The Effect of
Urbanization on Surface
Water Flows
by Matt Harold
A Study of West Houston
“Houston is Los Angeles with the
climate of Calcutta”
Molly Ivins
Urban Sprawl
1973
1992
Buffalo Bayou
Piney Point
Barker
Res.
Beltway 8
Memorial Park
Barkers Reservoir
Barkers Reservoir
y = 3.616x - 6886.5
800
700
Average Discharge (cfs)
600
500
400
300
200
100
0
1940 1950 1960 1970 1980 1990 2000 2010
Time (Year)
Beltway 8
Beltway 8
y = 4.1852x - 7963.2
900
800
Average Discharge (cfs)
700
600
500
400
300
200
100
0
1965 1970 1975 1980 1985 1990 1995 2000 2005 2010
Time (Year)
USGS
Station
Piney Point
Piney Point
y = 5.8786x - 11316
1000
900
800
Average Discharge (cfs)
700
Average Discharge
600
500
400
300
200
100
USGS
0
0
1960
1960 1965
1965 1970
1970 1975
1975 1980
1980 1985
1985 1990
1990 1995
1995 2000
2000 2005 Station
2005 2010
2010
Time (Year)
Time (Year)
Memorial Park
Memorial Park
y = 25.446x - 49408
Average Discharge (cfs)
2500
2000 USGS
1500
1000
Station
500
0
1930 1940 1950 1960 1970 1980 1990 2000 2010
Time (Year)
In 1975 they
stopped
collecting Daily
Discharge data
Average Rainfall
Rainfall
y = 0.1603x - 269.05
80
70
60
Average Rainfall (in)
50
40
30
20
10
0
1930 1940 1950 1960 1970 1980 1990 2000 2010
Time (Year)
Relatively static, but increasing slightly?
Rainfall vs Discharge
Rainfall vs Discharge
Rainfall vs Discharge
70000000000
30000000000
60000000000
25000000000
50000000000
Rainfall
Volume (ft3 )
Volume (ft3)
20000000000 Rainfall
40000000000 Memorial Park
Barker Res
15000000000 Barker Res
30000000000 Beltway
Beltway
10000000000 PineyPiney Point
Point
20000000000
1990 1992 1994 1996 1998 2000 2002 2004
5000000000
10000000000
0 0
1940 1930 1940
1950 1950
1960 19601970 1970 1980
1980 1990
1990 2000
2000 2010 2010
Time (Year)
Time (Year)
Conclusions
Urban development from 1944-2004 has
had a profound impact on regional surface
water discharges
Increased impervious cover bares most of
the blame
Urban expansion is responsible for other
climactic changes
• Heat Island Effect
• Aerosol
• Surface Roughness
Response is behind the curve
References
Rogers, G.O., DeFee, B.B., 2005. Long-
term impact of development on a
watershed: Early indicators of future
problems. Landscape and Urban Planning.
73, 215–233
Pielke Sr. , R.A., Adegoke , J., Beltrán-
Przekurat , A., Hiemstra , C.A., Lin, J.,
Nair , U.S., Niyogi , D., and Nobis, T.E.,
2006. An Overview of Regional Land-Use
and Land-Cover Impacts on Rainfall.
Questions?