How Watershed Management and Land-Use affect Water Production in Utah? Ibrahim N. Mohammed David G. Tarboton Utah Water Research Laboratory, Utah State University
[email protected]
Overview Impacts of LandUse Changes on water Production. Water Input? Natural Runoff? 12 Watersheds in The State of Utah (HUC 8).
Long Time Scale Water Balance
P E
∆S=P-Q-E P=Q+E Q=P-E
∆S (Milly, 1994)
Q
Regional Studies of Climate and the Water Balance...
P=Q+E E=P
E Q
E=Ep
E
P (Budyko, 1979)
Long Time Scale Water Balance and Runoff 2.0
2.0
Q=P-E 1.5
Reducing Retention
1.0
Q/Ep
1.0
(Budyko, 1979)
0.5
0.5
0.0
0.0
E/Ep
1.5
Reducing Retention
0.0
0.5
1.0
1.5
2.0
0.0
P/Ep
0.5
1.0
1.5
2.0
P/Ep
• Ep/P is an index of dryness, • Reduced retention increases runoff (deforestation), • Imperviousness increases runoff, • Variability in Q due to differences between large numbers, P-E • Greater relative sensitivity in arid areas.
Hamlet, A. F., and D. P. Lettenmaier. 2005. Production of temporally consistent gridded precipitation and temperature fields for the continental united states. Journal of Hydrometeorology 6(3): 330 336. Oregon
Idaho
South Dakota Wyoming
Nevada Utah Colorado
California
Precipitation, Air Temp., Wind speed
Oklahoma Arizona
N
0
150
300 Kilometers
New Mexico
600
Texas
Daily Gridded Great Basin & Colorado datasets, 1/8 - degree resolution.
Streamflow... (USGS-HCDN)
Idaho ! !
!
Wyoming
! !
Nevada
Hydro-Climatic Data Network
Utah
!
!
!
Bear River near UT-WY state line
N
!
0
100
!
200
0.6
!
Kilometers
0.5
!!
Colorado !
!
0.4
! !
Arizona
0.3
Escalante Desert Upper Sevier
0.2
Q/A (m)
!
Upper Bear Upper Virgin 1940
1950
1960
1970
1980
1990
!
2000
0
0
15 Kilometers
30
5
10
Kilometers
A= 2450 km2
Duchesne
A= 450 km2
Land Use... Watershed Attributes
http://earth.gis.usu.edu/index.html
http://www.gis.usu.edu/ Land cover information from NLCD seamless Data map http://seamless.usgs.gov/website/seamless/viewer.php
Evaporation.... Potential Evaporation http://eos-webster.sr.unh.edu/data_guides/ghaas_usa_dg.jsp
Runoff Ratio = Q/(AP) 0.145
(1997-2001) ~
0.101
60
LOWESS
50
(R default)
40
A= 2450 km2
% (Area)
1992
1993
2001
30
1995 1998
0.08
0.12
(1992-1996) ~
Upper Virgin at Virgin
20 10 0
Water/Wetland
1994 0.04
Q/A (m)
0.16
Land-Use Effect
1996 2000 0.3
0.4
1992 0.5
Range
1997
0.6
Precipitation (m)
0.7
Agriculture
Urban Forest
On Going Tasks... Examining
Trends in Water Balance Quantities... (Precipitation, Evaporation, Runoff) Quantifying Natural Runoff Changes, Analysis of Relationships and Trends.
Results & Their Benefits.... Quantification of The General Sensitivity of Water Availability at The Scale of Regional Subbasins to Changes In LandUse and Watershed Management (index of dryness). Guidance to Water Resources Management In State Of Utah. Linkage to Other Studies (Economics).
