Canadian Underwriter
Feature

Weather Beaten?


March 1, 2014   by Greg Meckbach, Associate Editor


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Canadian municipal risk managers face the challenge of dealing with the fallout from a variety of natural hazards, ranging from floods to landslides and wildfires. And experts warn that the double whammy of climate change and a projected rise in sea level is only going to make these hazards more frequent and severe.

Academics studying urban planning contend that local officials can address these challenges by restricting development, while some governments are either contemplating or carrying out billions of dollars worth of major capital projects, such as enlarging sewers, constructing and improving dikes and installing dry ponds to collect excess rainwater. Some risk managers who work for municipalities report their employers are looking to Ottawa for cash, in the wake of the promise from the federal government, in February, of $200 million in disaster mitigation funding.

“We have seen too much of this surface flooding,” says Roman Parzei, director of revenue and risk management for the City of Brampton, northwest of Toronto. “So going forward in terms of our infrastructure – especially when we have to either replace it or emplace it in our new subdivisions – we have to realize that maybe the size of the sewers we are putting in need to be enlarged,” Parzei says.

In Brampton, it is the urban landscape, not the rivers, that are the problem.

“The rivers are less of a threat than the urban flooding, which is the storm sewers not being able to handle the extreme rains we’ve been having over the last few years,” Parzei notes. “Most of the banks of our rivers have been transformed into parkland, so even if we do have flooding, the rivers are going to overflow into parkland. There are really very few structures that are affected by that,” he reports.

Sometimes, however, there is simply too much rainfall for areas not to be affected. Consider July 8, 2013, when the Toronto area received more rain in a single day than the normal amount for the entire month. The deluge, and subsequent flooding, resulted in Canada’s third most expensive disaster, when measured by insured losses. That day, more than 126 millimetres of rain fell at Toronto-Pearson International Airport, which is about 10 kilometres southeast of downtown Brampton.

“It was basically over the roads,” Parzei says of the rain July 8. Brampton’s storm sewers were built for above-average rainfall “but they are not built for the kind of extreme rains that have been happening lately, and with all the pavement that we put everywhere – driveways and roads and parking lots – the water has nowhere else to go,” he points out.

NATIONAL DISASTER MITIGATION PROGRAM

“In the end, you are basically going back to the same well – the taxpayer,” says Alain Normand, manager of Brampton’s emergency management office. Asked whether the City of Brampton plans to seek funding from upper levels of government, Normand replies, “That’s the $100 million question.”

The City of Edmonton is also weighing whether or not to ask the federal government for some help on the flooding challenge. “There were a couple of funding strategies released in the latest federal budget that the city is going to avail itself of once the details come out,” says Don Marshall, director of risk management for the city, alluding to the proposed National Disaster Mitigation Program (NDMP).

That program was announced February 13 when the ruling Conservatives released the federal budget for the 2014-2015 fiscal year. Under the NDMP, the federal government is promising to provide $200 million over five years, starting in the 2015-2016 fiscal year.

“This program will support investments in structural mitigation measures, such as infrastructure to control floods that can reduce the impact of severe natural disasters,” Ottawa promises in the budget document. “The costs of projects will be shared with provinces and territories.”

In 2006, the City of Edmonton had identified 43 zones at risk of flooding, and approved $146 million for flood prevention measures. “They are building things like dry ponds, for example, so if there is excess surface water – if you get these severe events – the water goes into them,” Marshall reports. “The water is released gradually after the event, so you don’t get the flooding.”

Marshall suggests the city witnessed “quite a few sewer back-ups” in the summer of 2013. As a result, city officials are “doing a more comprehensive review right now just to see what else they need to do” to deal with the problem, he adds. “Some of this work is going to cost a lot of money as well.”

The North Saskatchewan River – which runs through Edmonton – crests in the spring after severe weather events, and overland flooding is “fairly significant” in some of the city’s neighbourhoods, Marshall points out, but adds that the greatest concern in the city is severe weather.

“Basically, the sewers were designed years ago and we have found that, with climate change, we get a lot more severe events,” he reports. “They are in localized areas, and quite often the sewers cannot handle the sudden influx and then you get a lot of sewer back-ups.”

All that water can bring about an additional challenge for city officials: an increase in subrogated claims from property insurers.

“Three or four years ago, it was fairly unusual for an insurer to put us on notice, but that has become almost routine now,” Marshall says. “After almost every sewer back-up event, we typically get three or four insurers that put us on notice for their subrogated interests.”

RAINFALL UPS VULNERABILITY

Marshall believes climate change “has made a difference” in the vulnerability of Edmonton to natural hazards.

“Certainly the forecasting we are seeing for the Edmonton area over the next 50 years – it is going to get progressively worse,” he says. “They are prognosticating that the average mean temperature will continue to rise and I am anticipating that will create more problems as we progress.”

