loam |
0.451 (0.078) |
6.95 x 10-4 |
47.8 (51.2) |
5.39 (1.87)
|
| Sandy clay loam |
0.420 (0.059) |
6.30 x 10-4 |
29.9 (37.8) |
7.12 (2.43)
|
| Silty clay loam |
0.477 (0.057) |
1.70 x 10-4 |
35.6 (37.8) |
7.75 (2.77)
|
| Clay loam |
0.476 (0.053) |
2.45 x 10-4 |
63.0 (51.0) |
8.52 (3.44)
|
| Sandy clay |
0.426 (0.057) |
2.17 x 10-4 |
15.3 (17.3) |
10.4 (1.64)
|
| Silty clay |
0.492 (0.064) |
1.03 x 10-4 |
49.0 (62.1) |
10.4 (4.45)
|
| Clay |
0.482 (0.050) |
1.28 x 10-4 |
40.5 (39.7) |
11.4 (3.70)
|
|
|
a Values in parentheses are standard deviations.
Data from Clapp and Hornberger (1978).
|
| [show]Table 7. Specific Yield (Fetter, 1994).
|
| Material |
Specific Yield (Sy)
|
| Min |
Max |
Average
|
| Clay |
0.00 |
0.05 |
0.02
|
| Sandy clay |
0.03 |
0.12 |
0.07
|
| Silt |
0.03 |
0.19 |
0.18
|
| Fine sand |
0.10 |
0.28 |
0.21
|
| Medium sand |
0.15 |
0.32 |
0.26
|
| Coarse sand |
0.20 |
0.35 |
0.27
|
| Gravelly sand |
0.20 |
0.35 |
0.25
|
| Fine gravel |
0.21 |
0.35 |
0.25
|
| Medium gravel |
0.13 |
0.26 |
0.23
|
| Coarse gravel |
0.12 |
0.26 |
0.22
|
|
| [show]Table 1. Rawls & Brakensiek soil parameter estimates.
|
(1)
USDA
Textural
Classification
|
(2)
Total
Porosity
|
(3)
Effective
Porosity
|
(4)
Residual
Water
Content
|
(5)
Wilting
Point
Water
Content
|
(6)
Air
Entry
Pressure
(cm)
|
(7)
Pore
Distrib.
Index
|
(8)
Sat.
Hydr.
Conduct.
(cm/hr)
|
(9)
G&A
Capillary
Head
(cm)
|
| Sand |
0.437 |
0.417 |
0.020 |
0.033 |
7.26 |
0.694 |
23.56 |
4.95
|
| Loamy sand |
0.437 |
0.401 |
0.035 |
0.055 |
8.69 |
0.553 |
5.98 |
6.13
|
| Sandy loam |
0.453 |
0.412 |
0.041 |
0.095 |
14.66 |
0.378 |
2.18 |
11.01
|
| Loam |
0.463 |
0.434 |
0.027 |
0.117 |
11.15 |
0.252 |
1.32 |
8.89
|
| Silt loam |
0.501 |
0.486 |
0.015 |
0.133 |
20.79 |
0.234 |
0.68 |
16.68
|
| Sandy clay loam |
0.398 |
0.330 |
0.068 |
0.148 |
28.08 |
0.319 |
0.30 |
21.85
|
| Clay loam |
0.464 |
0.390 |
0.075 |
0.197 |
25.89 |
0.242 |
0.20 |
20.88
|
| Silty clay loam |
0.471 |
0.432 |
0.040 |
0.208 |
32.56 |
0.177 |
0.20 |
27.30
|
| Sandy clay |
0.430 |
0.321 |
0.109 |
0.23'9 |
29.17 |
0.223 |
0.12 |
23.90
|
| Silty clay |
0.479 |
0.423 |
0.056 |
0.250 |
34.19 |
0.150 |
0.10 |
29.22
|
| Clay |
0.475 |
0.385 |
0.090 |
0.272 |
37.30 |
0.165 |
0.06 |
31.63
|
|
USDA Soil Properties Calculator
| [show]Field Capacity
|
| Texture Class |
-1 SD |
MEAN |
+1 SD
|
| Sand |
0.018 |
0.091 |
0.164
|
| Loamy Sand |
0.060 |
0.125 |
0.190
|
| Sandy Loam |
0.126 |
0.207 |
0.288
|
| Loam |
0.195 |
0.270 |
0.345
|
| Silt Loam |
0.258 |
0.330 |
0.402
|
| Sandy Clay Loam |
0.186 |
0.255 |
0.324
|
| Clay Loam |
0.250 |
0.318 |
0.386
|
| Silty Clay Loam |
0.304 |
0.366 |
0.428
|
| Sandy Clay |
0.245 |
0.339 |
0.433
|
| Silty Clay |
0.332 |
0.387 |
0.442
|
| Clay |
0.326 |
0.396 |
0.466
|
From:
Handbook of Hydrology, Maidment
which reproduces it from Rawls & Brakensiek, "prediction of soil water properties for hydrologic modeling", Watershed Management in the Eighties, ASCE
Specific Gravity
[show]Table 2.4 Specific Gravity of Common Minerals
|
| Mineral |
Specific gravity, Gs
|
|
|
Quartz
|
2.65
|
|
Kaolinite
|
2.6
|
|
Illite
|
2.8
|
|
Montmorillonite
|
2.65-2.80
|
|
Halloysite
|
2.0-2.55
|
|
Potassium feldspar
|
2.57
|
|
Sodium and calcium feldspar
|
2.62-2.76
|
|
Chlorite
|
2.6-2.9
|
|
Biotite
|
2.8-3.2
|
|
Muscovite
|
2.76-3.1
|
|
Hornblende
|
3.0-3.47
|
|
Limonite
|
3.6-4.0
|
|
Olivine
|
3.27-3.7
|
|
