Hundreds of aging B.C. dams pose safety risk

Three out of every four dams in B.C. will be more than half a century old by next year -and an increasing number of them will have been abandoned by the private licence holders who are responsible for their maintenance.

That's a scary combination, says a report from a parks and rivers watchdog group, because the life expectancy of an unmaintained dam is about 50 years.

There is a "growing number of potential problems that are likely to arise from dam structures that will have reached the end of their life cycle or that are likely to be abandoned due to the costs associated with upgrading," says the report, published in 2001 by the Outdoor Recreation Council of BC.

"There is a legitimate concern about the limited human, technical, and financial resources that are currently being allocated to the existing management of our dams."

The issue of dam safety in B.C. has been in the headlines since an 80-year-old dam at Testalinden Lake failed on June 13 and sent a flood of water and debris down a slope, wiping out five homes near Oliver and forcing many more residents out of their homes. The dam is one of 1,985 registered in the province.

The B.C. government declined to comment on the report, River Recovery: Restoring rivers and streams through dam decommissioning and modification.

At the time it was written, in April 2001, the authors said about half of B.C.'s dams were at least 50 years old, and by 2011 three-quarters of them would be a half-century old.

The report also estimated that as of 2001, roughly 100 dams had been abandoned in B.C., and about 10 per cent of those were "considered a liability to people, property and to the ecological health of our rivers."

The report, which was completed in the dying days of the NDP administration, said the environment ministry of the day had removed or safeguarded nearly half of the abandoned dams.

However, report administrator Mark Angelo, who was then chair of the Outdoor Recreation Council, believes even more dams have since been abandoned and said it is unclear what has been done to safeguard their upkeep because the Liberals have reduced the environment ministry's budget.

"I suspect there may well be other dams out there that are not getting the maintenance they need," said Angelo, now with the BCIT Rivers Institute.

"The maintenance is the responsibility of the licence holder, but obviously the government has a key role to play as well in auditing that activity."

The report called for decommissioning some dams -- either because they are no longer used for their original purpose or they are decaying -- to improve public safety and return rivers to their natural state.

Rick Simpson, who contributed to the report, said the 2001 document identified several provincial-government funds that could finance work on dams, but those funding sources now no longer exist.

"Since they've vanished, the chances of focus on some of the priorities in the report seems really highly unlikely," said Simpson, volunteer co-chair of the B.C. Wildlife Federation's Okanagan-Similkameen fisheries committee.

Among the hundreds of reports written this decade by engineers for the Canadian Dam Association, one noted that "many of the small irrigation dams in British Columbia have been in service for more than 50 years," and another agreed the "aging phenomenon" of dams accelerates after 50 years.

A 2002 report sponsored by Environment Canada and written by a New Brunswick river watchdog group, noted there is "a large number of small abandoned dams that have outlived their intended purpose. These dams were built at times more than 50 or even 100 years ago and in many cases their owners cannot be identified."

The report, Reclaiming Free Flow: An Information Guide on Removing Small Abandoned Dams, said B.C. was one of only two provinces with audits to assess dam safety, which led to the recent decommissioning of the Theodosia dam near Powell River.

B.C.'s environment ministry is now performing "rapid assessments" -- mostly from the air -- on every dam in the province following the Testalinden Lake dam collapse, and as a result a spokesman said staff were too busy to answer The Sun's questions about the findings of the Outdoor Recreation Council report.

The ministry cited the same reasons last Friday, when it declined to reveal how many mandatory audits have been completed on B.C. dams.

Rules established in 2003 require the ministry to audit every 10 years the maintenance done by the private owner of the Testalinden Lake dam. The dam was deemed to be of low risk to cause damage to property, people or the environment in the event of a failure.

More than 300 of B.C.'s 1,985 dams are classified as high or very high risk -- meaning their failure would cause significant fatalities, economic losses or environmental damage. Just over half of those 300 dams are under nine metres in height and are often used by farmers, while the rest are taller than nine metres and are typically used by governments or corporations such as BC Hydro.

Last week's devastating incident is being investigated by the Ministry of the Solicitor-General.

lculbert@vancouversun.com