|credit David Nunuk/Pew Environment Group|
|BC Hydro service area, almost all of the province|
With abundant supplies of water but a need for electricity in growing populations centers, in addition to a few initial coal- and gas-burning power plants, Canadians in the western province of BC turned to an ostensibly "clean" source of energy. The principal electric utility is BC Hydro, officially known as the BC Hydro and Power Authority (BCHPA), created in 1961 and regulated by the British Columbia Utilities Commission as a power (not water) provider. BC Hydro operates 30 hydropower facilities (and shares operation of one more) for 86% of its energy portfolio, supplying electricity to ~1.8 million Canadians over 95% of the province. The following table lists the numerous hydropower operators in BC with some of their infrastructure information, derived from a detailed list of hydropower stations throughout BC.
|Capacity range |
|Total capacity |
|BC Hydro||30.5||1912 - 1984||2.6 - 2730||10,345.6|
|Brookfield Renewable Power||4.5||1911 - 2003||1.5 - 46||113.1|
|Capital Power Corporation||2||1996 - 2003||7 - 33||40|
|Capital Power Income||2||1990 - 1996||5.7 - 52||59.7|
|Cloudworks Energy||6||2010||16.7 - 33.5||151.8|
|Columbia Power Corporation||3||1944 - 2009||120 - 185||450|
|Fort Chicago Energy Partners||3||2004 - 2009||11||33|
|FortisBC||5||1907 - 1993||18 - 66||253|
|Innergex Renewable Energy||3||2004 - 2010||7.5 - 50||107.5|
|Macquarie Power & Infrastructure||2||1997 - 1999||3 - 17||20|
|Plutonic Power||2||2010||73 - 123||196|
|Renewable Power Corp.||2||2004 - 2009||9.3 - 9.8||19.5|
|Summit Power||2||1994 - 1996||5.6 - 14||19.6|
|Synex Energy Resources Ltd||2||2004 - 2009||2.8 - 3.8||6.6|
|TransAlta||2.5||1995 - 2005||10 - 45||47.5|
|Single-facility companies (22)||21.5||1905 - 2009||0.1 - 790||1140.6|
|Total/Composite: 37 companies||93||1905 - 2010||0.1 - 2730||13,003.5|
*values of 0.5 indicate cooperative facilities: the facility at Waneta Dam is shared by BC Hydro and Teck;
the facility at Pingston Creek near Revelstoke is shared by Brookfield Renewable Power and TransAlta.
Buried in that table are some interesting figures. First, BC Hydro's hydropower constitutes just under 80% of all the hydropower production in BC with just about one-third of all the facilities in operation. BC Hydro operates more hydropower facilities than all of the single-facility companies combined, with a total generation capacity more than ten times that of the independent single-facility operators. The single largest hydropower facility in BC is the 2,730 MW Gordon M. Shrum Generating Station at W.A.C. Bennett Dam, built in 1968 on the Peace River and operated by BC Hydro. BC Hydro operates four of the top five and 7.5 of the top ten hydropower facilities (in terms of generating capacity) in the province; one of those facilities is the 490 MW Waneta Dam that is shared by BC Hydro and Teck (hence the 0.5 in my accounting here). The fifth-largest facility in BC is the Kemano Power Station on the Nechako River at Kenney Dam, the largest earthfill dam in the world when it was built in 1953. Kemano is now operated by Rio Tinto Alcan, an international mining conglomerate recently expanded from its global base in South America.
|W.A.C. Bennett Dam and Williston Lake on the Peace River,|
operated by BC Hydro
|Hugh Keenleyside Dam, a run-of-the-river hydropower station operated by|
BC Hydro, and the newer Arrow Lakes Generating Station, owned by the
Columbia Power Corporation, on the Columbia River (Wikimedia Commons)
In 2008, a group of eminent hydrologists declared in the journal Science that "Stationarity is Dead" :
"Stationarity - the idea that natural systems fluctuate within an unchanging envelope of variability - is a foundational concept that permeates training and practice in water-resource engineering...
