SOMBA K'E/YELLOWKNIFE - The delay in replacing a dam in imminent danger of collapse at the Bluefish hydro site could lead to a "significant" increase to power bills, according the NWT Power Corporation.

Despite the urgent need to replace the 60-year-old Bluefish dam, Power Corp. has delayed the project a full year because it didn't have time to supply its construction site. Warm weather forced the closure of the winter road to the facility across Prosperous Lake on April 7, said Mike Bradshaw, director of corporate communications with the NWT Power Corporation.

It was only last September that Power Corp. was threatening legal action against the Mackenzie Valley Land and Water Board if it did not approve the $17-million project immediately. It warned the dam's collapse was "imminent," and that it could not "accept any delays or disruptions which may arise due to any matters."

Yellowknife gets most of its hydro power from the Snare River, but Bluefish, which was sold to Power Corp. by Miramar Mining in 2003, supplies about 7.5 megawatts. The Snare Hydro plant can provide a maximum of 21 megawatts of power, so having Bluefish up and running is imperative during peak power usage, which usually occurs in the coldest winter months when usage can reach 30 megawatts, Bradshaw said.

The land and water board granted an emergency exemption for the project on Oct. 7, stating in a letter it was "persuaded that there are limited options available for (the corporation) to respond to the unexpected and accelerated deterioration of the dam over the last year."

Bradshaw said while the corporation was able to get some of the supplies to the site during a month-long period between early March and April, including those for a 50-person camp, fuel tanks and a water and sewage treatment facility, the corporation was unable to get heavy equipment like back haul trucks, heavy graders and 30,000 square feet of sheet pile - weighing in the hundreds of tonnes range - to the site.

Despite the warmer than usual winter this year, the three diamond mines using the Tibbitt to Contwoyto winter roads managed to transport 3,506 loads weighing 121,000 tonnes in less than two months before that road shut down for the season March 24.

On Wednesday, Bradshaw e-mailed to say that power customers could pay a lot more on their bills if the dam fails.

"The impact on rates is approximately one cent per kWh," Bradshaw stated, referring to the rate rider the territorial government-owned company plans to charge customers to pay for the project.

"The rate impact rises dramatically if the old dam fails and we're forced to replace hydro with diesel generation. The cost of diesel fuel alone would be $7 million per year."

Bradshaw said if the dam fails before Power Corp. can replace it, the company will have to build a new diesel plant at Jackfish Lake to provide more power to the city. He predicted the current plant at Jackfish would take a beating because of its infrequent use.

"We'd see some serious wear and tear on the diesel generators there now because they are only on for a few hours a year," he said, adding the impact on customers would be "pretty significant."

Bradshaw said the corporation is looking at other options to get some of the equipment and materials out to the Bluefish site by barge, but he said it's an uphill battle.

"It's looking like a long shot right now," he said of shipping the remaining supplies by water to the site, some 20 km outside the city.

Bradshaw said the dam is holding up, so far.

"We're doing a lot of site monitoring daily, plus there is 24-hour surveillance," Bradshaw said. "The snow pack this year is down, it's below average, so we're hoping the run off isn't going to cause any problems. So far it's looking pretty good."