Aishihik Lake NAM-27

Riparian Nation(s) Canada
Surface Area 146 km2 Mean Depth 30 m Volume 4.38 km3
Shoreline 153 km Catchment Area 2765 km2 Residence Time 14.6 yr
Frozen Period Oct-Jun Mixing Type Dimictic Morphogenesis/Dam
Related Info/Site

Description

Aishihik Lake is named in the Southern Tutchone Indian language meaning for "under the tail", referring to the shape of the bay at the north end of the lake adjacent to the abandoned Aishihik Village. The lake lies within the Ruby Range Ecoregion which is part of the Boreal Corderilla Ecozone of the Yukon Territory. At an elevation of 914 meters above sea level, the lake is bordered to the west by the Ruby Range and to the east by undulating terrain reaching some 1,500 m. Aishihik Lake drains southwestward to the Pacific Ocean via Canyon Lake and the Aishihik, Dezadeash and Alsek Rivers.

The geology of this ecoregion typically includes granodiorite, quartz diorite and granite. The presence of glacio-fluvial and morainal materials in valleys and along mountain flanks provides evidence of glaciation which originated from the Coast and St. Elias Mountains.

Aishihik Lake lies in an area of discontinuous permafrost, the presence and exposure of which lead to significant siltation in the northern end of Aishihik Lake when the lake level was artificially raised after the construction of a dam at the lake outlet in the mid-1970's. The degree of permafrost laden soils sloughing into the lake apparently has decreased as the shoreline has begun to stabilize. Significant shore erosion took place during early stage of the reservoir's life, but data do not exist to state if such conditions have continued.

At elevations below treeline (1200 m a. s. l.), white spruce forests predominate with black spruce occurring in the poorer drained areas. Deciduous trees, though not as abundant, include aspen, balsam poplar and paper birch. Frequently, forests and stream banks are interspersed with sedge meadows. Shrub birch and willows are predominant in the subalpine regions.

Historically, Aishihik Lake was a major gathering place and settlement area for the Southern Tutchone people whose subsistence needs were in part fulfilled through fishing the resources of Aishihik Lake. The principal settlement, Aishihik Village, was located at the north end of the lake.

During the construction of the Alaska Highway (during WW II), an airport was maintained at Aishihik, near the village. Many of the Indian residents died as a result of disease outbreaks (influenza, measles, pneumonia).

Although the inhabitants of the Aishihik Lake area had moved by the mid 1960's to be closer to medical and educational support in Haines Junction, the area still provides an important food fishery to the members of the Champagne/Aishihik Band (located in Haines Junction). Resource use will likely increase in future years as the interest of Indian people in maintaining traditional lifestyles continues to rise. As well, improved access resulting from the construction of a flow control dam in the mid 1970's at the outlet of Aishihik Lake, continues to enhance the recreational fishing opportunities at Aishihik Lake.

The Aishihik River Power Development Project commenced in 1972 and involved the construction of flow control dams at the outlet of Aishihik and Canyon Lakes, a power canal from the outlet of Canyon Lake and an underground power generating station (30 megawatts). During the power project construction period, numerous studies were conducted on lake limnology and stream characteristics by the Federal Department of Environment-Fisheries and Marine Service to attempt to document pre-impact baseline information. Most of the limnological information in this summary originates from these studies (Q).

Photo of Aishihik Lake
Photo: S. Jhonston