March 12, 2015 by Canadian Underwriter
Nearly two years after floods caused Canada’s costliest natural disaster, Alberta’s Office of the Auditor General has found that the province’s environment and sustainable resource development (ESRD) department produces “technically sound flood hazard maps,” but those maps are not always up to date and the department lacks capacity to assess flood risk.
Risk from oil and gas pipelines was another concern cited by the March 2015 Report of the Auditor General of Alberta.
The Alberta Energy Regulator “does not have a structured process to identify, rank and target key pipeline operational risks, and integrate them into the operational plan,” Auditor General Merwan N. Saher stated in his report released to the legislature earlier this month.
“Pipeline failures can be caused by construction damage, damage by individuals, earth movements, internal and external corrosion, joint failure, overpressure and operator error,” Saher wrote. “These failures include leaking (a pipeline is losing product but continues to operate) and rupture (a pipeline cannot continue to operate).”
ESRD, which is responsible for flood mitigation in Alberta, “does not have historical information on the consequences of previous floods, such as lives lost, injuries, property damage and business interruption,” according to the report.
In June, 2013, floods in southern Alberta gave rise to about $1.7 billion in insured losses, exceeding those of the 1998 ice storm in Eastern Canada.
As a results of the 2013 floods, Saher noted that five people lost their lives, rebuilding costs were estimated at more than $6 billion, about 14,500 homes were damaged and more than 1,500 businesses were disrupted.
ESRD “produces technically sound flood hazard maps,” according to Report of the Auditor General of Alberta. “However, the department’s mapping guidelines have not been updated to deal with all types of flood hazards. The guidelines cover flooding caused by overland flow from a water body (such as a river or lake) caused by excessive flow or an ice jam. They do not cover geo-hazard events such as debris flows or debris floods or the risk that erosion and rapid channel change will cause flooding.”
As of last September, ESRD created 63 maps. Forty-eight of those, covering 960 kilometres of river, “are finalized,” the OAG wrote.
“A recent review of Canadian floodplain mapping programs estimates that Alberta requires another 770 kilometres of river mapping to document its flood hazard areas.”
The auditor general recommends that ESRD map flood areas that are not currently mapped but are at risk of flooding. He also recommends the department update and maintain its flood hazard maps and update its flood hazard mapping guidelines.
“The department uses the 100-year flood as the benchmark for floods and water elevation increases,” Saher wrote. “To create a flood hazard study, the department assesses the river system’s stream flow data and historical flood records. The outcome of the study is a report and a flood hazard map showing the flood hazard area.”
The hazard maps, he added, are divided into floodway and flood fringe zones.
The floodway typically includes the river channel and adjacent overbank areas of the design flood where flows are deepest, fastest and most destructive. Those are areas where:
-water is one metre deep or greater;
-local velocities are one metre per second or faster; and
-the water level is 0.3 metres or more above normal.
Flood fringe is land “along the edges of the flood hazard area not included in the floodway.”
“In 2013 the Municipal Government Act was changed to allow the Government of Alberta to make regulations to control, regulate or prohibit any use or development of land in a floodway,” Saher stated in his report. “The Department of Municipal Affairs is working on the Floodway Development Regulation to limit property damage and risk to public safety from future floods within a floodway. Once complete, the Department of Municipal Affairs needs to establish systems to implement and enforce the regulation.”
The floods in June, 2013 “began when a slow, intense low-pressure weather system delivered 80 to 275 mm of rain to the eastern slope of the Rocky Mountains, causing the Bow, Elbow, Highwood and other rivers to overflow their banks,” according to the March 2015 Alberta Auditor General’s report. “The flooding across southern Alberta affected an area of 55,000 square kilometres. Significant damage occurred to roads, critical infrastructure and public facilities.”
Regarding pipelines, Saher recommended the Alberta Energy Regulator “complete a skills gap analysis and formalize a
training program for its core pipeline staff.”
Pipelines “carry materials that can cause environmental damage and health and safety issues. In recent years, significant pipeline failures have also led to increased public concerns over the safe operation of pipelines,” he wrote. “Although the probability of a single failure is low, each critical event has a potential for high impact and consequence to public safety and the environment.”