Water Stewardship Information Sources

Citation BC Hydro. 2011. Ash River watershed: Watershed Plan, Final Draft. BC Hydro.
Organization BC Hydro
URL http://fwcp.ca/app/uploads/2015/07/ash_watershed_plan.pdf
Abstract/Description or Keywords The Ash River watershed is situated about 40 km northwest of Port Alberni in central Vancouver
Island, between the Beaufort Range and Strathcona Provincial Park. The upper Ash watershed is
dominated by mountains up to 2000 m, which form the boundary between the Ash, Campbell and
Puntledge watersheds, and small areas of permanent snowpack exist there. From
Oshinow Lake at elevation 410 m, the Ash River drops a further 80 m in 13 km to Elsie Lake
Reservoir. The lower parts of the watershed have lower relief than the upper basin. Below Elsie
Lake Reservoir the lower Ash River flows into the Stamp River and from there into the Somass
River before meeting the ocean at Port Alberni. There are three lakes on the Ash River mainstem,
Oshinow, Elsie and Dickson Lakes, and several smaller lakes on tributaries.
The Ash River basin is in the transition zone between the wet west coast and drier east coast
climates of Vancouver Island. The basin is affected by frontal storms arriving from the southwest off
the Pacific Ocean with strong, moist winds that bring heavy precipitation for durations of a few
hours to a few days. Monthly rainfall can be as high as 800-900 mm between November and
March. Peak inflow, however, occurs from May to July from snow melt, whereas August and
September are low flow months.
The Ash River watershed is in the traditional territories of the Hupcasath First Nation and Tseshaht
First Nation.
The Ash River project, completed in 1958 by the B.C. Power Commission, consists of Elsie Dam at
the outlet of Elsie Lake Reservoir and four saddle dams. Water is diverted from Elsie Lake
Reservoir through a 7.8 km tunnel and penstock to a powerhouse on the shoreline of Great Central
Lake (Figure 2). The plant usually operates at maximum capacity (10.7 m
3
/s), except in late
summer when inflows are low and during a 1-2 week annual maintenance period, usually
scheduled for August. Flows are released down the Ash River from Elsie Dam to support fish and
other objectives, according to operations described in the Ash River Project Water Use Plan (BC
Hydro 2004). Updated minimum flows agreed to in the WUP are 3.5 m3
/s from May 1 to October
31; 5 m3
/s from November 1 to April 30; and two separate pulse flows for adult steelhead migration,
of 10 m3
/s for two days between August 1 and September 30.
Information Type report
Regional Watershed Vancouver Island North
Sub-watershed if known Ash River
Aquifer #
Comments
Project status complete
Contact Name
Contact Email