Carrot-and-stick approach to EOR

Gary Park

Petroleum News Calgary correspondent

The use of fresh water in enhanced oil recovery projects should be reduced, but not banned, said an advisory committee report to Alberta Environment Minister Lorne Taylor.

It said an immediate end to the practice would not be a “reasonable response” until a voluntary approach has been tested.

However, if sufficient reductions aren’t achieved through voluntary efforts, the government should impose a “mandatory regulatory requirement,” the 23-page report said.

The committee noted that EOR accounts for more than half of Alberta’s output of conventional light oil and generated C$447 million in royalties in 2001.

Over the past 30 years the use of water for conventional waterflood projects has been shrinking in Alberta due to improved water recycling methods and a decline in the remaining recoverable oil resources in existing conventional EOR projects.

But water use in thermal recovery projects has grown, despite some technological advances in the use of saline groundwater.

Government statistics show that water diverted for EOR use dropped to 47.5 million cubic meters in 2001 from 88.7 million in 1972. The 2001 tally included 37 million cubic meters of “make-up” water, of which 78.1 percent was non-saline.

Environmentalists, farmers and ranchers oppose the use of underground and surface fresh water because it permanently removes that water from the hydrological cycle, especially in recent years as Alberta has been crippled with a series of droughts. Studies show that in the late 1990s rivers in Alberta and Saskatchewan were flowing at 60 percent to 19 percent of their historic levels.

The Athabasca River in northeastern Alberta, the single most important source of water for the oil sands, is declining fast, said University of Alberta ecology professor David Schindler.

He said there are projections that by the mid-2000s the base will be only 80 to 90 cubic meters per second. The current flow is calculated at about 675 cubic meters.

“We’ll see who’s right, but I don’t think it’s right to play Russian Roulette with the system,” he said.

Taylor, while suggesting that wars will be fought over water “as we move forward,” noted that the oil and gas sector accounts for only 4.6 percent of the water licensed for use, yet the industry contributed C$7.2 billion in royalties to government coffers last year.