Introduction. Definitions. Methods

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Infrastructure Disruptions and Interdependencies during Flood Events

By: Andrew Yu March 30th_{, 2010}

Introduction

During disaster events many infrastructure systems are vulnerable to damage and service disruption. Major infrastructure sectors are highly interdependent upon one another, such that damage in one sector may lead to disruptions in others. The objective of the Analyzing Infrastructures for Disaster-Resilient Communities (AIDRC) research project is to promote a better understanding of infrastructure vulnerabilities and

interdependencies in order to advance the processes of mitigation and create more disaster-resilient urban regions.

On November 17, 2009, members of the AIDRC research group conducted a workshop with expert participants who possess professional experience managing or working within major infrastructure sectors in the Metro Vancouver area. Using a hypothetical flood scenario, the workshop aimed to elicit insight regarding expected service disruptions to infrastructure systems in the Metro Vancouver area in the event of a major flood. In preparation for the workshop, a database was created to document significant infrastructure disruptions and interdependencies during past major flood events in other parts of North America. Using four flood examples, this report summarizes the findings of the Flood Events database.

Definitions

The Government of Canada defines critical infrastructure systems as “physical and information technology facilities, networks, services and assets, which if disrupted or destroyed would have a serious impact on the health, safety, security or economic well-being of Canadians or the effective functioning of governments in Canada.”1_{The AIDRC project focuses on many of these sectors, including electricity, water, healthcare and} transportation.

Infrastructure Failure Interdependencies (IFIs) may be defined as “failures in interdependent infrastructure

systems that can be traced back to some initial infrastructure failure associated with an extreme event.”2 For additional definitions, see the KOA project glossary.

Methods

The Flood Events database was developed with information from a variety of sources, including newspaper articles, government reports and academic journals. Nine flood events that have occurred in Canada and the

1 Public Safety and Emergency Preparedness Canada. 2004. Government of Canada Position Paper on a National Strategy for Critical Infrastructure Protection, p. 5.

2 S.E. Chang, T.L. McDaniels, J. Mikawoz, and K. Peterson. 2006. “Infrastructure failure interactions in extreme events: the 1998 Ice Storm,” Natural Hazards, Vol. 41, No. 2, pp. 337-358 at 338).

Acknowledgements: Dr. Tim McDaniels, Dr. Stephanie Chang, and Courtenay Beaubien

This study was supported by Infrastructure Canada through the Knowledge, Outreach, and Awareness Program.

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United States between 1993 and 2009 were documented. Information from four of these flood events was presented as background information during the workshop. One of the objectives of presenting this

information was to draw similarities between various flood events with regards to the types of infrastructure disruptions and interdependencies which occurred. The service disruption scale (Figure 1), developed

previously by researchers in the AIDRC project, and information from the database were used to generate service disruption charts for each event. These charts were used to display the degree of disruption (ranging from no loss to severe disruption) experienced by various infrastructure sectors. These service disruption charts were similar to the ones used during the AIDRC project's previous workshop, which utilized an earthquake scenario.3

Results

Four events were presented during the workshop to highlight the types of infrastructure disruptions and interdependencies that may occur during a flood event:

• 1993 Great Midwest Flood • 1997 Red River Flood • 2005 Calgary Flood • 2008 Iowa Flood

Each example included a service disruption chart, which shows the degree of disruption experienced by each major infrastructure sector during the duration of the event, ranging from 0 hours to 2 weeks.

3 Analyzing Infrastructures for Disaster-Resilient Communities. Practitioner Report #2 - Characterizing Infrastructure Vulnerabilities: Lower Mainland Earthquake Scenario Example. URL: http://www.chs.ubc.ca/dprc_koa/

Figure 1: Service Disruption Scale

* Infrastructure disruptions of high impact and high extent are identified as severe disruptions

* Disruptions of high impact/low extent or high extent/low impact are identified as moderate disruptions *Disruptions of low extent/low impact are identified as slight disruptions

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1993 Midwest Flood:

The 1993 Midwest Flood was caused by the flooding of the Upper Mississippi and Missouri Rivers and was one of the most damaging natural disasters in U.S history, spanning a total of nine states in the Midwest region. Flooding occurred in Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota and Wisconsin. During the flood, power outages occurred in numerous parts of the Midwest, which consequently led to disruptions in other infrastructure sectors.4_{Water treatment was especially vulnerable because of} flooding and power outages. In Des Moines, Iowa, drinking water was unavailable for a month, affecting over 250,000 people.5_{Transportation was also affected throughout as numerous stretches of roads, bridges and} highways were closed due to flooding and structural damage. As a result of power outages, train stations and commercial airports experienced service disruptions and traffic lights stopped functioning. In Grafton, Illinois, the Illinois Department of Transportation constructed a road leading from the city in order to keep it from becoming isolated during the flood.6_{The healthcare sector was also severely affected during the flood as} hospitals and other medical facilities were forced to close down or evacuate patients due to power and water shortages. Healthcare was also disrupted by transportation barriers, as ambulances could no longer travel through flooded roads, and important food and medical supplies could no longer be delivered to hospitals.7 Figure 2 displays the 1993 Midwest Flood service disruption chart.

