Future Flooding, EMAs Prepare
Jun 15, 2012

The worst floods in recorded history occurred in central China between July and November 1931, where as many as four million people died from drowning or related diseases such as cholera and typhus. Of the five deadliest floods on record, all have occurred in China. Most recently, in July 2012, torrential rains hit the central part of the country, causing in devastating floods and mudslides. At least 77 victims perished and millions were forced to evacuate their communities.

Simultaneously, heavy rains in southwestern Japan triggered landslides, cutting off thousands in mountainous districts and killing 26. “Some 250,000 people have been ordered to leave their homes in the prefectures of Fukuoka, Saga, Kumamoto and Oita,” said a BBC News report. Japan’s Self-Defence Forces responded quickly by flying in supplies and participating in search and rescue operations.
Seven thousand kilometres to the south, floods across eastern Australia forced more than 13,000 people to abandon their homes after record-high summer rains drenched three states, swelling rivers and causing dams to overflow. According to one news report, as flood waters raced by the town of Wagga Wagga in New South Wales, strangely, millions of spiders blanketed fields with “snow” – cobwebs – then clambered up trees and bushes.

In North America, the memory of massive flooding caused by Hurricane Katrina in late August 2005 lingers. Inadequately designed and built levees and flood walls in Greater New Orleans were overwhelmed by the storm surge; tens of billions of gallons of water flooded 80 percent of the port city and all of St. Bernard Parish in southeast Louisiana. More than 100,000 homes and businesses were flooded and 1,800 people were killed. Criticism from many quarters over the dismal response by municipal, state, and federal emergency management agencies to the Category-5 tropical cyclone and resulting flooding, eventually led to ­significant changes.

Flood Planning & Mitigation
Emergency Management Agencies (EMAs) prepare for floods in various ways, including ascertaining how much area will be inundated if certain water levels are reached. Flood maps showing vulnerable sectors are created and distributed to officials tasked with overseeing emergency planning and response.

Manitoba is one jurisdiction that takes the threat of floods and the need for preparation and mitigation very seriously. The Red River Flood of 1950 swamped in excess of 95,000 structures and 1,600 square kilometres (395,350 acres) of farmland. The disaster prompted the construction of the 47-kilometre-long Red River Floodway during the 1960s, which has saved an estimated $10 billion in damages in subsequent flood events, the worst to date occurring in 1997 (dubbed the “Flood of the Century”).

In February of each year, the Manitoba Flood Forecast Centre publishes its Spring Flood Outlook report online. The document includes maps of soil moisture readings taken around the province the previous autumn, and flood threat estimates for four major rivers (Red, Assiniboine, Pembina, and Souris) as well as the Interlake and other regions. Flood updates are issued as spring approaches and progresses.

Wendy Brogdon, executive assistant to director Kevin Davis of the Louisiana Governor’s Office of Homeland Security and Emergency ­Preparedness explained to FrontLine that each of the state’s 64 parishes, 15 local ­communities, 4 universities, 3 special districts and 1 Native American tribe “have a FEMA [Federal Emergency Management Agency]-approved, Disaster Mitigation Act-compliant hazard mitigation plan.”

Brogdon notes that “Louisiana has devoted extensive effort and resources to mitigate the effects of flooding. The state has committed in excess of $21 million in funding toward the development and updating of mitigation plans which allow the jurisdictions to be eligible for federal mitigation grants. Flooding has been identified as one of the top hazards in the State Hazard ­Mitigation Plan.”

Since Katrina, Louisiana’s government has improved its emergency planning, including “a comprehensive flood flight and search and rescue plan,” Brogdon indicated. “The planning effort included the Department of Transportation and Development, Office of Coastal Protection and Restoration, Department of Natural Resources, Louisiana State Police, Louisiana Sheriff’s Association, Louisiana Department of Wildlife and Fisheries, Department of Children and Family Services, Department of Health and Hospitals, National Weather Service-River Forecast Offices, and the United States Army Corps of Engineers (USACE).”

The planning effort included identifying potential threat areas using forecasting and modeling provided by USACE and the NOAA (National Oceanic and Atmospheric Administration). The state planning team worked with local governments to develop evacuee estimates, transportation requirements, and available shelter locations. “A second planning scenario was based on an immediate breach of the Mississippi River requiring the immediate evacuation and activation of water borne search and rescue missions,” said Brogdon.

