Emergency inspection following flash flooding at Christina Lake
In the early hours of April 26th this year, three homes were affected by flash flooding at Christina Lake in the Regional District of Kootenay Boundary (RDKB), 20km outside of Grand Forks.
Following the flood, in which all residents were evacuated, Austin Engineering’s Hydrotechnical team was called to perform an emergency inspection at the scene on Fife Road to determine the cause.
Upon inspection, the team found that beavers had built a dam over a weir on the reservoir.
Weirs are common features at lakes and reservoirs designed to control water flow and offset during heavy periods of rain.
Overnight, the beaver dam at Christina Lake broke, causing extensive flooding, resulting in large-scale damage to residential properties and infrastructure.
A portion of Fife Road, including a culvert, was removed by the floodwaters.
Typically, stormwaters are released to channels alongside roads by passing through culverts – pipes built under roads for this purpose.
However, in this instance the magnitude of the floodwaters washed out the culvert and jumped the existing road channel, forming a two-metre deep gully in one Fife Road resident’s yard.
Although engineers could not determine what prompted the beaver dam to break, it is possible that heavy rains and water from the reservoir behind the dam created too much pressure for the structure to withstand.
Hydrotechnical engineers are well-versed in beaver-related issues; Canada’s largest rodent is a common source of blockages and flooding of water sources during the springtime.
As a result, engineers have developed several devices and strategies to mitigate such issues, including beaver boxes, fences, guards, drains and revellers.
Post-emergency inspection, Austin Engineering made several recommendations to the RDKB and FLNRORD (Ministry of Forests, Lands, Natural Resource Operations & Rural Development).
The Hydrotechnical team is now in the process of developing a design to repair the channel alongside Fife Road to offset any overflow from Christina Lake.
Using funding from Emergency Management BC (EMBC), Austin Engineering is able to restore the channel and culvert to their original state.
Austin Engineering continues to work with the RDKB, EMBC and FLNRORD to promote a solution that will ensure the safety and wellbeing of locals, as well as the protection of habitat at Christina Lake.
The Ministry of Transport and Infrastructure (MOTI) has repaired all roads affected by the flood event.
The team at Austin Engineering consists of leading technical experts in hydrotechnical engineering, water, environment, infrastructure, energy and resource management.
Austin Engineering develops conceptual designs for various features that interact with water; including highway culverts, canals, dam spillways and outlet work, as well as related structures for irrigation projects.
Read more about our hydrotechnical work here.
Find out more about the flooding at Christina Lake and on Fife Road in the news: https://globalnews.ca/news/7810496/christina-lake-b-c-flood-strikes/