4th International Symposium on Flood Defence Toronto, Canada

May 6, 2008

1997 Red River of the North Flood 10 Years Later

PRESENTATION SUMMARYPRESENTATION SUMMARY• IntroductionIntroduction

– Overview (Overview (Mike RyanMike Ryan))• GeographyGeography

– Living with the Red (Living with the Red (M. ClamenM. Clamen))• Conclusions and RecommendationsConclusions and Recommendations

• Accomplishment'sAccomplishment's– Improvements in Flood Forecasting (Improvements in Flood Forecasting (D. LunaD. Luna))

• Mitigation Mitigation (Structural/non-structural/Policy/Legislation changes)(Structural/non-structural/Policy/Legislation changes)– North of the BorderNorth of the Border

• Manitoba (Manitoba (D. McNeilD. McNeil))– South of the BorderSouth of the Border

• US Federal (US Federal (J. DeHarnaisJ. DeHarnais))• US StateUS State (D. Frink) (D. Frink)

• Summary Summary – What’s next? (What’s next? (M. RyanM. Ryan))

• QuestionsQuestions

Introduction - OverviewIntroduction - Overview

WHERE IS THE RED RIVER OF THE NORTH?

FARGO/MOORHEAD

GRANDFORKS EAST GRAND FORKS

EMERSON

WINNIPEG

LAKE WINNIPEG

Introduction - Overview

Red River Basin Characteristics

Introduction - Overview

• Formed by glacial Lake Agassiz– Basin is characterized as glaciated plain with moraines, lakes,

wetlands, and lake plains

• Covers 45,000 mi2 (116,500 km2)– About 90% of area in US (40,000 mi2 or 103,600 km2)

• River meanders northward for 551 mi (887 km)– The river path is nearly double the straight-line distance

• Red River Floodplain– 60 mi wide (100 km)

at the widest point

Red River Basin Characteristics

Introduction - Overview

• Basin remarkably flat• Drops 229 ft (69 m) over

length• Average of 0.4 ft/mi

(0.08 m/km)

Daily flows– Maximum: 133,000 ft3/s (3,770 m3/s) April 26, 1997– Mean: 4,050 ft3/s (155 m3/s)– Minimum: 0.9 ft3/s (0.0255 m3/s) February 2, 1937

Red River Flow Characteristics

Introduction - Overview

FLOW DISTRIBUTION IN AN AVERAGE YEAR FOR

0%

10%

20%

30%

40%

50%

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

% O

F A

NN

UA

L F

LO

W

05OC001 - RED RIVER AT EMERSON RECORDED

Prepared by Manitoba Water Stewardship

Red River Flooding in 1997

Introduction - Overview

Annual Maximum Peak Streamflow for Red River of Annual Maximum Peak Streamflow for Red River of the North at Grand Forks, NDthe North at Grand Forks, ND

Introduction - Overview

Red River Flooding in 1997

Red River Flooding in 1997What caused the flooding?

• Substantial precipitation in fall of 1996• Early freezing of saturated ground in fall of 1996• Snowfall 300% or more of normal

Fargo…..117 in (297 cm) Grand Forks…..98 in (249 cm) Winnipeg…..90 in (228 cm)

• Melt of Snow pack and thawing of ice began in late March• Melt inhibited by late-spring blizzard on April 5-6, 1997

Wind-driven rain and sleet Severe drop in temperatures Winds to 70 mph (133 kph) Up to 2 ft (0.6 m) of snow Wind and ice toppled trees and power lines – no power for days

Introduction - Overview

Red River Flooding in 1997Economic damages

• Physical Damage/Costs– Estimates of 2 to 3 Billion Dollars

Introduction - Overview

Introduction - Overview

Red River Flooding in 1997 Farms and Agricultural Lands Flooded

• Inundated Land– US

• 7,040 mi2 (18,200 km2)– Canada

• 1,700 mi2 (4,400 km2)

– Almost of 20% of basin inundated at some point

Red River Flooding in 1997 Transportation – Disrupted

BRIDGES UNDERWATER STREETS AND ROADS FLOODED

ROADS WASHED OUT

Introduction - Overview

Introduction - Overview

Red River Flooding in 1997Grand Forks flooded

Psychological Damage/Costs

• There are damages resulting from major floods for which a monetary value cannot be determined

• Often the psychological damages following a major flood are the most difficult to overcome and may remain long after the clean up and replacement effort

Red River Flooding in 1997Moving Forward

• IJC recognizing that flooding will continue to impact the Red River basin

• IJC recognizing the social/economic costs associated with flooding will continue to increase

• Developed “Living with the Red”• 7 Conclusions• 28 Recommendations

Introduction - Overview