Watershed Wanderings
By Julia Jovanovic
Julia Jovanovic is a summer intern with the Lake Windermere Ambassadors. Email her at [email protected]
As drought threatens the wetlands in the Columbia Valley, a new tool must be used to retain the water during hot summers and dry weather in order to preserve the diverse ecosystems offered by these wetlands. Two new possible solutions to this issue have been identified; one solution is maintaining abandoned beaver dams whilst creating habitat that encourages their populations to grow, and the other solution is the use of man-made beaver-like structures.
Historically, beavers have been seen as a type of pest that creates stream damming and flooding which led to their dwindling populations after the over-hunting issue, however, these critters play a vital role in water management, especially in areas where drought puts pressure on water levels, such as in the Columbia Valley watershed.
This is accomplished through the impoundment from the dam causing water to be retained within the structure, stored on the surface, and absorbed into the land, creating larger water capacities and streamflow. In turn, this increased water volume stored and released during drought periods makes ecosystems less vulnerable during intensively dry periods. During floods, water pours over the dam and gets trapped behind its walls. The landscape then is able to hold the water, rather than letting it drain away and travel downstream, contributing to flood control and allowing for the excess water to be released in more dry periods. As a result, beaver dams help increase open water areas for wildlife.
By restoring habitat to allow beavers to build dams as well as maintaining existing abandoned dams, the effects of climate change can be combated in water-stressed regions while maintaining the biodiversity in the area. Luckily, in the Columbia Lake area, these efforts are already in progress and hopefully continue to grow to ensure the ecological and water regulation benefits are upheld.
For areas in which a beaver dam may not be suitable, such as high traffic areas or residential neighbourhoods, beaver dam analogues (BDAs) are a good alternative to simulate beaver dams to help with water retention and biodiversity instead. These man-made structures mimic the shape and function of a beaver dam at a low cost and are effective for areas where beavers are considered less desirable while providing similar benefits as a natural beaver dam. Such features are seen to be currently in the process of being installed throughout the Columbia River and wetlands in the area.
Together, natural and man-made solutions offer a hopeful path forward for protecting the Columbia Valley’s watershed and the many species that rely on them.
A beaver dam is a popular sight on many rivers and creeks.
PHOTO ENVIRONMENT FOR THE AMERICAS
