Flood Warnings and Advisories

Flood Warning – Vancouver Island (West & South)

ISSUED: 10:00 AM February 1, 2020

The River Forecast Centre is upgrading a Flood Warning for:

  • Western Vancouver Island
  • Southern Vancouver Island

The River Forecast Centre is upgrading to a Flood Watch for:

  • Eastern Vancouver Island

    Very heavy rainfall fell over Vancouver Island on Friday due to an atmospheric river. Temperatures increased considerably due to the sub-tropical source of the atmospheric river. The warmer temperatures created a rain-on snow event for many rivers on Vancouver Island.


    A summary of some rivers in Western Vancouver Island and Southern Vancouver Island that are now under Flood Warning include:

    • San Juan River near Port Renfrew (08HA010) peaked above 1300 m3/s at 1AM and was near a 100-yr flow. It is gradually receding.
    • Koksilah River at Cowichan Station (08HA003) reached 371 m3/s at 4am - between 50 and 100-yr flow. It is beginning to recede.
    • Cowichan River near Duncan (08HA011) is near 570 m3/s and nearing its peak. This is between a 20 and 50-yr flow.
    • Chemainus River near Westholme (08HA001) peaked at 3am with a flow above 700 m3/s - near a 50-yr flow. Flows are beginning to recede.
    • Nanaimo River near Cassidy (08HB034) is leveling off around 890 m3/s - near a 10-yr flow.


    A summary of some of the rivers in Eastern Vancouver Island under Flood Watch include:

    • Englishman River near Parksville (08HB002) peaked at 4am at 522m3/s - slightly above a 10-yr flow. Flows are beginning to recede.
    • Little Qualicum River near Qualicum Beach (08HB029) is flowing at 220m3/s which is slightly above a 20 year flow.

    The rainfall has ended and flows are expected to gradually recede through the rest of the weekend. There will a slower recession in rivers with lake sources like the Cowichan River.


    The public is advised to stay clear of the fast-flowing rivers and potentially unstable riverbanks during the high-river-level period.


    The River Forecast Centre will continue to monitor and provide updates as conditions warrant.

    Contact for Media Relations, Ministry of Forests, Lands, Natural Resource Operations and Rural Development:
    Tel: 250 356-7506

    Levels of Warnings/Advisories:

    1. High Streamflow Advisory: River levels are rising or expected to rise rapidly, but that no major flooding is expected. Minor flooding in low-lying areas is possible. This is the lowest level.
    2. Flood Watch: River levels are rising and will approach or may exceed bankfull. Flooding of areas adjacent to affected rivers may occur. This is the intermediate level.
    3. Flood Warning: River levels have exceeded bankfull or will exceed bankfull imminently, and that flooding of areas adjacent to the rivers affected will result. This is the highest level.

    Links:

    1. Home of River Forecast Centre
    2. Current Streamflow Conditions and Flood Forecast Modeling
    3. Map of Current Streamflow Return Periods for All WSC Stations
    4. CLEVER Model 10-day Forecasts of Discharges and Return Periods
    5. COFFEE Model 5-day Forecasts of Discharges and Return Periods
    6. Back to page of Flood Warnings and Advisories