Raphael Lopoukhine. North Shore News. North Vancouver, B.C.: March 23, 2007. p. 3

Are we planning for climate change?

'Once-in-a-lifetime' weather events are likely on the rise

One year after the 2006 windstorm, District of North Vancouver council listened to residents from Moyne Drive in West Vancouver denounce Capilano Suspension Bridge's plans for more development on the west side.

The turnout and the condemnation might not have been as strong had the residents not lived through three months of heavy trucks and big machines entering and exiting their single-family neighbourhood to clean up major damage caused by the wind storm within the boundaries of the popular tourist attraction.

John Stibbard, son of the owner of Capilano Suspension Bridge, acknowledged to council that the heavy traffic servicing the west side of the tourist attraction was not the norm.

Stibbard said the Nov. 27, 2006, wind storm, the same destroyer-of-Stanley-Park wind storm, had blown a 250-foot tall, 36-ton tree right on top of the suspension bridge. The bridge had to close for 109 days to remove the tree and fix other damage sustained from the more than 100-kilometres-an-hour winds.

It required engineers, contractors, labourers, heavy equipment, massive amounts of concrete, new cables, a bridge anchor and lots of wood.

"This once-in-a-lifetime storm repair is why Moyne Drive residents saw so much heavy traffic," Stibbard said.

The "once-in-a-lifetime storm" was to blame, but climate experts are now saying such a once-in-a-lifetime storm will be more likely to occur every 25 years. As a result, warn the climate impact experts, planners need to start factoring climate variability into all their planning.

As costs mount from today's extreme weather events, actions by local and regional planners are underway to adapt, but a dearth of definitive regional science about future expectations makes planning tough. What was certainty, has been replaced by uncertainty and incomplete data.

In 2007, the Intergovernmental Panel on Climate Change, the United Nations body set up to review all the available literature on climate change, said it was "very likely" that human-released greenhouse gases had already warmed the planet, on average, 0.75 Celsius.

Some of the strongest signals of the change in the region have come in the form of extreme weather events. Generally, a warmer planet means more water is evaporated into the atmosphere, creating more energy to transform into higher intensity storms. The Lower Mainland, though prone to weather variability, has in the past few years been exposed to some extreme weather events, inconveniencing many like the suspension bridge owners and their Moyne Drive neighbours:

- In May 2002, high snow packs and rapid melting, coupled with high rainfall brought flooding and severe runoff throughout many areas in British Columbia.

- In October 2003, a storm system brought strong rains and flooding, described as the heaviest in 100 years, dumping 500 millimetres of rain in an eight-day period.

- At 3:15 a.m. on Jan. 19, 2005, a landslide in the Blueridge area of North Vancouver destroyed two homes and killed one person. Three hundred and twenty millimetres of rain had fallen in the previous 48 hours.

- In January 2006, the record for the number of days of rain in one month was broken.

- Between October 2006 and January 2007, five major storms battered the West Coast, including the one that damaged Stanley Park and Capilano Suspension Bridge. There was also a boil-water advisory, which was brought on by 150 mm of rainfall in one 15 hour period. (The intense rain caused erosion, raising the level of turbidity in reservoir water and negating the disinfecting power of chlorine.)

All the events had an economic impact, although the wind storm likely wrecked the most havoc over the largest area.

Eighty per cent of the District of North Vancouver's land is forested, including a large amount of urban forests. The district has spent $1.1 million on clean-up to date and is still working on restoration projects. It was the most expensive clean-up on the North Shore, said director of engineering Jozsef Dioszeghy.

The much smaller City of North Vancouver was lucky and incurred a minimal cost, said its director of engineering, Steve Ono. The 2006 storm clean-up for the District of West Vancouver "required attention almost to mid-year and redirection of budgets to achieve mid-year-end balance," said their 2008 budget documents.

The greatest regional economic impact was felt by BC Hydro -- and ultimately its customers -- which got hit with a $36.7-million repair bill, while an estimated 1.6 million residents experienced power outages during the storms.

The winds have been lighter so far this winter, but the North Shore has experienced 11 days of snow, an above-average occurrence. The District of North Vancouver ran their 13 big snowplow trucks around the clock and spent $450,000 on snow removal and clean-up, said Dioszeghy.

Like many municipalities in the region, the district was also forced to pay inflated costs for salt because of a regional shortage.

