hydraulic and hydrologic considerations in planning flood risk management class exercise chuck...
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Hydraulic and Hydrologic Considerations
in Planning
FLOOD RISK MANAGEMENT
CLASS EXERCISE
Chuck Shadie
Mississippi Valley Division
Objective
• The students will complete an exercise designed to improve their abilities in selecting the types of alternatives to analyze during a flood damage reduction study.
Exercise Impacts of Various Flood
Risk Management Measures
• Have the students predict the flood reduction impacts of various types of measures.
• Explore the consequences of such measures on upstream and downstream areas of the watershed.
Denham SpringsDenham Springs
Lake Lake MaurepasMaurepas
New OrleansNew Orleans
MISSISSIPPIMISSISSIPPI
LOUISIANALOUISIANA
Lake Lake PontchartrainPontchartrain
Baton RougeBaton Rouge
E. Baton R.
Comite RiverComite River
St.
Hel
ena
Livingston
E. Feliciana
Ascension
St.
Jo
hn
St. James
Iberville
AmiteWilkerson
Franklin Lin
coln
Amite RiverAmite River
Amite River and Tributaries Study Map
The Amite River BasinThe Amite River Basin
- 2,200 square miles- 2,200 square miles
- Includes portions of East Baton Rouge,- Includes portions of East Baton Rouge, Ascension, Livingston, East Feliciana, Ascension, Livingston, East Feliciana, St. St. Helena, Iberville, St. James, St. John, Iberville, St. James, St. John as well as 4 counties in Mississippi as well as 4 counties in Mississippi
- 20% of the basin lies in Mississippi- 20% of the basin lies in Mississippi
- 62% of the basin lies above Denham - 62% of the basin lies above Denham Springs Springs
- Only 7% of the basin is urbanized- Only 7% of the basin is urbanized
1983 Flood1983 Flood Amite River Basin Amite River Basin
• The 1983 flood event was the flood ofThe 1983 flood event was the flood of record for most of the Amite River Basin. record for most of the Amite River Basin.
• It flooded over 357,000 acres and causedIt flooded over 357,000 acres and caused over $172 million in damages.over $172 million in damages.
• Significant flooding also occurred in ’73, Significant flooding also occurred in ’73, ’ ’77, ’79, ‘89, ‘90, and ’93.77, ’79, ‘89, ‘90, and ’93.
1983 Land Use Conditions in 1983 Land Use Conditions in Amite River Basin Amite River Basin
• Baton Rouge & Denham Springs area – Baton Rouge & Denham Springs area – urbanized – heavy flooding damages along urbanized – heavy flooding damages along tributariestributaries
• Amite RiverAmite River– North of Denham Springs – heavily forested North of Denham Springs – heavily forested
and agricultural areas floodedand agricultural areas flooded– South of Denham Springs – wide, wetland South of Denham Springs – wide, wetland
floodplains with small communities floodedfloodplains with small communities flooded• Comite River upstream of Baton Rouge – Comite River upstream of Baton Rouge –
heavily forested/agricultural use with small heavily forested/agricultural use with small communities developingcommunities developing
Legend
Headwater
Backwater
Denham Springs
Scotlandville
BatonBatonRougeRouge
Baker
Zachary
PortVincent
Co
mite R
iverC
om
ite River
Mississip
pi
Mississip
pi
Amite River
Amite River
Beaver B
ayou
Beaver B
ayou
#1#1
Amite
Jones CreekJones Creek
Bayou Fountain
Bayou Fountain
Bayou Bayou ManchacManchac
Dawson Creek
Dawson Creek
JonesJones
Tri
b.
Tri
b.
Liv
ely
B.
Liv
ely
B.
#2#2#1#1 #2#2
Weiner BWeiner B
Trib.Trib.
Clay Cut BayouClay Cut Bayou
North
BR.
North
BR.
War
dW
ard
Ward Creek
Ward Creek
Bla
ckw
ater
Bay
ou
Bla
ckw
ater
Bay
ou
RiverRiver
Causes and Types of FloodingCauses and Types of Flooding- There is no one solution in a 2,200 sq mi basin- There is no one solution in a 2,200 sq mi basin
- Three types of flooding must be addressed:- Three types of flooding must be addressed:
• Basin-wide floodingBasin-wide flooding associated with Amite associated with Amite River (headwater and backwater) River (headwater and backwater)• Headwater floodingHeadwater flooding (not assoc with Amite River) (not assoc with Amite River)• Backwater floodingBackwater flooding (not assoc with Amite River) (not assoc with Amite River)
- - Basin-wide floodingBasin-wide flooding occurs when a heavy rainfall occurs when a heavy rainfall occurs throughout the basinoccurs throughout the basin
- - Headwater floodingHeadwater flooding occurs in the upper reaches of occurs in the upper reaches of streams, usually caused by localized rainfall eventsstreams, usually caused by localized rainfall events
- - Backwater floodingBackwater flooding is caused when water backs up is caused when water backs up from the main waterwayfrom the main waterway
ExerciseExercise-As a team, using material from lectures and As a team, using material from lectures and notebook, and the watershed information provided:notebook, and the watershed information provided:
-Brainstorm potential flood damage reduction Brainstorm potential flood damage reduction measures that could be analyzed for the Amite measures that could be analyzed for the Amite River Watershed.River Watershed.
-Try to develop 2 or more alternative proposals for Try to develop 2 or more alternative proposals for the Amite River, the Comite River, and the the Amite River, the Comite River, and the tributariestributaries
-How will each potential alternative impact flooding How will each potential alternative impact flooding in the watershed?in the watershed?
-What additional issues (environmental, What additional issues (environmental, engineering, economics, etc) need to be engineering, economics, etc) need to be considered?considered?
Exercise Summary
• Each Team Present Their Conclusions from the Exercise