Resource

Bearspaw development. Design and construction of a side-channel overflow spillway

Resource Type
Industry Papers and Articles
Reference Title
Bearspaw development. Design and construction of a side-channel overflow spillway
Author/Presenter
Pildysh, M.
Slopek, R.J.
Nunn, J.O.H.
Keys, R.A.
Organization/Agency
National Research Council of Canada
Canadian Society for Civil Engineering
Publisher Name
Canadian Science Publishing
Year
1990
Date
06/1990
Journal Title
Canadian Journal of Civil Engineering
Journal Volume
17
Journal Issue
3
ISBN/ISSN
ISSN: 0315-1468
Topic Location
Canada
Alberta
Abstract/Additional Information

An emergency spillway with a capacity of 1840 m3/s has been built to increase the spillway capacity of the 30-year-old Bearspaw Development so that it can safely pass the probable maximum flood. A unique aspect of the free-overflow, side-channel emergency spillway is the weir. This consists of an earthfill dyke with a cap and downstream facing of reinforced concrete. Comprehensive hydraulic model testing was undertaken to provide detailed design data and optimize the design of the emergency spillway. The overflow weir substructure is a zoned earthfill dyke with a 2 mm thick polyethylene membrane at the top of the impervious core to prevent frost heave of the concrete lining. The reinforced concrete lining of the spillway is required for erosion protection and is designed to withstand the hydrodynamic drag and uplift forces caused by flowing water as well as piezometric uplift pressures due to seepage. Additional aspects of the subject are discussed.