1 Floods - Lecture 1 Schultz House, Johnstown, Pennsylvania 1889 McCullough, David, 1968, The Johnstown Flood: New York, Simon & Schuster, Inc., 302 p What Causes Flooding? • What Causes High Water? • What Causes Damage When There is High Water? Human Role Floodplain Encroachment People & Structures in Harm’s Way Worsens Floods Downstream Dams Dam Failures Levees Worsens Floods Downstream Levee Failure Increases Flow Energy Land-Use Changes Changes in Runoff Coefficients
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Johnstown, Pennsylvania Schultz House, Floods - Lecture 1pages.geo.wvu.edu/~kite/2006FallGEO493FLect9_10Floods.pdf · Ignorance of Rivers and Streams Poor (Selective?) Memory of Historic
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1
Floods -Lecture 1
Schultz House,Johnstown, Pennsylvania
1889
McCullough, David, 1968, The Johnstown Flood: New York, Simon & Schuster, Inc., 302 p
What Causes Flooding?
• What Causes High Water?
• What Causes Damage WhenThere is High Water?
Human RoleFloodplain Encroachment
People & Structures in Harm’s WayWorsens Floods Downstream
Dams Dam Failures
LeveesWorsens Floods DownstreamLevee Failure Increases Flow Energy
Land-Use ChangesChanges in Runoff Coefficients
2
Flood Problems are People Problems
Ignorance of Rivers and Streams
Poor (Selective?) Memory of Historic Floods
Arrogance of Our Ability to Overcome Nature
Greed to Exploit Floodplain Property
Lack of Zoning and Planning
Sooner or later, the river exerts authority over its entire domain!
Sooner or later, the river exerts authority over its entire domain!
– Average Time Between Events of a Given Size or larger
Hydrograph
Discharge
“Base Flow”New
“Base Flow”
Crest
Ris
ing
Lim
b
Falling Limb
0 cfs
3
Real-Time Flow Links for Flood Chasers & River Rats (beware some links have "decayed")
http://www.geo.wvu.edu/~kite/welcome.htm
Hid slide in 2006 because too many lin
ks were dead
http://www.erh.noaa.gov/er/pit/hydro.htm
NWSFO PITTSBURGH PA HYDROLOGIC SERVICES AREA Hydrology/River Products Web Page
US Geological Survey Real-Time Stream Flow Info
• http://water.usgs.gov/cgi-bin/daily_flow?wv
– USGS 03206000 OHIO RIVER AT HUNTINGTON, WV– USGS 01605500 SOUTH BRANCH POTOMAC AT FRANKLIN, WV– USGS 03200500 COAL RIVER AT TORNADO, WV– USGS 03202400 GUYANDOTTE RIVER NEAR BAILEYSVILLE, WV– USGS 03204000 GUYANDOTTE RIVER AT BRANCHLAND, WV
4
Deckers Creek StagePeak: Early a.m. 23rd
Not
e V
ertic
al A
xis
Cha
nge
Guyandotte River Hydrograph July 2001
5
Approaches to Flood “Prediction”National Weather Service
• Flood Watch, Flood Warning• Based on
Flow in SteamsAntecedent Conditions: Ground
Saturation, etc. Current Conditions: Precipitable
Moisture Weather Forecast
IFLOWS: West Virginia Automated Flood Warning System (AFWS)
Plants do not reduce flooding when it is very dry or very wet!
Fig. 3.23
Seasonal Soil Water Balance in Ohio
17
U.S. Annual Precipitationhttp://streams.osu.edu/book/PowerPoints/chapter2.ppt#263,9,Slide 9
Annual Pan Evaporation in the USA
Flood Climatology
Next Five Figures are from
Some Perspectives on Climate and Floods in the Southwestern U.S.U.S. Geological Surveywhich is abstracted primarily from:
Hirschboeck, K.K., 1991, Climate and floods, in Paulson, R.W., Chase, E.B., Roberts, R.S., and Moody, D.W., Compilers, National Water Summary 1988-89--Hydrologic Events and Floods and Droughts: U.S. Geological Survey Water-Supply Paper 2375, p. 99-104.
WEEKLY SUMMARY OF PEAK FLOWS IN THE OHIO RIVER BASIN
0
20
40
60
80
100
120
140
160
Jan 1-
7
Jan 22
-28
Feb 12
-18
Mar
5-11
Mar
26-A
pr 1
Apr 16-2
2
May
7-13
May
28-Ju
n 3
Jun 18
-24
Jul 9
-15
Jul 3
0-Aug 5
Aug 20-2
6
Sep 10
-16
Oct 1-7
Oct 22
-28
Nov 12
-18
Dec 3-
9
Dec 24
-31Jan Dec
Freq
uenc
y
0
40
80
120
160
Mar May Jul OctJunFeb Apr Aug Sep Nov
Qmax Week by Week: All Events
21
Weekly Qmax Summary
* March, Week 2: 8% of Qmax Events* March 1- April 10: ~28% of Qmax Events* Late January “Thaw”: Above Normal * Late Spring to Mid-Summer: Above Normal * October, Week 4: None of 1832 Qmax Events* Individual Events Matter
Month of Qmax <1.0 km2 Basins
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Freq
uenc
y
20
0
Month of Qmax 10-100 km2 Basins
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Freq
uenc
y
70
0
22
Month of Qmax 1000-10,000 km2 Basins
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Freq
uenc
y
140
0
Month of Qmax >100,000 km2 Basins
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Freq
uenc
y
10
0
Jan 1937Total Precip.
as % of “Normal”
23
Jan 1937: Portsmouth, Ohio
Jan 1937: 60 ft Floodwall Topped, Portsmouth, Ohio
There are floods and there are floods!
• Variability Contolled by – Basin Size – Topography & Other Basin Characteristics
The Buffalo Creek Flood: an Act of Mancall nos. VHS video: WVU-AVL VT3610, DVD: MEDIA DV1359 AV LIB
• Where (and what) is Logan County?• What is an “Act of God”?
– Precipitation Amounts in Feb 1972?• Who was responsible? Who provided Relief?• What were the dams built from?
– Slate?• Why were the “dams” built?• What was Pittston Coal’s response to the flood?• What was the State government response to the flood?
– Gov. Moore’s “lame duck” resolution w/ company• What was the citizens response?
– $100,000,000 Class Action Suit, settled for >$13,000,000 • What were conditions 2 years later?• “Buffalo Creek Revisited”(1985)• What are general lessons to be learned?
Other
• Ground-breaking Class Action Suit• Lessons for “FEMA”