iowa flooding
DESCRIPTION
Iowa Flooding. Mark Hughes November 25, 2008. University of Iowa News Service. Background. Two “500 year” events Major damage to the University of Iowa and surrounding area. University of Iowa News Service. Where In Iowa?. Iowa State University GIS Facility. Flood Elevations. - PowerPoint PPT PresentationTRANSCRIPT
Iowa FloodingMark Hughes
November 25, 2008
University of Iowa News Service
Background
• Two “500 year” events• Major damage to the University of Iowa and
surrounding area
University of Iowa News Service
Where In Iowa?
Iowa State University GIS Facility
Flood Elevations
• Iowa River USGS Gauging Station at Iowa City, IA
– 1993 Maximum Elevation = 645.17 ft NGVD 29– 2008 Maximum Elevation = 648.29 ft NGVD 29
11/14
1/3
2/22
4/12
6/1
7/21
9/9
615
620
625
630
635
640
645
650
655
Water Surface Elevations at Iowa City
2008 Elevation 1993 Elevation
Wat
er S
urfa
ce E
leva
tion
(ft)
Calculated Flooding Map
• Map Area Flooded in 1993 and 2008
How accurate is this map?
• Trying to get actual flood data map from the University of Iowa
• Dam before gauging station
Compare To Flood Maps
Map Based on Water Elevation at Iowa City
Actual Iowa City Flood Map
The National Center for Airborne Laser Mapping
NCALM Mapped
2008 Precipitation and Pool Elevation
3/1
3/21
4/10
4/30
5/20
6/9
6/29
7/19
0
10
20
30
40
50
60
70
80
90
660
670
680
690
700
710
720Precipitation and Pool Elevation in 2008
Precipitation Pool Elevation
Prec
ipita
tion
(mm
/hr)
Pool
Ele
vatio
n (ft
)
Spill Way Height
Pool Elevation and Discharge
1/3
2/22
4/12
6/1
7/21
9/9
10/29
660
670
680
690
700
710
720
0
2000
4000
6000
8000
10000
12000
Pool Elevation and Discharge
Pool Elevation Discharge
Pool
Ele
vatio
n (ft
)
Disc
harg
e (c
fs)
To Do
• Get real flood data• Calculate volumes of storage and discharge• Further look into dam operation requirements
Questions ??