"The stationarity assumption has long been compromised by human disturbances in river basins. Flood risk, water supply, and water quality are affected by water infrastructure, channel modifications, drainage works, and land-cover and land-use change. Two other (sometimes indistinguishable) challenges to stationarity have been externally forced, natural climate changes and low-frequency, internal variability (e.g., the Atlantic multidecadal oscillation) enhanced by the slow dynamics of the oceans and ice sheets [5, 6]. Planners have tools to adjust their analyses for known human disturbances within river basins, and justifiably or not, they generally have considered natural change and variability to be sufficiently small to allow stationarity-based design...
"Stationarity is dead because substantial anthropogenic change of Earth's climate is altering the means and extremes of precipitation, evapotranspiration, and rates of discharge of rivers [7, 8]. Warming augments atmospheric humidity and water transport. This increases precipitation, and possibly flood risk, where prevailing atmospheric water-vapor fluxes converge ... Glacial meltwater temporarily enhances water availability, but glacier and snow-pack losses diminish natural seasonal and interannual storage ."Their reference numbers (2 - 7) have been converted to my own [5 - 10] and listed below for your ease of searching. One common area in which "prevailing atmospheric water-vapor fluxes converge" is on the seaward side of mountain ranges, as in southern BC on the Pacific side of the Coast Range and Rocky Mountains. BC also hosts massive glaciers subject to thinning and melting, and is anticipated to experience new extremes in precipitation volume and frequency. Most specifically, the group borrowed results of the Intergovernmental Panel on Climate Change (IPCC) 4th Assessment Report (AR4), Contribution of Working Group II (WG2) regarding the impacts of anticipated climate change on freshwater runoff :
We see that BC, and much of Canada, is expected to see generally greater runoff volumes with climate change, though additional factors such as earlier melting times in the year must also be taken into account. An accompanying figure in another part of the IPCC AR4 WG2 report  indicates that forested areas in BC will actually increase in coverage, though some areas in this part of the Canadian boreal forest will change in type (likely from evergreen to deciduous) and the southernmost fringes might dry out and disappear altogether. The evidence of insect infestation and degraded forest area is already well known in the American Rockies and is creeping northward into BC and Alberta, an indication that the health of the forest ecosystem is already under stress and a harbinger of forest succession, potentially including more widespread forest fires. The impacts of these changes could devastate the inherent ecological services of the region, including biodiversity in the boreal and coastal temperate rainforest ecosystems, carbon sequestration in the forest areas, and water quality in downstream areas.
So what do these climate changes mean for water supplies and utility operations in the province? In snow-dominated areas, including some watersheds originating in the Coast Range but primarily those in the Rocky Mountains, Barnett et al. (2005) provided a precise summary of the anticipated impacts :
"In a warmer world, less winter precipitation falls as snow and the melting of winter snow occurs earlier in spring. Even without any changes in precipitation intensity, both of these effects lead to a shift in peak river runoff to winter and early spring, away from summer and autumn... Where storage capacities are not sufficient, much of the winter runoff will immediately be lost to the oceans."On the Columbia River, we might not expect any missed winter and spring runoff to be "lost" given the massive storage capacity of so many dams downstream in the US. In other major basins, such as the Yukon headwaters and on the Peace River, the volume of water is so abundant that the infrastructure seems oriented more on hydropower production and less on freshwater storage, such that the water is generally passed downstream in run-of-the-river project locations. These projects may very well meet the needs of BC residents for the immediate future, but in the long term I can envision calls from outsiders to build and fill additional storage capacity for eventual transfer to the province's northeastern prairie areas and to its neighbors, including Alberta to the east and the US states to the south. These areas are already water-stressed, and the anticipated concentrations of population and industry there over the next century will only increase human pressure on already-scarce resources.
