Observed versus modeled flow of the Athabasca River at Athabasca over the calibration period (1952−2010) for five tree-ring models (described in Table 2 and Table S4). Graphic: Sauchyn, et al., 2015 / PNAS

By Emily Chung
21 September 2015

(CBC News) – The river that provides water to the oilsands industry is much more prone to multi-year droughts than modern records show, suggesting that the industry's current level of water use may not be sustainable, a new study suggests.

The oilsands industry needs 3.1 barrels of fresh water to produce a barrel of crude oil from oilsands mining, according to the Canadian Association of Petroleum Producers.

That water for oilsands mining comes mainly from northern Alberta's Athabasca River, and oilsands account for 72 per cent of estimated water use from the river.

The government regulates the amount of water the oilsands industry is allowed to use based on measurements of water flow taken by dozens of monitoring stations along the river since 1957.

But a study led by University of Regina researcher David Sauchyn has found that those water flow measurements aren't that representative of the river's long-term behaviour.

"What we show is if you go back 900 years, the river is much more variable than you would think based on measurements since 1950s," Sauchyn said. […]

What they found were records of droughts that lasted years to decades, including relatively recent severe droughts from 1888-96 and another one from 1790 to 1806, when river flows were lower than the minimum ever recorded by modern instruments.

Some droughts in previous centuries were even worse, lasting up to half a century.

"That is something we just haven't experienced, when we do it's going to be difficult because we're not used to it," Sauchyn said, "but also because it will reoccur in a much warmer climate than in the past — a double whammy." [more]

Oilsands may face severe water shortages, Athabasca River study suggests


By Katherine Bagley
21 September 2015

(InsideClimate News) – The source of water used for drilling in the Alberta tar sands could dry up in the coming decades, according to new research released Monday. The questionable future of the Athabasca River threatens the longevity of fossil fuel extraction in the world's third-largest crude oil reserve.

Scientists at the University of Regina and University of Western Ontario in Canada looked at 900 years of tree ring data and found water levels have dwindled along the 765-mile river at various points throughout its history.

The analysis, published in the peer-reviewed journal Proceedings of the National Academy of Sciences, shows the waterway has shrunk over the past 50 years as global warming has melted the glaciers that feed it. It also found the region has experienced several droughts that have lasted more than a decade in the last few centuries. Such a drought could likely happen in the near future, the scientists said.

"Conventional water management assumes that what you had for river flow the last 50 years is what you will have for the next 50," said Dave Sauchyn, a climate scientist at the University of Regina in Canada and lead author of the study. This short-term data is what officials use to determine how much water tar sands operators can take from the Athabasca, he said. […]

It currently takes as many as  3.1 barrels of water to produce one barrel of crude oil from the Alberta tar sands, according to the paper. In 2012, fossil fuel operators drew 187 million cubic meters of fresh water out of the Athabasca River, equal to 4.4 percent of the river's annual flow and the water usage of 1.7 million Canadians. This amount is expected to more than double in the next decade, to 505 million cubic meters per year, if mining operations expand as expected. […]

This research "clearly demonstrates that oilsands extraction will continue to place significant demands on Alberta's environment," said Erin Flanagan, an expert on tar sands and water issues for the Pembina Institute. "Ultimately, the question to policymakers is around fairness – is it appropriate for oilsands to increase its access to Alberta's freshwater resources as they become more scarce over time?" [more]

Water Source for Alberta Tar Sands Drilling Could Run Dry


ABSTRACT: Exploitation of the Alberta oil sands, the world’s third-largest crude oil reserve, requires fresh water from the Athabasca River, an allocation of 4.4% of the mean annual flow. This allocation takes into account seasonal fluctuations but not long-term climatic variability and change. This paper examines the decadal-scale variability in river discharge in the Athabasca River Basin (ARB) with (i) a generalized least-squares (GLS) regression analysis of the trend and variability in gauged flow and (ii) a 900-y tree-ring reconstruction of the water-year flow of the Athabasca River at Athabasca, Alberta. The GLS analysis removes confounding transient trends related to the Pacific Decadal Oscillation (PDO) and Pacific North American mode (PNA). It shows long-term declining flows throughout the ARB. The tree-ring record reveals a larger range of flows and severity of hydrologic deficits than those captured by the instrumental records that are the basis for surface water allocation. It includes periods of sustained low flow of multiple decades in duration, suggesting the influence of the PDO and PNA teleconnections. These results together demonstrate that low-frequency variability must be considered in ARB water allocation, which has not been the case. We show that the current and projected surface water allocations from the Athabasca River for the exploitation of the Alberta oil sands are based on an untenable assumption of the representativeness of the short instrumental record.

Long-term reliability of the Athabasca River (Alberta, Canada) as the water source for oil sands mining

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