ST. MARY DAM SPILLWAY REPLACEMENT PROJECT GROUT CURTAIN NO. 2 & GROUT CURTAIN NO. 3
ACT was awarded 3 separate contracts to install grout curtains at the St. Mary's Dam in Lethbridge, Alberta. ACT was the Prime Contractor for one of the contracts and a Prequalified Grouting Subcontractor for two of these contracts. We have constructed a total of 3,000 lineal feet of 3 row grout curtain for these contracts.
The St. Mary's Dam is a major water control structure situated in Southern Alberta. It supplies water through an intricate series of irrigation canals for agricultural purposes. The dam is built on Native Lands and two of the contracts incorporated Native Labour initiatives.
The work completed included: overburden drilling, temporary overburden casing installation, rock drilling, exploratory diamond core drilling prior to and upon completion of grouting, extensive water testing, blanket (consolidation) grouting of the upper rock mass, and pressure grouting. In addition to the grouting, we have also installed, grouted and stressed rock anchors in combination with the application of steel fibre reinforced wet shotcrete at the project. The rock anchors and shotcrete were required to stabilize excavated rock surfaces for construction of the downstream flip bucket.
Portions of the production grouting were completed in winter conditions with temperatures as low as -40° C (–40° F). Real time computer monitoring using electronic flowmeters and pressure transmitters linked to a xy-recorder and personal computer to analyze and store data during water testing and grouting.