Similar predications are being made for the Toronto area. The paper, Toronto’s Future Weather and Climate Driver Study: Outcomes Report, projects climate patterns for the Toronto area in 2040-2049. Prepared by SENES Consultants Ltd. and commissioned by the City of Toronto’s environment office, the report was submitted to city council before the July 8, 2013 rainstorm. SENES included a chart comparing actual weather in 2000-2009 to the weather patterns projected from 2040 through 2049. For example, the maximum amount of rain in one day, in 2000-2009, was 66 millimetres, but that amount is projected to increase to 166 millimetres by 2040-2049. The average temperature is predicted to increase by 4.4 degrees Celsius by 2040-2049 in Toronto, while the maximum hourly wind speed is predicted to drop from 92 kilometres/hour to 48 km/h.

Despite the drop, wind is still an issue on the radar of municipal risk managers. “We are at the tail end of the Ontario tornado alley,” Parzei says from Brampton. An F4 tornado hit Barrie, north of Toronto, on May 31, 1985, killing 12, while a less severe tornado hit Vaughan, also north of Toronto, on August 20, 2009. That day, Environment Canada reported at least 18 tornadoes in Ontario.

“That was just right next door to us,” Parzei says of the Vaughan tornado. “Five minutes earlier and it would have been in Brampton.”

And storms are becoming more severe, he says. “The question becomes, are we prepared to handle this stuff on a more frequent basis?”

BILLION-DOLLAR PROBLEM

In Toronto, city officials are preparing to address the risk of more frequent and severe weather. Ongoing efforts include the Basement Flooding Protection Program, which is meant to improve the sewer system and overland drainage routes. The program includes a subsidy for homeowners “to install flood protection devices, including a backwater valve, a sump pump and pipe severance and capping of the home’s storm sewer or external weeping tile connection.”

In its 10-year capital budget and plan submitted to city council last December, Toronto Water recommended that the city approve a total of $962 million in funding towards the program over 10 years.

“Retrofitting an area to accommodate the higher level of storm drainage and overland flow controls in existing, fully developed areas present the most significant challenge in terms of cost, scheduling and disruption to the local communities,” Toronto Water notes in its analysis of its capital spending plan. “To date, $91.0 million has been spent to upgrade over 1,300 kilometres of storm and sanitary sewers, build two surface storage ponds, and build one underground storm storage tank to meet the enhanced level of service requirements required under the Basement Flooding Protection Program,” the analysis notes.

Adds Toronto Water, “Storm drainage improvements are being made to provide protection from a 1-in-100-year return frequency storm event, up from the current 1-in-2 to 1-in-5-year return frequency storm… where feasible, as part of the City’s Climate Change Adaptation Strategy.”

$10-BILLION BILL

The “general opinion,” from “everyone who studies natural hazards and climate change,” is that natural hazards will become more frequent and more severe, says Mark Stevens, an assistant professor at the University of British Columbia’s school of community and regional planning. Stevens, a former municipal planner from Oregon, currently studies government land-use planning, growth management and natural hazard mitigation.

Stevens cautions that one projected consequence of climate change will be a rise in sea levels, and one Canadian urban area facing this threat is Vancouver.

The cost of protecting Vancouver and its suburbs is estimated in the billions. In 2012, British Columbia’s Ministry of Forests, Lands and Natural Resource Operations published a report in which it estimated the cost of providing flood protection in the Fraser Delta, if the sea level were to rise one metre by 2100, as predicted. Although the estimate is slightly shy of $10 billion, Cost of Adaptation: Sea Dikes & Alternative Strategies only covered the area between the Pacific Ocean and the Port Mann Bridge, where the Trans-Canada Highway crosses the Fraser River, about 35 kilometres east of downtown Vancouver. As such, the estimate does not account for protecting parts of the City of Surrey upstream from the Port Mann Bridge, or municipalities farther east.

The area downstream and west of the Port Mann Bridge encompasses 250 kilometres of shoreline and dikes, and the total estimated cost of flood protection is $9.47 billion, the report states. Of that amount, $880 million would be required for structural flood protection, $1.58 billion for property acquisition and $3.25 billion to “achieve seismic resilience,” it adds.

“The conclusions and costs are still valid,” Neil Peters, British Columbia’s provincial inspector of dikes, says of the report. “There certainly have been a number of new studies and initiatives that have started since then, but we do not have the conclusions and findings from those yet.”

In an interview, Peters reports that the province is “now doing a study on how sea level rise would affect the Fraser River flood levels upstream of Port Mann Bridge.”

Dikes “have a long history of use within the Fraser Valley and are the most common form of structural flood protection,” notes The Cost of Adaptation: Sea Dikes & Alternative Strategies. Both the upgrading of existing dikes and construction of new dikes “are potential options to protect against sea level rise,” the report adds. Other options cited by the study include retreating from or avoiding certain areas.

