Background Information and Challenge
When Paramount first wanted to put a Freshwater Pond in Greenview, Alberta, they encountered a few groundwater issues. To mitigate these issues, the Owner and Engineer designed the pond to have a subdrain drainage layer (Double-Sided Geocomposite) between the excavated ground and the Reservoir Liner.
The goal of having the subdrain layer down first was to aid the subdrain system with groundwater mitigation and, as a bonus, provide protective underlay to the reservoir liner. Another challenge was when the groundwater was observed coming in at higher elevations up the slopes of the reservoir.
Layfield was chosen for the supply of Enviro Liner® 6160 and the installation. The new design included excavating finger drains up to the problematic areas to help direct more water toward the subdrain system along the floor and eventually move it toward the subdrain sump area. Prior to mobilizing site crews, Layfield’s Project Manager completed a site visit. They identified some areas of concern around the subgrade caused by groundwater seepage along the slopes, which may lead to eventual failures underneath the liner system.
After the Owner and Engineer reviewed the situation further, it was determined that more finger drain installations were needed throughout the problematic areas.
Layfield completed the Geocomposite Subdrain Layer and the Enviro Liner® 6160 Reservoir Liner system. The pond was scheduled to go into service on time.