A watershed’s fragile life

The Sunshine Coast Regional District (SCRD) shocked many when they declared a local state of emergency triggered by a severe drought, on Oct. 17, 2022. All non-essential commercial uses for water, such as breweries and cement facilities, were halted until further notice.

Photo by Howard Greenwood

Prior to this, and in anticipation of the upcoming months, Stage 4 water restrictions had been put in place. The limited water supply was prioritized for human health, firefighting, and minimum creek flow requirements. Residents were urged to conserve as much water as possible and were warned about the upcoming months.

The restrictions banned water use for washing vehicles, outdoor watering, construction activities, road and property maintenance, and various recreational purposes.

Abbotsford during the November 2021 floods.

Vancouver Island and the Sunshine Coast have been particularly vulnerable to this water crisis, having a long history of freshwater shortages, droughts, and floods. Forest eco-hydrologist Adam Wei at the University of British Columbia Okanagan campus (OK UBC) argues that to understand the long-term effects of this crisis, one must recognize the impact on watersheds.

“Our whole world is composed of different nestled watersheds. We live in a watershed,” Wei says. He heads UBC’s Cluster of Research Excellence on Watershed Ecosystems which hopes to better the health of forest and watershed systems.

He is particularly interested in the effects that the recent record-breaking summer droughts and floods have had on the communities and watersheds of British Columbia’s Lower Mainland and the
Sunshine Coast.

“We understand that if water is negatively impacted, then many other ecological processes and functions such as water quality and supply, aquatic habitat and biodiversity can be affected as well,” Wei says.

What are watersheds?

A watershed is an area of land where all flowing surface water converges to a single point or flows into another body of water, such as a river or ocean.

Watersheds are natural entities for studying, monitoring, and managing interactions between terrestrial and aquatic processes.

A well-functioning watershed plays a crucial role in constructing budgets of water, sediment, and other nutrients, a network that humans heavily depend on. Many communities count on watersheds for outdoor recreation sites involving the use of lakes, rivers, or streams, but more importantly, for fresh water.

Where has all the water gone?

The residents of the (SCRD) have become accustomed to drought, having experienced Stage 4 drought or higher for many of the past several years. This leaves freshwater systems, irrigation, and community water supply vulnerable. While recent events have brought considerable attention to SCRD’s water situation, many residents claim this problem has been festering for a long time.

The recent crisis began late August of 2021. Approximately two months had passed since significant rainfall, and summer temperatures had reached their peak. The Chapman Creek watershed, one of SCRD’s main reservoirs, was abnormally dry. As a response, those Stage 4 water restrictions were set in place.

Forest fires and droughts go hand in hand

Wei also stresses the importance of making the connection between drought and forest fires.

“We must also recognize that climate-resultant drought events often go with wildfire events, particularly in the B.C interior forests,” he says. “As a result of possibly combined effects of severe climate events with wildfire disturbance, the severity of droughts could be greatly increased.”

As temperatures steadily rise, evaporation of surface water may diminish snow and rainfall. Moreover, drier vegetation increases the likelihood of forest fires.

Adam Wei.

In addition to jeopardized fresh water supply, reduced streamflow in essential creeks directly affects aquatic habitats, and in turn the survival of aquatic organisms. It also means reduced soil quality and potential death of nearby vegetation and trees.

Inversely, floods also have major consequences on watersheds. In general, large floods can do some considerable damage to local watersheds. They can cause major soil erosion and landslides, alter water courses, damage infrastructure and more.

The devastating floods caused by severe rainfall in November 2021 that affected the southern and interior regions wreaked havoc on many communities and water systems’ health.

“As aforementioned, climate can interact with forest disturbance effects, which may lead to worsened flood or drought severities. This is something we need to play more attention to when we predict and manage floods or droughts,” he says.

More research is needed

Wei hopes there will be more research on climate change and its effects on water systems. His team recognizes the significant levels of disturbance, both natural and human causes, that not only impacts B.C’s watersheds but raise critical questions about forest management, long-term sustainability and vulnerable communities. He and his team are optimistic about the future and are actively studying ways to support watersheds and forests in case of crisis.

The long-term goal of his team is to advance watershed ecosystem science, establish a center on watershed ecosystems, and develop watershed governance procedures in accordance with Indigenous values. The team takes an interdisciplinary approach in studying various critical and connected processes at the watershed scale, and to study watershed-ecosystem-based governance.

“My research group is studying various subjects related to forest hydrology, watershed ecosystems and interactions between climate and forest disturbance. I believe the results from these studies can greatly support forest and watershed management strategies for protection of water and watershed ecosystems,” he says.

For more information visit:

eegs.ok.ubc.ca/about/contact/adam-wei