3. Terrain Preprocessing
(Arc Hydro)
Surface Analysis
(Spatial Analyst)

4. Terrain Analysis
(TauDEM)
Terrain Preprocessing
(Arc Hydro)

5. Problems
Fire
Snowmelt
Large Rainstorms

7. Roads

8. Roads
Sediment is the number one pollutant in U.S. waterways.

9. Roads in Farmington Canyon

10. Past Debris Flows
Sources:

11. PSIAC Method Pacific Southwest Inter Agency Committee (1968)
Annual Yield = e ^ (.0359 * FR)
FR = Sediment Rating Factor = sum of (9) different factors.

13. Ys=a*[Q*qp]β*K*LS*CP*S
MUSLE Equation
Ys=a*[Q*qp]β*K*LS*CP*S

14. Ys – Total Tons per Event Q – Storm Runoff (acre-ft)
qp – peak runoff (cfs)

15. a,β – storm factors Typical Rain Storm a=95 β=.56 Snow Melt Flood
β=.3

16. K – Soil Erodibility Factor LS – Slope Factor (length and steepness)
CP – Cover and Management Practice Factor
SDR – Sediment Delivery Ratio

17. gs=a[Q*qp]^b*K*LS*CP*SDR
Q = Storm Runoff (acre-ft)
qp= Peak runoff (cfs)
a = 95
b= .56

18. Q=CIA Q=Runoff C=Runoff Coefficient
I=Intensity of rainfall (assume 1 in/hr)
A=Area of Catchment

20. C=.17

21. C=.3

24. q= Accumulation of Catchment
Accumulation of Basin
* Peak Flow

25. Accumulation of Each Catchment

27. Peak Flow For Farmington Canyon

29. K Factor

30. K Factor http://www.iwr.msu.edu/rusle/kfactor.htm
K factor is soil erodibility factor which represents both susceptibility of soil to erosion and the rate of runoff, as measured under the standard unit plot condition. Soils high in clay have low K values, about 0.05 to 0.15, because they resistant to detachment. Coarse textured soils, such as sandy soils, have low K values, about 0.05 to 0.2, because of low runoff even though these soils are easily detached. Medium textured soils, such as the silt loam soils, have a moderate K values, about 0.25 to 0.4, because they are moderately susceptible to detachment and they produce moderate runoff. Soils having a high silt content are most erodible of all soils. They are easily detached; tend to crust and produce high rates of runoff. Values of K for these soils tend to be greater than 0.4.

31. SSURGO No Data Found

32. STATSGO No Data Found

34. Soil Distribution

35. Soil Distribution (cont.)

36. Soil Distribution (cont.)

37. Soil Distribution (cont.)

38. Calculated K Factor Sample # 1 2 3 4 5 K(chart) 0.08 0.09 Sample # 6 7
%<.1
0.9
0.4
0.6
0.7
.1>%>2
59.4
62.1
44.2
41.4
60.3
%OM
Structure
Permeability
K(chart)
0.08
0.09
Sample # 6 7 8 9 10
%<.1
0.7
1.0
2.4
0.9
.1>%>2
51.1
41.5
63.2
53.2
94.6
%OM 4 2
Structure 3
Permeability
K(chart)
.08
0.09
0.08
0.15
0.06
Sample # 11 12 13 14 15
%<.1
1.1
0.8
0.6
1.3
0.9
.1>%>2
76.7
77.0
65.1
60.6
26.2
%OM 4
Structure 3
Permeability 2
K(chart)
0.07
0.08

41. The Value of Cp

42. http://landcover.usgs.gov/classes.asp Land Cover Classes -
Units in Square Miles
11 Water
12 Perennial Ice Snow
21 Low Intensity Residential
22 Hi Intensity Residential
23 Commercial/Industrial/Transportation
31 Bare Rock
32 Quarries/ Mines
33 Transitional
41 Deciduous Forest
42 Evergreen Forest
43 Mixed Forest
51 Shrub land
61 Orchards/ Vineyard
71 Grasslands/Herbaceous
81 Pasture/Hay
82 Row Crops
83 Small Grains
84 Fallow
85 Urban/Recreational Grasses
91 Woody Wetlands
92 Emergent/Herbaceous Wetlands
State/Region Total

43.
Spatial Analyst
(reclassify)

44. Spatial Annalist
(Zonal Statistics)
Exporting the Data

45. http://landcover.usgs.gov/classes.asp Land Cover Classes -
Units in Square Miles
11 Water
12 Perennial Ice Snow
21 Low Intensity Residential
22 Hi Intensity Residential
23 Commercial/Industrial/Transportation
31 Bare Rock
32 Quarries/ Mines
33 Transitional
41 Deciduous Forest
42 Evergreen Forest
43 Mixed Forest
51 Shrub land
61 Orchards/ Vineyard
71 Grasslands/Herbaceous
81 Pasture/Hay
82 Row Crops
83 Small Grains
84 Fallow
85 Urban/Recreational Grasses
91 Woody Wetlands
92 Emergent/Herbaceous Wetlands
State/Region Total

47. Sample of Excel Data GRIDID SHAPE_LENG SHAPE_AREA Area (acres)
MAJORITY
Type of land cover
Cp Value 17 51
Shrubland
0.06 18 34 35 36 39 40 41 42
Evergreen Forest
0.004 43 44 21
Low Intensity Residential
0.24 45
Mixed Forest 47 49

48. Canyon Vegetation

49. Wattles and sediment diversion and filtration techniques

50. Vegetation in Farmington Canyon

51. Catchment GridID

52. Cross Section
Found Using 3-D Analyst

53. Accounts for length and Steepness of the Slopes
LS Factor
Accounts for length and Steepness of the Slopes

54. Slope of Watershed

55. Mean Slope of Catchments Using zonal Statistics

56. LS Factor LS=(l/72.6)m((430sin2θ+30sinθ+0.43)/6.613)) Where
m =.5 Slope >5%
l = slope length (ft)
θ = slope Angle Degree

57. LS Factor Maximum = 185.7 Mean = 94.8 Minimum = 13.7
St. Deviation= 39.8

58. SDR Factor Sediment Delivery Ratio For low slope watersheds
SDR=(0.001/A)0.2
Farmington Canyon is not low Slope
Assumed to be 1 because all the sediment is removed from the canyon.

59. Assumptions for MUSLE SDR is Equal to 1 Rainfall Event
1inch rainstorm over a 6-hr period.
q=1.5Q
Snowmelt Flood
Used Peak Flow from Flood of 1983

60. Assumptions Continued
Collected K values represented entire watershed.
LP was based on average slope that was uniform.
The majority land cover represented the CP value for entire catchment.

61. Example Spreadsheet for MUSLE Calculation
Snowmelt Flood
Rainfall Event LS K CP Q q
Total Sediment
(acre-ft)
(cfs)
(tons/event)
124.5
0.09
0.06
46.06
15.23
576.19
13.51
40.88
74.3
38.48
12.72
308.68
11.29
34.15
143.5
0.08
16.72
5.53
321.25
4.91
14.84
722.01

62. Rain Event Yield

63. Snowmelt Flood Yield

64. Final Numbers Sediment yield for Snowmelt Flood 10373 tons
Sediment yield for 1-inch rainstorm over 6 hour interval
8539 tons