Image from a new report on sea level rise from the City of Campbell River.

Seawater could eventually cover downtown Campbell River due to climate change-fueled floods

City planning for long-term flood mitigation as rising seas threaten buildings and infrastructure

Higher sea levels driven by climate change could cause extensive flooding in coastal areas of Campbell River by 2100, and plans are underway to reduce the risks, according to a new report from the city.

Municipal officials organized two workshops last week to field questions from the public about the findings, and to get feedback about how to adapt to changes on the coastline.

Flood mitigation infrastructure will develop gradually, said Amber Zirnhelt, the city’s manager of long-range planning and sustainability.

“It will be long-term, slow process,” she said. “We’re not talking about tomorrow going and building a big seawall along Campbell River.”

The two-part report describes a number of practices used around the world to deal with sea-level rises, ranging from offshore reefs to seawalls to homes elevated on piles.

David Reid, an architect working with the city on sea-rise planning, described some of the pros and cons of those techniques during a presentation at Willow Point Hall on Nov. 29. Dikes, for example, tend to block the scenery.

“If your house is low and the dike is high, then you can’t see the view anymore, which is highly undesirable,” Reid said.

And more importantly, dike failures can lead to widespread deaths, something that’s occurred in the Netherlands, he said. For that reason, policymakers frequently ask people to sleep at a level higher than the crest of the dike.

“If the dike fails, we don’t want you to die,” Reid said.

READ MORE: Even oil companies admit that CO2 emissions cause climate change

It’s the kind of consideration that more coastal communities will be wrestling with as they plan for the future.

Sea rise is practically inevitable, said Grant Lamont, a coastal engineer with Northwest Hydraulic Consultants, which was hired by the city to study ocean dynamics.

“There’s less and less uncertainty today within the scientific papers and scientific community that sea-level rise is going to happen,” he said. “The uncertainty is about when.”

The flood projections are based on a one-metre rise in sea levels by 2100 in combination with elements including a major storm event, king tide, storm surge and wave action, Zirnhelt said.

READ MORE: ‘Bit frightening:’ Study finds most Canadian cities fail on climate change plans

The report indicates that if nothing were done to prepare for that kind of scenario, water would flood a large section of downtown, stretching across the lower parts of Hwy. 19A, Dogwood St., Shoppers Row and other streets.

Water would also hit various public works, including communications and electrical utilities that run underground. The downtown fire hall would also be affected.

In Willow Point and south – an area “very exposed to high storm winds and waves from the open reaches of the Strait of Georgia” – water would hit various utilities and the lower floors of some buildings and low yards. The boat ramp would be at risk, along with the grounds and boathouse of Sybil Andrews Cottage.

Surging seas would squeeze out habitat and walking areas along the foreshore, and rock armouring would be at a greater risk of “failure or overtopping due to increased wave height,” according to the report.

Elsewhere in the city, public beach areas at Sequoia Park and nearby low-lying buildings and parking areas would also be affected by rising seas, and sanitary gravity sewers would be at risk.

Erosion may also affect the stability of steep slopes along the stretch of coastline between Evergreen Rd. and the Maritime Heritage Centre.

READ MORE: UN chief issues dramatic climate appeal to world leaders

In North Campbell River, key risks include water hitting the lower floors of several buildings in the Agricultural Land Reserve along with damage to pocket beaches and sensitive shoreline areas.

The bluffs area would also be at risk of erosion and slides, which could in turn threaten the sites of existing homes, along with utility and stair routes.

The report notes that greenhouse gas emissions due largely to human activity are the primary driver of sea-level rise, as higher temperatures cause thermal expansion of ocean waters and accelerated melting of ice sheets and glaciers.

In Campbell River, the effect of rising oceans is checked somewhat by a slight upheave of the area’s land mass, but “sea-level rise is happening faster than the land is rebounding,” the report states.

The one-metre figure comes from provincial guidelines based on projections from the UN’s Intergovernmental Panel on Climate Change (IPCC), which brings together experts from around the world to assess published literature about climate change and to provide information to governments.

Several governments are already planning for a 1.6 metre rise, and B.C.’s one-metre figure may be revised upwards as new information becomes available, Zirnhelt said.

“We have to plan with that factor of uncertainty in mind,” she said.

@davidgordonkoch
david.koch@campbellrivermirror.com

Like us on Facebook and follow us on Twitter

Just Posted

North Saanich Fire Department wins national Movember challenge

Team raises more than urban Edmonton, Toronto firefighters

Province launches lawsuit over Esquimalt sailing incident that killed teen with disabilities

Gabriel Pollard, 16, died from injuries after being dropped from marine lift in 2018

Saanich police first in B.C. to offer mental health resiliency training

Departments from Oak Bay, Saanich, Central Saanich complete trauma training class

Peninsula Panthers jump into first place with win over arch-rivals Victoria Cougars

Cougars beat the Panthers in all three previous games before Sunday’s 2-1 victory

Crash backs up northbound lanes of Pat Bay Highway

Drive BC warns of heavy congestion along busy route

VIDEO: Kenney lays out key demands for meeting with Trudeau

Alberta Premier Jason Kenney aims for clear signs of federal action on two-day Ottawa trip

First Nations want Big Bar landslide cleared ASAP to allow fish passage

Leadership calling for urgent action and resources to remove obstruction on the Fraser

Assessed value of Lower Mainland homes expected to decrease in 2020

Other areas of province may see modest increases over last year’s values

Chilliwack family’s therapy dog injured in hit and run

Miniature pit bull Fifty’s owner is a single mother facing close to $10,000 in vet bills

Cougar destroyed in Penticton area after mauling dog, killing cat

This is the first reported incident with a cougar this year in the Penticton area

Feds not enforcing standards on Hungarian duck imports, B.C. farmer says

‘You have no way of knowing what’s in the bag’

No reports yet of Canadians affected by New Zealand volcano eruption, feds say

Missing and injured included tourists from the U.S., China, Australia, Britain and Malaysia

Vancouver Island blues musician’s mother’s home burglarized and ransacked

David Gogo’s 71-year-old mother has jewelry and artwork stolen in break-in

Dance cancelled after Alberta teacher’s climate lesson prompts online threats

School district near Red Deer cancelled annual family dance due to Facebook comments

Most Read