"At one point we had to truck in salt from Alberta, and of course the cost was two to three times higher," said Dioszeghy. "We know for an average winter how much salt we will need and the market determines the price we pay."

West Vancouver reported in their budget documents that the "weather had a big impact on operational, maintenance, and projected costs and scheduling."

There is no categorical proof that human-induced climate change was responsible for all of these events, nor has it been shown in a regional context how many more "out of the ordinary" events we might expect in this region. But there is evidence to show that such events are on the rise.

"We are heading in that direction," said Environment Canada climatologist Bill Taylor -- who responded to questions after they were first sent to Ottawa for approval under new public-relation guidelines for Environment Canada scientists.

Taylor said current global climate models average all the climate variables into a 300-400 square-km space, while regional models work at a 40-50 square-km level. To determine local climate, you would need a much finer scale with better variables than currently exists: more and better weather stations, a team dissecting the local physics of the atmosphere and the land, and a small army of computers to churn out the data, said Taylor.

What remains is to look at what the global climate models predict and what recent trends have shown.

"There is quite a bit of evidence to show that since the mid 1970s there has been an increase in the 'severe storm' category and that when you look at the climate models they also predict or project an increase in severe Pacific storms," said Taylor.

The global climate model also predicts that as well as increased winter storms and rainfall, sea level and temperature will rise. These mega impacts -- storms, rainfall, sea level and temperature -- are like the tip of an impact iceberg. Underneath lies a whole world of interwoven cumulative impacts, whose predictability and certainty is unknown.

"If you add all those thing up, it could spell a lot more risk, said Trevor Murdock, climate scientist and associate director of University of Victoria's Pacific Climate Impacts Consortium. "It's not about predicting everything that happens, it's about narrowing down that range that we have enough of an idea of the things that we can do differently."

Some work by planners has begun as result of the recognition of the changes that are underway.

BC Hydro woke up to the vulnerability of their system after the windstorms. The corporation plans to spend between $225 million and $250 million over the next four years with the intent of reducing the length of each outage while tightening their lines of communication and emergency drills, said BC Hydro community relations co-ordinator Charlotte Bemister in an e-mail.

After the landslides, the District of North Vancouver embarked on a process to determine what level of tolerable risk is acceptable to the community, while also assessing what areas are at risk. The municipality has also begun developing a system to monitor debris flow during spring melts.

Metro Vancouver is expecting to push up their timetable to increase the region's water capacity to offset the expected drier summers, including a second intake system on Coquitlam Lake along with the associated transmission and treatment facility, said Metro Vancouver senior engineer Stan Woods. The Seymour Dam will likely be raised to increase storage capacity by 2040, 10 years ahead of schedule said Woods.

While today's scientists are standing on the tip of the climate-change iceberg with an idea of what's underneath, those who do the planning based on their scientific findings are in some cases waiting for the full diagnostic report before any major overhaul gets underway.

Planners in some cases shouldn't be waiting for a definitive answer, said Stewart Cohen, Environment Canada scientist with the adaptation and impacts division, who is currently seconded to the department of Forestry at the University of British Columbia.

They should begin to expect that the 2006 wind storm will occur something like every 25 years instead of the 100-year norm, said Cohen.

"What kind of actions need to be taken to prepare Metro Vancouver for this kind of event occurring three or four times more often over a period of decades than today?" asked Cohen.

Critics of climate impact research say you shouldn't bother until you have a better idea where emissions will stabilize because you will just be wasting your money on things you may not need.

"I actually think that people talking about adaptation diverts us from the real task at hand. It is kind of like a defeatist strategy in my view," said Mark Jaccard., a professor and climate change economic modeller at Simon Fraser University. "We're sitting here right now facing some huge uncertainties about possible impacts . . . so the probability of spending that money correctly is actually very low."

However, impact scientists say that even if we cut all emissions today, the Earth's climate would still need centuries to stabilize to a predictable level. So even if the world slashes emissions and stabilizes the amount of carbon dioxide in the atmosphere, certain impacts will occur. The trick for climate impact scientists is showing planners that all future scenarios involve change -- some more extreme than others.

"We are heading in a particular direction because CO2 shows no sign of slowing down, and we use models to try to visualize where that is taking us, said Cohen. "The last thing you want is to make a leap and find yourself having designed something that didn't work for the climate that evolved."

