DOT Type II Turbidity Barrier & Anchor System for Sediment Control During rock-filled coffer dam construction. Enviro Liner® 6060 Geomembrane – Upstream Coffer Dam Lining.
Background Information and Challenge
Parks Canada Trent Severn Waterway Lock 14 Crowe Bay’s dam was constructed in 1913 and, due to its age and the degradation of concrete, required rehabilitation and a bridge replacement. The scope, which included bridge demolition and replacement, required constructing a temporary coffer dam for water diversion and creating a dry workspace.
Solution
To protect the aquatic environment surrounding the construction, the contractor installed a DOT Type II Turbidity Barrier to manage sediment during construction on the upstream and downstream sides of the rock dam. Part of the rock-filled dam’s construction included lining the dam’s upstream face with an Enviro Liner® 6060 geomembrane, which acted as an impermeable barrier to prevent infiltration and erosion of the temporary dam. The geomembrane liner was keyed into the trench at the top, its seams overlapping at 1.5m, and used sandbags and granular for the toe ballast.
Results
Dam was constructed and lined in 1 day. The contractor was very pleased with the outcome and performance of the barrier and lining systems, which were simple to deploy and met expectations.