Using Data to Manage Watershed Risks

Estimated Read Time: 5 Minutes

How can we make better land management decisions?

Climate change is expected to result in considerable changes to streamflow. Effects will differ from year to year and in different types of watersheds. While precipitation is projected to increase in the wet season and decrease in the dry season, on average, the main impacts on streamflow for most watersheds will likely result from changes to snowpack caused by warming.

Pacific Dogwood on shores of Cowichan River, Vancouver Island, British Columbia, Canada.

  • „In general, we can expect larger fall and winter flows, with greater risks of shoreline erosion and changes in sediment patterns.
  • „In winter, there will be increased risk of landslides and debris flows on steep slopes, or ice or debris jams on lower reaches.
  • „In spring, we can expect earlier and lower freshets (spring high flows).
  • In summer, lower base flows and high-water temperature could change the behaviour and success of salmon and other species.

At the same time, Sea Level Rise will back water up into estuaries – sometimes many kilometers up the coastal inlets. Transportation facilities often hug shorelines along coasts and rivers, with no alternative route or space. Some sections of highway may need to be raised to avoid Sea Level Rise or added flood risk.  Additional scour protection at bridges may be necessary. We will need to upgrade and protect our shorelines using environmentally sensitive methods.

Managing Risks to our Watersheds

In 2010, the Cowichan Valley Regional District (CVRD) created an Environmental Initiatives Service which has since identified a number of potential risks to our aquifers and watersheds. Our aquifers and watersheds provide our communities with clean drinking water, beautiful landscaping and gardens, food and wine production, recreation and tourism, fish and wildlife habitat, and economic prosperity – and all linked to our high quality of life. Risks to our watersheds can include both water quality and water quantity challenges, which will likely increase with climate change. Risks could mean added future costs to taxpayers in our region if we do not plan for such events.

Water Quantity
Water Quality

Watershed Planning

Watershed planning is a way of integrating land use planning for our communities with other impacts in our watershed to ensure that all the resources are managed effectively. With the proposed Drinking Water and Watershed Protection Service, CVRD staff will have a clear mandate to support region-wide water and watershed managementWatershed including the implementation of programs. The service would enable the development of specific watershed management plans that would characterize risks to water supply and water quality. Effective watershed planning  would help inform land use planning and growth patterns as well as understanding infrastructure and water utility needs across the region.


If you would like to learn more about the proposed Drinking Water and Watershed Protection Service, please join us at the following public information event TONIGHT to listen to a presentation and ask questions so you can make an informed vote during the Local Government Election Referenda on October 20, 2018 – the proposed service will be a referendum question.

    Tuesday, October 9 from 6:30 pm – 9:00 pm (TONIGHT)
    Mill Bay Community League Hall
    1035 Shawnigan Mill Bay Road, Mill Bay