Climate-impact scientist Murdock said his team is working to develop scenario information to be used by local planners, but there is a lot of work waiting to be done.

"The theoretical barriers are not the problem," said Murdock "The bottleneck is doing the work."

There is a lot of work because our cities were built expecting a certain climate. Now those expectations have been turned on their head and replaced with uncertainty and incomplete data.

"When you look at things like building design, building codes and engineering design and that sort of thing, we really base it on the past climate, snow, roads and other issues -- we look to history," said Environment Canada's Taylor.

"Historical trends analysis should not be used directly as a basis for future planning, but rather to give context," said Murdock.

Looking to history was the approach taken by the engineering firm BGC Engineering in their landslide assessments conducted for the District of North Vancouver. The landslide hazard assessments were commissioned after the January 2005 Blueridge area landslide as part of the district's natural hazard management program.

BGC used the range of climactic conditions from the past 50 years to assess the level of risk. Yet today it is known that 50 to 85 per cent of precipitation trends at this latitude are due to climate change. Winter and spring total precipitation is expected to increase, and the trends demonstrate that the largest increase in the region has been on the North Shore, said Murdock.

In general, climate change is something BGC is examining in the abstract. BGC engineer Matthias Jakob recently penned a paper that has now been submitted for peer review on climate change impacts on landslide risk. It concluded that it was "reasonable to expect that landslide frequency along the south-west coast of B.C. will increase during the 21st century."

As for incorporating that knowledge into present landslide risk assessments, Jakob wrote in an e-mail which was also forwarded through district staff along with a copy of his report that the changes "will be relatively subtle and extremely difficult to include in a quantitative sense."

Murdock expects that his consortium over the next three to four years will be looking at how to quantify the expected increase in landslide risk for the on-the-ground assessments.

"We haven't had the resources yet, or I would put it as it hasn't been done yet," said Murdock.

Metro Vancouver contracted Murdock's group, Pacific Climate Impacts Consortium, to update the region's future precipitation predictions to determine if larger sewers were needed to handle the expected increase in rainfall. Despite demonstrating a six per cent increase in total precipitation, coming in larger and more intense events, Metro decided not to increase the size of the sewers, whose lifespan is roughly 75 years.

"Based upon available data, they (PCIC) couldn't make a firm statement that this result is necessarily because of anthropogenic climate change. Other natural climatic cycles, such as the El Nino Southern Oscillation and the Pacific Decadal Oscillation, also appear to play a significant role in influencing local climate," wrote Metro Vancouver planner Albert van Roodselaar in an e-mail response to questions.

Meanwhile, Murdock repeated that more specific work downscaling from the global climate predictions to create more precise projections of future extreme precipitation would help with planning. Even though he doesn't know the specifics around the decision not to boost capacity, he thinks an integrated assessment with planners, engineers and climate scientists would be the best approach in making these types of decisions. He is surprised planners didn't hedge their bets a little.

"Decision-makers are generally uncomfortable with this level of uncertainty. We really need those downscaled projections of extremes. But while we develop those over the coming years, I would think that one might still be able to hedge bets slightly," wrote Murdock in an e-mail response.

Another question around storm sewers is whether bigger is even better. Should rainfall be managed before it hits the sewer system. Going with a more sustainable-minded approach is an alternative worth factoring into the integrated discussion, said Environment Canada's Cohen.

"Rather than replacing a 20-centimetre pipe with the same pipe, maybe that gets replaced by something different," said Cohen, who is pioneering integrated assessment work with Okanagan planners and helping to establish stronger controls to mitigate climate change-caused future water shortages.

The City of North Vancouver has an innovative example of a sustainability-minded storm-water management system at the corner of Lonsdale Avenue and 21st Street. A couple of planters in the middle of a newly built bus bulge capture rainwater runoff before it ends up in the sewers. The city has been pursuing alternative drainage methods for around 10 years, said Ono.

It is unknown what the cost would be to adding sustainability and climate variability in the redevelopment of infrastructure. It would no doubt, in the short term, add to the already inflated Federation of Canadian Municipalities' estimated $123 billion price tag to replace the nation's infrastructure. Nevertheless, Cohen says it's necessary and needed.

"It's an actually an opportunity," said Cohen. "If there is political support for infrastructure renewal, then this is a great time to inject climate change as a factor."

© North Shore News 2008