Flood Warnings and Advisories

Flood Watch – Central Vancouver Island including Port Alberni
ISSUED: 1:00 PM February 1, 2020

The River Forecast Centre is issuing a Flood Watch for Central Vancouver Island including:

  • The Ash River, Sproat River and Somass River
  • Port Alberni

An atmospheric river event has causing heavy precipitation for Vancouver Island and about 100mm of total rainfall for Central Vancouver Island on Friday. The Ash River, Sproat River and Somass River have risen rapidly last night and are currently running at flows between the 2 and 5-year return periods.

Based on the latest updated hydrologic modeling, the flows in the Ash River and Sproat River are expected to rise to the 5-year return period flows. The estimated flow for the location of the inactive Water Survey of Canada’s station, the SOMASS RIVER NEAR ALBERNI (08HB017), is expected to peak at about 900 m3/s, which is a flow about the 5-year return period, tonight or tomorrow morning.

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 continues to monitor the situation and provides 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