Wascana Lake Retaining Wall

Wascana Lake was created in 1931 as a make work project and is the focal point of the Legislative Grounds. The Wascana Centre Authority concluded in 1997 that much of the erosion control embankment at Wascana Lake had deteriorated sufficiently and had to be replaced, at least partially, so that the erosion protection could be maintained into the future. The Authority undertook to rebuild some of the North shoreline as a pilot project.

The replacement of the existing materials (boulders set in a concrete) was estimated and while these materials were within the budget of the Authority, the cost to provide a dry working environment (coffer dams) was very expensive. An alternate proposal using precast concrete components was found to have a lower cost. A scheme was developed to provide an economical and more attractive retaining wall with the possibility of regaining more usable shore line.

The key to this scheme was to drain the lake in the fall to expose 10 to 15 metres the relatively flat lake bed near the shoreline. Once the ground was frozen solid, construction equipment could work on the lake bed freely. The retaining wall alignment, some straight and some curved sections was surveyed.

Square precast concrete piles were set in augured holes at approximately 2.6 m c/c and backfilled to the correct top elevation. Inverted 'L' shaped precast panels were manufactured to span from pile to pile and retain the backfill to prevent further erosion. The panels were all the same basic shape with the horizontal joint at the top angled to follow the curves of the shoreline.

The initial wall construction began in February and was completed by March 1998. The first contract included 98 piles and 87 panels for a total wall length of 231 m.

Following Regina's successful bid for the 2005 Canada Games, the Authority decided to extend the retaining wall West to Albert Street, then South, past the weir which controls the lake level and then East along the South shore to an area in front of the Legislature.

The 2004 retaining wall extension included 165 panels (490 m in length) with 8 deck slabs for a pedestrian bridge over the control weir. This was constructed in February and March, 2004. The remaining site work will be done in time for the Canada Games in the summer of 2005.

Owner: Wascana Centre Authority
Architect: Wascana Centre Authority
Structural Engineer: Donovan Engineering
Contractors: Wascana Centre Authority (1998)
Contractors: Dominion Construction (2005)
Precast Supplier: Con-Force Structures Ltd.

 
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