|BC physiography, credit Wikimedia Commons|
|Conceptual design of the proposed BC Hydro Peace River Site C project|
Earlier this week, the Pew Environment Group (PEG) released a landmark report entitled "A Forest of Blue: Canada's Boreal Forest, the World's Waterkeeper." It's no surprise to me that the connections between forests and water resources are finally being explored in detail. I'll post an article soon on some of that research that I've done recently, as well as another article with an overview on the PEG report and its connections to a book that I've been reading (Vanishing Halo: Saving the Boreal Forest). There is hope that the ecological wealth of the boreal forests that still stand in North America and Eurasia will be recognized and preserved for the sake of everyone, not just those who live there. Where the boreal forest band crosses northern British Columbia, and where other forests occur in the southern portions of the province, it is incumbent on the provincial and national governments and the people of Canada, the US, and conservation groups to work together to husband the forest and its resources, including its abundant freshwater, in a responsible manner.
 Hamlet, A., and D. Lettenmaier, 1999: "Columbia River Streamflow Forecasting Based on ENSO and PDO Climate Signals." Journal of Water Resources Planning and Management, v. 125, no. 6, pp. 333 - 341. DOI: 10.1061/(ASCE)0733-9496(1999)125:6(333)
 Hamlet, A.F., and D.P. Lettenmaier, 2000: "Long-range climate forecasting and its use for water management in the Pacific Northwest region of North America." Journal of Hydroinformatics, v. 2, no. 3, pp. 163 - 182.
 Vörösmarty, C.J., P. Green, J. Salisbury, and R.B. Lammers, 2000: "Global Water Resources: Vulnerability from Climate Change and Population Growth." Science, v. 289, no. 5477, pp. 284 - 288. DOI: 10.1126/science.289.5477.284
 Milly, P., J. Betancourt, M. Falkenmark, R. Hirsch, Z. Kundzewicz, D. Lettenmaier, and R. Stouffer, 2008: "Stationarity Is Dead: Whither Water Management?" Science, v. 319, no. 5863, pp. 573 - 574. DOI: 10.1126/science.1151915
 Webb, R.H., and J.L. Betancourt, 1992: "Climatic variability and flood frequency of the Santa Cruz River, Pima County, Arizona." U.S. Geological Survey, Water-Supply Paper no. 2379, 40 pp. Available in djvu.
 Woodhouse, C., S. Gray, and D. Meko, 2006: "Updated streamflow reconstructions for the Upper Colorado River Basin." Water Resources Research, v. 42, no. 5. DOI: 10.1029/2005WR004455
 IPCC, 2007: "Summary for Policymakers." Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller, Eds., Cambridge University Press, Cambridge, UK, and New York, NY, USA, pp. 1 - 18. Available in html and pdf.
 IPCC, 2007: "Summary for Policymakers." Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, pp. 7 - 22. Available in html and pdf.
 Held, I., and B. Soden, 2006: "Robust Responses of the Hydrological Cycle to Global Warming." Journal of Climate, v. 19, no. 21, pp. 5686 - 5699. DOI: 10.1175/JCLI3990.1
 Barnett, T., J. Adam, and D. Lettenmaier, 2005: "Potential impacts of a warming climate on water availability in snow-dominated regions." Nature, v. 438, no. 7066, pp. 303 - 309. DOI: 10.1038/nature04141
 Kundzewicz, Z.W., L.J. Mata, N.W. Arnell, P. Döll, P. Kabat, B. Jiménez, K.A. Miller, T. Oki, Z. Sen, and I.A. Shiklomanov, 2007: "Freshwater resources and their management." Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, pp. 173-210. Available in html and pdf.
 Fischlin, A., G.F. Midgley, J.T. Price, R. Leemans, B. Gopal, C. Turley, M.D.A. Rounsevell, O.P. Dube, J. Tarazona, and A.A. Velichko, 2007: "Ecosystems, their properties, goods, and services." Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, pp. 211-272. Available in html and pdf.