The 1000 Rain Gardens Project in Bowker Creek’s Valley
What is a Rain Garden?
A rain garden is any landscaping that absorbs and filters stormwater (rainwater) runoff from a nearby impervious surface such as a roof, driveway, parking lot or street. The rain garden captures water that would otherwise go down a storm drain and be piped directly into the nearest convenient creek or shoreline.
Rain gardens prevent toxic pollutants such as tire dust, brake dust and cigarette butts from entering our creeks and oceans. They also replenish the groundwater (natural underground water supply) that seeps gradually into creeks and keeps them flowing clean and cool even during summer dry spells. Rain gardens mimic nature’s own “timed-release” system for maintaining healthy water levels for salmon (not too much, not too little).
A rain garden can receive rainwater from a roof downspout directed away from a house, or rainwater from a curb cut on the street. Rich organic soil can absorb rainwater and provide microbes to break down pollutants and a place for plants and trees to grow. Rocks may be placed to control erosion of soil. Overflow drains allow the rain garden to retain and slowly release rainwater accumulated during rainstorm events. Paving can be graded to direct rainwater towards a raingarden and permeable paving will allow rainwater to enter the soil.
Why Rain Gardens?
Stormwater (rainwater) runoff is one of the most devastating problems for all urban and suburban creeks. Bowker Creek is no exception. Whenever it rains, a flash flood of stormwater runoff enters the creek via catch basins and culverts (engineering terms for drains and pipes) — carrying with it tailpipe toxins, brake and tire dust, road salt, excess fertilizers and pesticides, cigarette butts, plastic and paper litter, and whatever else can be swept along by flowing water. This toxic brew sweeps through Bowker Creek into the Salish Sea. The pollutants in stormwater harm fish health, the sediments suffocate spawning gravels where delicate salmon eggs and hatchlings grow, and the sheer volume of water can wash away fish eggs, erode stream banks and destabilize the stream-side trees that provide critical shade for salmon. Groundwater levels fall, because the rain or snow that would normally replenish groundwater has been quickly piped away to the ocean. With insufficient groundwater supplies to last through summer, creek water levels fall dangerously low and water temperatures become dangerously high, threatening fish survival.What’s the Solution?
Get more rainwater infiltrating into the ground, as nature intended, so as to restore a steady seepage of cool, soil-filtered water into the creek. One way to accomplish this is to create “rain gardens” – landscaping that absorbs rainwater runoff from hard surfaces such as roofs, driveways, parking lots and streets. While the environmental benefit of a single rain garden is negligible, the combined benefits of many such gardens can improve the chances for salmon recovery in Bowker Creek. Here are some images of rain gardens in the Bowker Creek watershed and around the Capital Region.UVic Sustainability Scholar Report on Raingardens
UVic Sustainability Scholar Ludwig Paul Cabling delivered a report in 2025 on how the Friends of Bowker Creek Society is leading the 1000 Rain Gardens Project to increase awareness of rain gardens as a tool to reduce excess stormwater flows and pollutants into the BowkerCreekWatershed. See the report here.
Learn and Explore More
Click on the points on the illustration below to learn more about rain gardens, rainwater collection, stormwater management, and how you can help protect Bowker Creek from home.
Non-Permeable Surfaces
Urban development has resulted in an increase of non-permeable surfaces such as concrete, asphalt, stone, brick, and roofing. During periods of heavy rainfall, these surfaces generate large amounts of stormwater runoff, which can lead to storm surges, flash flooding, and stream bank erosion.
Non-Permeable Surfaces
Urban development has resulted in an increase of non-permeable surfaces such as concrete, asphalt, stone, brick, and roofing. During periods of heavy rainfall, these surfaces generate large amounts of stormwater runoff, which can lead to storm surges, flash flooding, and stream bank erosion.
Redirect Stormwater Runoff into a Rain Garden
By installing a rain garden, you can redirect stormwater runoff into a planting bed that acts as a sponge and natural filter, allowing it to infiltrate slowly into the surrounding soil as nature intended and restoring a steady seepage of cool, clean water to the creek.
Harvesting Rainwater
Rainwater can also be collected and stored in dedicated rain barrels, and redistributed to reduce water usage during periods of drought and municipal water restrictions.
Redistributing Rainwater
Watering your garden (and indoor plants) with harvested rainwater has many benefits. Rainwater contains nitrates, an essential macro-nutrient for plant growth. Rainwater also helps keep soil pH levels naturally balanced, and encourages the release of beneficial micro-nutrients from soil.
Deep Root Systems
Native plant species have dense, deep root systems which help break up soil and encourage water absorption.
Native Plant Species
It’s important to plant a variety of species that are able to tolerate both wet and dry conditions, as rain gardens will experience both flooding and droughts.
Berms
A stone or soil berm helps to retain rainwater on the downhill side of the natural slope where your rain garden should be installed.
Groundwater
When rain that would normally replenish groundwater is diverted directly to the ocean, groundwater levels quickly become depleted. As a result, creek water levels fall dangerously low and water temperatures rise too high, which directly threatens fish survival.
Polluted Stormwater Runoff
Rainwater flows off non-permeable surfaces and collects pollutants (grease, oil, and heavy metals from vehicles; fertilizers, pesticides, and household chemicals; litter and debris; construction sediment, etc). This contaminated water then pours into storm drains that empty directly into Bowker Creek.
What you can do…
Rainwater is a natural asset. You can help restore the urban watershed by allowing rainwater slowly seep into the ground, rather than going directly into storm drains and the creek.
The City of Victoria offers a Rainwater Rewards Program for property owners that are developing or making improvements to their property.
The District of Saanich is working on a Natural Asset Management plan that includes stormwater management. Please Consider supporting the plan as it is being developed.