4 NY Times, “The Midwest Flooding; Flood leaves 250,000 without water to drink,” July 12, 1993

5 Leads from the Morbidity and Mortality Weekly Report, “Public Health consequences of a Flood Disaster – Iowa, 1993.” Journal of the American Medical Association, Sept.1993, vol.270, no.12

6 FEMA, “The 1993 Great Midwest Flood: Voices 10 Years Later.” 2003

7 Axelrod, Corrine; Killam, Phillip; Gaston, Marilyn; Stinson, Nathaniel, “Primary Health Care and the Midwest Flood Disaster,” Public Health Reports, September-October 1994, vol 109, no. 5, 601-605

Figure 2: Service Disruption Chart – 1993 Midwest Flood

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1997 Red River Flood:

The Upper Red River which includes the region around North Dakota and Manitoba is well-known as a flood-prone area. It has experienced numerous floods in the past, including major ones in 1897 and 1950. The Red River Flood of 1997 was especially severe, affecting both Canada and the United States. In North Dakota, over 30,000 households experienced power outages due to damaged transmission lines.8_{Communications}

infrastructure such as television and radio towers was also damaged. Water and wastewater treatment capabilities were compromised in numerous urban areas in North Dakota, Minnesota and Manitoba. In Ste. Agathe, Manitoba, water treatment was disabled for a month.9_{Numerous hospitals, nursing homes and other} medical facilities were evacuated in Fargo and Grand Forks. In all affected areas, transportation routes such as roads, bridges and highways were closed. Disruption to emergency services became a major issue after fire crews failed to reach a fire in downtown Grand Forks and 11 buildings across four city blocks were damaged.10 In many cases, emergency services were unable to travel through flooded roads or gain access to damaged or submerged fire hydrants. Figure 3 displays the service disruption chart for the event.

8 FEMA, “Grand Forks 1997 Flood Recovery Disaster Information.” 1997

9 Interim Report of the International Red River Basin Task Force to the International Joint Commission, “Red River Flooding Short-Term Measures” December 1997

10 FEMA, “Grand Forks 1997 Flood Recovery Disaster Information.” 1997

Figure 3: Service Disruption Chart – 1997 Red River Flood

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2005 Calgary Flood:

Unlike the 1993 Midwest and 1997 Red River floods, the 2005 Calgary Flood affected a much smaller

geographic area. The event resulted from the flooding of the Bow River, Elbow River and Fish Creek during the summer of 2005, and impacted many parts of the Calgary Metropolitan Area. Most of the affected

infrastructure systems experienced only minor disruptions as a result of this event. The Discovery Ridge area was affected by minor power outages, and the municipal government activated “level 4” water conservation restrictions during the flood, which urged voluntary conservation of drinking water and banned all outdoor water activities.11_{Sewage backups occurred in several flooded areas, and a total of 25 city roads were closed} during the flooding. Holy Cross Hospital in Calgary was nearly flooded, but did not ultimately evacuate

patients. In total, the City of Calgary estimated $13.8 million in infrastructure damages.12_{Figure 4 displays the} service disruption chart for the event.

2008 Iowa Flood:

The 2008 Iowa Flood resulted in the flooding of several Upper Mississippi tributaries and affected most of Iowa, as well as parts of Indiana. Heavy flood damage occurred in the city of Cedar Rapids, where 30,000 residents experienced power outages due to damaged generating stations.13_{Water and wastewater treatment} in the city was also threatened due to power outages and the direct flooding of treatment facilities. Other urban areas, including Columbus Junction, also experienced water shortages. Due to the lack of access to drinking water, the National Guard was activated to distribute bottled water to citizens.14_{Transportation} across the state of Iowa was affected, with the closure of numerous roads, railway tracks and sections of 6 interstate highways. Barge traffic was also stopped throughout the affected area. In the healthcare sector, several hospitals, including Mercy Medical Centre in Cedar Rapids, were evacuated during the flood. A high mosquito population became a major public health concern due to fears of a West Nile Virus outbreak. Figure 5 displays the service disruption chart for the event.

11 City of Calgary, “2005 Flood Report: The City of Calgary's Report on the 2005 June Flooding in the Elbow and Bow River Watersheds.” 2005

12 Ibid., City of Calgary, 2005.

13 Electric Utility Week, “Corps closes part of Mississippi River to barges; power plants shut from Cedar River flooding,” June 16, 2008

14 The Washington Post, “Already Flooded Iowa Town Avoids Catastrophe,” June 16, 2008

Figure 4: Service

Disruption Chart – 2005 Calgary Flood

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Summary / Key Findings

Data on infrastructure disruptions and interdependencies from the four flood examples revealed similarities between the events with regard to the types of infrastructure systems affected during floods. The data suggests that major sectors, such as power, water, wastewater, healthcare and transportation are often

vulnerable during major floods. In addition, many of these systems are interdependent, and a disruption in one sector (e.g., power) may result in disruptions in other sectors (e.g., water, healthcare).