“For coastal communities, sea level rise is a permanent change and at this point, it’s the planning implications that are the most difficult,” Peters suggests. “It’s not that immediately we are going to have more serious floods, but it’s the long-term planning implications that are critical, in terms of future development and how it is set out so that it can be protected, so it can be sustainable. To me that is the issue with sea level rise.”

The study estimates “deep soil mixing” – meant to protect dikes in the event of an earthquake – could cost $2.2 billion. An earthquake, Peters suggests, could cause a river bank to collapse.

“The seismic design involves improving the ground under the location where the dike is,” he explains. “This cost actually relates to just a few of the dikes where they are located right along the river bank.”

But Peters warns that with climate change, “it is fairly clear from the science that there will be more flood potential” from streams draining from the mountains into the Fraser River. “It is not clear at all, at this point, what the impact of climate change could be on actual peak floods in the Fraser River itself, because it’s such a large stream and it drains such a complicated geography,” he adds.

That said, climate change will make communities north of downtown Vancouver more susceptible to natural hazards, suggests Dorit Mason, director of the North Shore Emergency Management Office (NSEMO), an inter-municipal agency of the City of North Vancouver, the District of North Vancouver and the District of West Vancouver. NSEMO has identified several natural hazards within the three municipalities it serves.

“Although we think about earthquake, and we certainly need to be prepared for that, we also have climate change impacts that we need to be considering over the next while as well,” Mason says.

Based on reports she has read, she notes that by 2050, the “potential impacts” of climate change “include things like snow pack that is decreased as a result of the warming, high-intensity rainfall events, which could increase the frequency and magnitude of river flooding, and storm surge events.”

On top of that, drier summers could increase wildfire risk in the Vancouver area, Mason adds. There are more people in the woods, and “more people doing activities that could cause fires in the woods and so we have to be prepared to respond together to events such as wildfire risk,” she cautions.

Another hazard to municipalities north of Vancouver is debris flows, “which is a form of channelized landslide, so it eventually comes down the channel of a steep mountain creek, and it usually occurs when there is wet weather and abundant debris, logs, rocks, soil, etc.,” Mason reports.

These landslides can reach speeds of 40 km/h, she says, adding that both the district and the city of North Vancouver are responding to this challenge by installing nets, which are designed to catch debris and stop it from destroying homes or injuring people.

In addition, the District of North Vancouver is working on “development permit areas” for creek hazard, slope hazard and wildfire hazard. This means builders could be prohibited from developing, “or you would have to do specific things for you to be able to develop in those areas,” Mason explains.

STRUCTURAL APPROACHES

Bylaws prohibiting development in areas prone to such hazards are known as “non-structural” approaches, Stevens says, while “structural” approaches to flood hazard include such things as dams and dikes.

“Over time, society in general, in particular researchers, have come around to some of the limitations and weaknesses in the structural approach and some of the advantages of the non-structural approaches, such as land-use planning that actually identifies the hazardous areas and then tries to steer the development away from those areas to safer locations,” Stevens says.

Stevens recently co-wrote a paper – Multi-Level Governance of Flood Hazards: The Case of Municipal Flood Bylaws in British Columbia, Canada – which was published in the February 2014 issue of Natural Hazards Review. His fellow author was Stephen Hanschka, floodplain manager for Clackamas County near Portland, Oregon.

Hanschka and Stevens analyzed the content of 55 mun
icipal bylaws in British Columbia to determine “the extent to which they are consistent with the guidelines and other best practices” in managing flood risk.

“In most cases, they say things like, ‘If you are building in this area, you have to do these certain things,'” Stevens relays. For example, some municipalities will require buildings to be elevated, or that buildings be set back a certain distance from waterways.

In general, he notes, municipal bylaws in British Columbia “require builders to do things to reduce risk, but they don’t generally go so far as to actually prohibit development.”

By comparison, Stevens says that in the United States, municipalities must enforce development standards that would reduce flood risk if they want to join the National Flood Insurance Program (NFIP). Under the program, coverage is written by private-sector insurers, but the rates do not differ among carriers and agents. In some cases, the premiums are subsidized. Only properties in municipalities participating in NFIP are eligible for coverage.

Canada has no such program, but that could change. The federal government announced February 13, in its budget documents, that it plans to “consult with the insurance industry, provinces and territories, and other stakeholders to explore options for a national approach to residential flood insurance in Canada and insurance issues arising from natural disasters more generally.”

It is not clear if such a program would require development restrictions similar to those imposed south of the border by NFIP.

However, most researchers “are on board with the idea that in order to be eligible for disaster assistance, you should be doing something to actually reduce risk at the local level,” Stevens suggests.

“Municipalities and other levels of government have a lot of problems they have to deal with, and historically speaking, natural hazards have kind of been at the bottom of the list,” he points out. “Governments tend to care more about economic development and issues like crime and education and so forth, so natural hazards have sort of taken a back seat.”


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