Rivers Day is an annual celebration of the world's waterways-the arteries of our planet-with people around the globe taking part in local events such as paddle tours, nature walks, tree plantings, river cleanups and community festivals. People enjoy these activities in part to raise awareness and improve stewardship of rivers, and their participation also celebrates their cultural, social, economic and ecological importance.
While celebrating the beauty and bounty of rivers, it is worth reflecting on a crucial point: that what happens in rivers reflects what happens on land. The two are intertwined in "watersheds," a word used to describe and area of land draining into a common river, lake or sea. One quarter of British Columbia is in the Fraser River watershed; in the Fraser Valley we are in the heart of this system.
Our home watershed has provided us with a bounty of wealth, since time immemorial for the Sto:lo people and now also for the many diverse people who call this region home. However, as land use intensifies in the Fraser Valley watershed, small and large watercourses weave through urban, industrial and agricultural lands that can easily pollute water and affect human health. Human activities also impact streams and groundwater aquifers, on which we rely for drinking water, crop irrigation, industry, recreation, and the provision of natural spaces for humans, fish, and wildlife. Our challenge is to efficiently use the land, while protecting water from harm.
Fortunately, our understanding of watersheds has improved dramatically in recent decades, as well as our ability to mitigate the impacts of urbanization, forestry and agriculture. One key method is to establish strips of native shrubs and trees along streams, lakes, wetlands and other water bodies. The filtering effect of these vegetated buffers prevents waterways from becoming clogged with silt, thereby enhancing flow, drainage and flood protection. Buffers also filter out "nutrients" from animal waste, which together with silt and sunlight provide ideal conditions for the growth of invasive plants such as reed canary grass and blackberry. Where these invasive plants grow they require regular and costly removal to maintain flows. Shade cast by shrubs and trees also keeps sun-loving invasive plants at bay, while keeping water cool enough for salmon.
In addition to protecting water, these vegetated buffers produce a number of benefits vital to human health and welfare, commonly called "ecological services." These services generate wealth in the form of fertile agricultural lands, world-class water purification, clean air and flood protection.
Fraser Valley soils typically contain fine particles of silt deposited by the Fraser River. These fertile but delicate soils are highly prone to erosion, especially during heavy winter rains. The roots of native vegetation along waterways act to hold the soil, while grasses, shrubs and trees filters out the soils and pollutants washed off forests, fields and urban areas.
As our knowledge of watersheds grows, it has become apparent that vegetation plays an important role in flood protection. Shrubs and trees can suck up large amounts of water; for example, a cedar forest can take up 60 per cent of the moisture in the soil. Good capacity for water uptake can help keep farmland dry, especially during the Fraser River freshet in May and June.
Another concern we hear from farmers in the Fraser Valley is the loss of pollinators for flowering crops such as blueberries and raspberries. Research shows that native pollinators like bumblebees are crucial to high crop yields, so including native flowering plants can increase berry production.
Other benefits to the valley are their services as air purifiers. Vegetated strips catch windborne dust and pollutants, and protecting against cold winter winds that damage crops and pasture. They also absorb carbon dioxide from the air. Last but not least, vegetated buffers along watercourses, lakes and wetlands provides critical habitat for fish and wildlife, and creates green corridors along which animals can move around the landscape.
The bottom line is that protecting our rivers means understanding the entire watershed and all human activities that occur there. It also means protecting and restoring vegetated buffers along watercourses and wetlands, in order to provide the many ecosystem services that support our communities. It means working together to promote stewardship and sustainability at a local level.
Because many of the services provided by vegetated waterways are a direct benefit to society, one local group, the Fraser Valley Watersheds Coalition, has been working to rebuild vegetated buffers along watercourses and to develop a financial incentive program for landowners who establish vegetated buffers. Incentives would ensure that having vegetated buffers is good business as well as good stewardship.
Many local organizations like the Fraser Valley Watersheds Coalition, Chilliwack/Vedder River Clean Up Society, the Fraser Valley Conservancy, the Abbotsford Soil Conservation Association, the WaterWealth Project, the Cultus Lake Association, Miami River Streamkeepers and many more have been getting their boots on the ground working to revitalize our home waterways. On Rivers Day, Sept. 29, there are a wide variety of activities to celebrate our local waters throughout the Fraser Valley and everyone is welcome.. Sheila Muxlow is the campaign director with the WaterWealth Project. Detmar Schwichtenberg is the president of the Fraser Valley Watershed Coalition.
© Copyright 2013