Greenwood Flood Protection

Greenwood, BC

Project Details

Prime Consultant

City of Greenwood

2019

2020

Disciplines

British Columbia | Environment | Environmental Infrastructure | Erosion Control | Flood Mitigation | Flood Protection | Geomatics | GIS | Hydrogeology | Hydrotechnical | River Hydraulics | Sustainable Design | Water

Project Profile

 

ISL partnered with the City of Greenwood and prepared a grant application through the Community Emergency Preparedness Fund in 2019. The application was successful and the City was awarded $150,000 to fund a flood mapping, flood planning and flood risk assessment study. The study relied heavily on GIS mapping, hydrotechnical engineering and hydrology.

Bathymetric channel surveys throughout Boundary Creek were completed and combined with LIDAR data provided by GeoBC. This data set informs the digital model which will house the 200 year flood event and detail the flood conditions present during each modeled scenario. Results from this model informed the mitigation strategies best suited to protect the residents and business owners of Greenwood from future flood events.

In recent years, Greenwood has experienced both overland flooding from Boundary Creek, as well as groundwater flooding due to a rise in the groundwater table during high creek flow conditions.

To address this condition, ISL included a groundwater study into the project scope. Seven piezometers were installed throughout Greenwood, equipped with pressure and temperature transducers which collected real time data to inform the study. The locations for these transducers were selected to provide a groundwater cross section through the flood plain, perpendicular to Boundary Creek, as well as parallel to Boundary Creek. Transducers were also installed on the Louisa St. bridge and on the Deadwood St. bridge to accurately compare creek flows to groundwater conditions.