Flood Warnings and Advisories

ENDED: High Streamflow Advisory - Somass River
ISSUED: November 29, 2017 11:30 AM

The River Forecast Centre is ending the High Streamflow Advisory for:

  • Somass River including Sproat River, Ash River and tributaries

The water levels of the Somass River and tributaries are dropping slowly and currently below the levels of concern. The Somass River is estimated to be flowing at about 520 m3/s, which is a flow below the 2-year return period flow. Environment and Climate Change Canada (ECCC) forecasts about 30 mm of precipitation for today. However with cooler temperatures, part of this precipitation is expected to fall as snow at higher elevations. Current hydrologic modeling indicates that the flow in the Somass River remain stable or drop slowly through the week, with possibility of small rises.

The River Forecast Centre will continue to monitor conditions and update this advisory as conditions warrant.

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.


  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