Flood Warnings and Advisories - River Forecast Centre - Province of British Columbia

Flood Warnings and Advisories

Flood Watch – Central Interior (UPGRADED)
High Streamflow Advisory – Peace (NEW) - BC Interior (MAINTAINED)
ISSUED: 11:45 PM April 27, 2018

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

  • Central Interior including the Nazko River, West Road River, Bonaparte River, and tributary rivers around Cache Creek, Merritt, Williams Lake, Quesnel and surrounding areas

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

  • Peace Region

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

  • South Interior
  • Boundary
  • Kootenay

A ridge of high pressure has brought seasonally hot temperatures across the Britich Columbia Interior. This has led to rapid melt of snow pack at mid-elevation (900-1500m) and the onset of the snow melt season at upper elevations. Snow melt rates observed at automated snow weather stations have grown to 10-25 mm/day at mid-elevation sites, and 0-10mm/day at upper elevations.
Friday is forecast to be the final day of significantly hot weather, and temperatures are expected to ease to closer to seasonal levels over the weekend. A low pressure system is expected to move across Washington and Oregon over the weekend, and this may bring showers across southern BC on Saturday and Sunday.
High streamflow is being observed in many river systems fed by low-to-mid elevation terrain.
These areas include:

  • Okanagan - including tributaries in the Oliver, Osoyoos, Summerland, Penticton, Kelowna, Vernon and surrounding areas
  • Similkameen - including the Tulameen and tributaries
  • Boundary - including the West Kettle River, Kettle River, Granby River and surrounding tributaries
  • Kootenay - including the Moyie River and mid-elevation tributaries in the Castlegar, Trail, Salmo, Creston, Cranbrook and surrounding areas
  • Peace – including tributary rivers draining plateau areas around Fort St. John, Dawson Creek and surrounding areas

In the Central Interior (Cariboo), very high flows are being observed or forecasted at gauged river locations. At the West Road River near Cinema (Water Survey of Canada gauge 08KG001), flows are estimated to be in the 280-300 m3/s range (10-year flow) and rising. On the Bonaparte River below Cache Creek (WSC 08LF002), flows are at 28 m3/s (2-year flow) and rising. Current hydrologic modelling is indicating the potential for flows to exceed 20-year return period flows on these rivers over the weekend or into next week. These are also rivers that experienced extensive forest fires within their watersheds in 2017, and this expected to increase the likelihood of flooding.


Similar high flow conditions are expected on local tributary streams throughout the Central Interior, including areas around Merritt, Cache Creek, Quesnel, Williams Lake and surrounding areas.
Snowmelt rates will increase through Friday, with on-going rises in river levels expected into the weekend. While temperatures are expected to cool over the weekend, increasing areas contributing to snowmelt runoff and the potential for showers through the weekend indicate the likelihood that river levels in affected areas will continue to rise through the weekend.


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

Contact:
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.
  2. Flood Watch: River levels are rising and will approach or may exceed bankfull. Flooding of areas adjacent to affected rivers may occur.
  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.

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