Tahsis Flood Protection Improvements Project: Phase 3

pre-construction

This application is for phase 3 of a 4-phase project to protect Tahsis’ North Village from riverine and coastal floods up to 1:200 year rainfall levels (accounting for storm, tide and sea level rise effects). An estimated ~$41 million worth of public and private assets and essential infrastructure is currently at risk in the North Village - including our public works yard, water supply well pumping station, salmon hatchery, ambulance station, RCMP station, fire hall, recreation complex/emergency reception centre, daycare, and elementary/secondary school. Via phases 1 and 2 (funded), we are completing or have completed various enhancements to dikes, detention ponds, pump and drainage infrastructure, and the North Maquinna Dr. lock block flood wall along the Tahsis River. In this third phase, we will extend the North Maquinna Dr. lock block flood wall by 520m, and add a 60m earth berm terminating near the river mouth. All phases of work are informed by a comprehensive Flood Risk Assessment (2019). We are working closely with our local First Nation and collaborating with regional partners. This project’s focus on structural assets is being complemented by other work to control future development in the floodplain (including via a newly-adopted floodplain management bylaw), and by efforts to relocate essential infrastructure - where feasible - out of the floodplain entirely (including our sewage treatment system and fire hall). This project includes: -140m long flood wall at an approximate height of 0.75m (1 Lock Block in height). -380m long flood wall at an approximate height of 1.50m (2 Lock Blocks in height). -60m long earth berm at an approximate maximum height of 2.5m. -Internal drainage improvements (catch basins, leads, and flap gates) along the flood wall and berm. -Various riprap bank stabilization along the riverbank to accommodate the wall and berm loads. -Environmental offsetting measures (to replace disturbed fish habitat at a ratio of 2:1)