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The City of Revelstoke, located on
the Columbia River and the Trans Canada Highway, was incorporated as a
city in 1899. The City's main industries are the CP Rail railroad,
forestry and tourism, including helicopter skiing and snowmobiling. The
water utility has about 2,700 service connections serving 7,350 people.
The City has used Greeley Creek since around the turn of the century as
a principal water source. The watershed, located east of the City, is
some 47.6 km2 in area and varies in elevation from 670 m to 2500 m. The
watershed is first growth trees, and because of the terrain, no public
access. The watershed is in a region of North America with the highest
snowfall depths that can exceed 20 m per year. The City has a water
license to withdraw up to 18.2 ML/d of water.
The water supply system
consisted of a diversion structure, an earth lined settling basin, an
intake complete with a coarse trash rack and gravity water supply
through an approximately 10.5 km of 300 mm to 450 mm diameter
transmission pipe. There are two connections points off the transmission
main including a 3.78 ML steel reservoir adjacent to the Trans Canada
Highway. Up to August 28, 1995 this source had not been treated.
In August 1995 the City
experienced a waterborne disease outbreak. After extensive public
consultation and project planning the City decided to construct a water
treatment plant employing micro membrane filtration and chlorine
disinfection. The funding approvals were not confirmed until June 1999.
Given the heavy snowfall in the area the building envelope and all
outside work would need to be completed by November to avoid the added
cost and difficulty of winter construction. This was not possible by the
conventional design/tender approach. To meet the plant start up target
of May 2000 the City adopted a fast track construction management
approach to the project design and construction. |
