Power line work stops until young hawks can take flight 

When a pair of ferruginous hawks decided to nest in the only tree standing in a sea of rolling southern Alberta grassland, it was tools down for Enbridge.

The tree was located within one kilometre of a company work site, south of Lethbridge, so Enbridge officials waited about a month for the hawks, classified as a species at risk, to raise their three fledglings.

As a result, Enbridge’s new $300-million transmission line will begin importing Montana wind power into the province next week, missing their end of July target.

“These birds are a protected species and were actually following the crews as they installed the line,” said Don Thompson, vice-president for green energy at Enbridge.

“We were basically feeding them, because the work crews stirred up the field mice,” he said.

“You would think the sounds of construction would disturb the hawks, but these birds are predators and they are looking for any advantage. And we gave them lots of advantages.”

Things went along smoothly until June.

“They were all fattened up and thought that now it was time to lay the eggs. And there was only one tree within a kilometre of our site, so they moved in,” said Thompson.

Enbridge biologists were aware the hawks had been following the crews, and when the birds began to nest, the company shut down nearby operations.

“We couldn’t erect transmission towers there, so we worked around them and completed the balance of the line outside their zone,” said Thompson.

Finally, on July 16, company and Alberta Environment biologists confirmed the birds had left the nest with their young.

“You know the fledge has happened because right after, the ravens moved in. They take over abandoned nests.”

Thompson said Enbridge had hoped to build the Alberta section of the line during the winter of 2012, but didn’t receive approval until December.

“However, this kind of thing is not unusual for us. We have this interaction between wildlife and the environment with our lineal construction. It doesn’t matter if you are building pipelines, wind farms or power lines.”

Enbridge shut down work at its Cedar Point wind farm in Colorado recently when golden eagles set up a nest within one kilometre of a turbine. Construction resumed when the birds moved on.

Rust-coloured ferruginous hawks like the arid, open grasslands and feast on ground squirrels, mice and even insects like grasshoppers. They also take down grouse and ducks, and are used in falconry. The hawks will nest in just about any spot with a view, from ledges and power poles to haystacks or isolated trees which give them a clear view of their hunting range.

In Alberta, their population dropped below 1,000 breeding pairs by 2005 and they were classified as threatened, but the situation has improved and they are currently a species at risk.

While best known as an oil and gas pipeline operator, Enbridge has branched out into green energy in the past decade, spending more than $3 billion on renewable and alternate energy. With 1,600 megawatts of capacity, the company is now Canada’s largest producer of wind and solar power.

The soon-to-open 340-kilometre transmission line runs between Great Falls, Mont. and Lethbridge.

Called the Montana-Alberta Tie Line (MATL), it is Alberta’s first direct link to the U.S. and the only private or merchant line in the province. It will operate like a pipeline, with Spanish-owned wind energy firm Grupo NaturEner supplying the power from its 189-megawatt Rim Rock wind farm near Kevin, Mont.

Enbridge bought the partially-completed transmission project from Tonbridge Power in 2011. The electricity is sold to Morgan Stanley Capital Group through a power purchase agreement that also includes the environmental green credits needed by San Diego Gas and Electric. It is the same kind of arrangement that made Alberta’s two recent wind farm projects economically possible in the province’s open marketplace.

The addition of up to 300 MW of Montana wind power is not expected to affect Alberta’s power prices, says the Alberta Electric System Operator (AESO).

Montana has the best wind resource in the U.S. but it has very limited connections with other states, which makes the Alberta marketplace a logical destination for its green energy.

In May, Grupo NaturEner announced two large wind projects for the Medicine Hat area, and these will be entirely market-based and not have the advantage of a subsidy from U.S. green credits.