Flood Warnings and Advisories

High Streamflow Advisory –South Coast and Vancouver Island

ISSUED: 3:15 PM January 31, 2020

The River Forecast Centre is maintaining a High Streamflow Advisory for:

  • South Coast including the Sunshine Coast, Howe Sound and Fraser Valley
  • West Vancouver Island including rivers and tributaries around Tofino, Ucluelet, Bamfield and Port Renfrew
  • North Vancouver Island including rivers and tributaries around Quatsino Sound, Zeballos, Tahsis, and Gold River
  • Central Vancouver Island including the Sproat and Somass Rivers and tributaries around Port Alberni
  • South Vancouver Island including the Cowichan River

An atmospheric river is causing heavy precipitation along the coast of BC today. The heaviest rainfall is currently being measured on the west coast of Vancouver Island and along the North Shore Mountains. Storm total rainfall amounts in the wettest areas may exceed 150-200 mm, with lower elevation and more protected areas expecting amounts in the 50-100 mm range. The source of the atmospheric river is from the sub-tropics, and in addition to precipitation, temperatures are expected to warm, with freezing levels pushing above 2000 m by late-Friday.


Rivers are expected rise through Friday and into Saturday in response to this rainfall.


While rainfall amounts are forecast to be lower in inland areas of Vancouver Island, persistent wet weather over the past few weeks has led to high lake levels on Cowichan Lake and Sproat Lake; outflow from these lakes is expected to exceed levels that have been experienced so far this season, and high streamflow is expected downstream in the Sproat and Somass Rivers and 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