Bowker Creek is an urban waterway in the capital region, stretching 3.4 km above ground and 4.5 km underground through pipes in Saanich, Victoria, and Oak Bay. It begins at the University of Victoria, and flows west and then south through Saanich in the Shelbourne Valley, and southeast through Victoria and Oak Bay to the outlet in Oak Bay. There is also a significant tributary that runs through Cedar Hill Golf Course.
In the past, Bowker Creek was a natural, winding stream with small tributaries and wetlands. It was home to fish like cutthroat trout and salmon, and local First Nations people relied on it for food and water. However, as the area developed, much of the creek was buried in pipes, and its natural landscape was changed.
Today, Bowker Creek is highly urbanized and surrounded by buildings and roads, which has led to problems like flooding and poor water quality. About 45% of the watershed is covered by hard impervious surfaces, like roads and roofs, which prevent rainwater from soaking into the ground and instead direct polluted water into the creek. This has made the creek prone to flooding and has harmed the aquatic habitat.
Despite these issues, people still visit and enjoy areas around Bowker Creek, such as Cedar Hill Park, the UVic campus, Browning Park, Oak Bay High School and Bowker Creek Park.
A watershed is the area of land that drains surface water and groundwater to a common water body, such as a creek, stream, lake or the ocean. We all live in a watershed, regardless of how far we are from a body of water. Learn more
Biodiversity in the Watershed
Although development has severely impacted habitat in the Bowker Creek watershed, there remains areas with native plants and wildlife. Learn about the ecosystems in the watershed and their characteristics:
The Bowker Creek watershed is found in the Coastal Douglas-fir Biogeoclimatic zone, characterized by mild winters and dry, warm summers.
Garry oak meadows, which were once common around Victoria and nearby areas, are now rare and found mainly in small pockets among urban and agricultural land. These meadows are home to many rare and endangered species. One example in the Bowker Creek watershed is on Mt. Tolmie’s northern slopes.
The watershed also faces challenges from invasive plant species like Scotch broom, Himalayan blackberry, golden willow and English ivy. The remaining native plants offer important food and shelter for wildlife. Efforts to create more naturalized green spaces along Bowker Creek aim to enhance wildlife habitat by removing invasive plants and reintroducing native species.
Bowker Creek’s freshwater ecosystems mostly support small invertebrates like insect larvae and worms, with only a few fish near its mouth. While the water quality is generally acceptable, the condition of the creek channel limits fish habitat. The underground storm drains are not suitable for life because they lack sunlight for plant and algae growth.
The open sections of the creek are exposed to sunlight but are too straight and deep for plants and fish to thrive. Natural streams have features like rocks and bends that slow the water and create shelters. In Bowker Creek, rainwater from hard surfaces flows quickly, causing flooding and erosion, making it hard for fish to live there.
Future restoration efforts aim to reduce hard surfaces, allow more rainwater to soak into the ground, and add natural features to the stream. In 2020, the Friends of Bowker Creek started a program to bring chum salmon back to the creek’s lower reaches.
Riparian ecosystems, which are the areas between land and water, are also important. They support specialized plants and microbes, help manage floodwaters, and filter out pollutants. However, few natural riparian zones remain along Bowker Creek due to changes made to the stream for drainage. Some small riparian areas still exist at the University of Victoria and Cedar Hill Golf Course.
Bowker Creek flows into Oak Bay, a rich marine environment. The quality of the creek’s water affects the bay, which has rocky shorelines, sandy beaches, and a variety of wildlife including seabirds, shorebirds, and harbour seals. The estuary is part of the Victoria Harbour Migratory Bird Sanctuary where many seabird stop to rest and feed. Strong tides and cold water from the Juan de Fuca Strait bring nutrients to the bay, supporting kelp beds and fish, and orcas are occasionally spotted in the deeper waters.
In 2020, Friends of Bowker Creek started the community science initiative, the Chum Salmon Recovery Project to restore Chum salmon to the lower reaches of Bowker Creek. Learn more here.
Threats in the Watershed
Climate change is expected to result in will result in changes in our area's precipitation and temperature patterns, as well as more frequent storms and increased likelihood of floods, fires and sea level rise. Local species may not easily adapt to the new climate conditions.
With greater impervious area (roads, houses, etc.) and higher intensity rainfall events, stormwater runoff can flash flood streams, negatively impact fish spawning habitat through erosion and sediment deposition, prevent groundwater recharge and impact water quality.
Non-native species that aggressively compete with native plants and animals can drastically alter the landscape.
The Bowker Creek watershed, as with many areas in BC, is facing immense development pressure. With municipalities now required to meet new provincial housing targets, the watershed could continue to lose pervious area, critical tree canopy, green spaces, and connectivity with dramatic impacts on biodiversity, human health and culture.
Chemical and sewage pollution can be directly toxic to many plants and animals, and can modify the oxygen and nutrient content of the air and water. Emerging toxins such as the tire wear toxin 6PPD-Quinone will impact local salmon populations. Emerging toxins, such as the tire wear toxin, 6PPD-Quinone, has been shown to have lethal effects on coho salmon.
Help Protect the Watershed - what can we do?
There are many ways you can get involved and learn how to protect and enhance Bowker Creek watershed. Because the watershed is urban it is covered in impermeable surfaces such as parking lots, buildings, and roads. Rainwater flows quickly across these surfaces, picking up debris and pollution, and draining into storm drains that then lead directly to Bowker Creek. You can help by limiting the introduction of pollutants (oils, gas, pesticides, fertilizer, chemicals, etc.) as well as allowing rainwater to soak into the ground and by gardening with native plants and removing invasives.
The CRD conducts its business within the Territories of many First Nations, all of whom have a long-standing relationship with the land and waters from time immemorial that continues to this day. Statement of Reconciliation
