The Effect of Urbanization to the surface-water runoff

1
The Effect of Urbanization to the surface-water
runoff

• The comparison between the urbanized and
  undeveloped zones

2
Outline

• Objective/Study area
• Data Sources
• Backgrounds
• Map Creation
• Analysis
• Question

3
Objective

1. Build a Basemap of the City of Austin
2. Apply the precipitation data (time-series) on
   the study areas
3. Compare the flow pattern in regards to the land
   cover

4
Study Areas
The Shoal Creek
The Barton Creek
5
Data Sources
1. Aerial Photo Texas Natural Resources
Information http//www.tnris.state.tx.us/update3
.cfm?Tx_County_NameTravis 2. Land Cover
National Land Cover Institute http//landcover.usg
s.gov 3. Digital Elevation Model USGS
Dataset http//seamless.usgs.gov 4. Gage
station data USGS Dataset http//water.usgs.gov/G
IS/metadata/usgswrd/XML/streamgages.xml 5.
Stream Network data City of Austin GIS Data Sets
ftp//coageoid01.ci.austin.tx.us/GIS-Data/Regional
/coa_gis.html 6. Precipitation Data
Hourly/Daily Rain Data from NOAAs Forecast
Systems http//precip.fsl.noaa.gov/hourly_precip
.html
6
Background

• The sources of flooding in Austin area
• Unique geographic and atmospheric condition
• Creeks
• Urban flooding
• Hurricane and tropical storms

7
The Land Cover of Austin, Texas
8
Building a Basemap
Watershed of both creeks
9
The completed Basemap
10
Gathering discharge and precipitation data
Precipitation data
USGS Streamgage data
11
Analysis
Sep. 7, 2002
Sep. 2002 Loop 360 SH71 Barton Spring Barton Lost Shoal
Day Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs)
6 0.00 5.40 2.44 5.60 0.00
7 0.01 6.70 2.49 7.60 81.00
12
Analysis
Sep. 8, 2002
Sep. 2002 Loop 360 SH71 Barton Spring Barton Lost Shoal
Day Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs)
7 0.01 6.70 2.49 7.60 81.00
8 0.00 20.00 2.52 14.00 212.00
13
Analysis
Sep. 9, 2002
Sep. 2002 Loop 360 SH71 Barton Spring Barton Lost Shoal
Day Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs) Discharge (cfs)
8 0.00 20.00 2.52 14.00 212.00
9 0.00 32.00 2.53 33.00 9.10
14
Analysis
15
Conclusion
The land cover largely influences the discharge
rate and time to reach the peak point.
Soil layer
impermeable layer
runoff
runoff
16
Question
?