Louisiana’s neighbour to the east, Mississippi, has not only experienced hurricane storm surges, but has the largest river system in North America running through it. Since the 1930s, USACE has created and maintained spillways and floodways to divert water surges into backwater channels and lakes, and route part of the Mississippi River’s flow to the Gulf of Mexico via the Atchafalaya Basin, circumventing Baton Rouge and New Orleans.

When asked by FrontLine about flood planning, Robert Latham, Mississippi’s EMA executive director, said: “All emergencies and disasters are local events. This is why we are pushing more communities to create plans at the local level which address their specific needs for evacuations and mass care, in order to take care of their own citizens. With well thought out local plans, the state will be better prepared to support these local governments during a disaster like a catastrophic flood.”

Flood emergency response
Flooding in parts of British Columbia in June of this year prompted B.C. officials to issue evacuation notices and standby warnings. “Emergency officials around B.C. and even Alberta are on alert as the mighty Fraser River, swollen by a melting snowpack and deluge of rain, threatens to breach dikes and damage homes, property and livestock near Vancouver,” reported the CBC News on 23 June. The day before, the B.C. Ministry of ­Justice announced that 1,000 provincial forestry firefighters along with Canadian Forces personnel from Edmonton, Esquimalt, and Vancouver were on standby to assist stricken communities. Two million sandbags were said to be available in case of major flooding across the province. ­Officials told reporters that the provincial emergency coordination centre and its three regional facilities in Prince George, Kamloops and Surrey, as well as 19 municipal operations centres, were involved in responding to the crisis. Hundreds of people were evacuated and, sadly, one man died.

Flooding in Manitoba in May 2011 prompted the provincial government to request help from Canada’s military; more than 100 soldiers were deployed. At the time, Paul Kentziger, planning officer with the Manitoba Emergency Measures Organization, told reporters: “We are so happy to get the military. This isn’t one of their prime functions but they’re a very concentrated force and they work hard.”

At the time, Lieutenant-Colonel William Fletcher, commander of the 1st battalion Princess Patricia’s Canadian Light Infantry Corps, stationed in Edmonton, commented that they were “filling sandbags about as fast as we can.” Reportedly, the soldiers’ filling rate was 2,500 sandbags per hour. “In terms of our approach, it’s not unlike any military operation,” Fletcher remarked. “It’s all about sourcing the information, coming up with a plan and then trying to execute it. The one thing we can always rely on is the hard work of our soldiers.”

More water, more floods
It appears that global flooding incidents will only increase in the coming years. A ScienceDaily.com report on 24 June 2012 commented that “Sea levels around the world can be expected to rise by several metres in coming centuries if global warming carries on. Even if global warming is limited to 2° Celsius, global-mean sea level could continue to rise, reaching between 1.5 and 4 metres above present-day levels by the year 2300, with the best estimate being at 2.7 metres, according to a study just published in [the scientific journal] Nature Climate Change.”

Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, co-author of the study, said the risks are significant. “As an example, for New York City it has been shown that one metre of sea level rise could raise the frequency of severe flooding from once per century to once every three years,” he told Science Daily. “Also, low lying deltaic countries like Bangladesh and many small island states are likely to be severely affected.”

Few nations are immune to such disasters. This summer, an online Canadian Underwriter report included the following information: “Global warming could almost double the number of properties at significant risk of flooding in the United Kingdom by 2035 unless loss reduction plans are put in place, argues a committee appointed by the U.K. government to study climate change.” In the fall of 2000 alone, parts of England and Wales experienced the heaviest rains in 230 years and flooding caused $1.7 billion in insured damages.

This year, April to June was the wettest quarter on record in Britain, and further heavy rain in July resulted in extensive flooding. Surprisingly, however, The Guardian reported in July that “300 flood defence schemes have been left unbuilt because of government cuts.”

Warnings from scientists about anthropogenic (human-caused) global warming resulting from burning fossil fuels and pumping heat-trapping greenhouse gases (GHGs) into the atmosphere have largely gone unheeded (until recently). Climate change due to global warming has been one of the predicted results. A February 2011 Nature Science article, entitled Increased flood risk linked to global warming, noted that “Rises in global average temperature are remote from most people’s experience, but two studies in this week’s Nature conclude that climate warming is already causing extreme weather events that affect the lives of millions.” Since GHGs and temperatures worldwide are forecast to rise, EMA ­officials and response personnel in many countries will likely be dealing with more flooding in the future.

Blair Watson is a FrontLine correspondent based in British Columbia.
© FrontLine Security 2012