Ministry of FLNRO

Flood Warnings and Advisories

UPDATE - High Streamflow Advisory – South Coast (MAINTAINED)
ISSUED: November 23, 2017 12:00 PM

The River Forecast Centre is maintaining the High Streamflow Advisories for:

  • Howe Sound including the Stawamus River, Squamish River and tributaries in the Squamish area
  • Sea-to-Sky including the Lillooet River and tributaries in the Whistler and Pemberton area
  • North Shore Mountains including the Seymour River and surrounding tributaries
  • Fraser Valley including the Chilliwack River, Coquihalla River and surrounding tributaries

Rain and snowmelt over the past two days has led to high streamflow conditions throughout the region. In smaller rivers, and along the North Shore Mountains, flows have generally peaked from this runoff, and are now receding. On the larger rivers, flows still remain elevated, and are at or near peak levels as of mid-day Thursday. This includes the Squamish River, Lillooet River, Cheakamus River, Chilliwack River, and Coquihalla River. Additional rises (20-50 cm) are possible Thursday afternoon on the Squamish River and Lillooet River. Depending on rainfall amounts this afternoon, higher flows are also possible on the Chilliwack and Coquihalla Rivers. Flows will remain elevated through the rest of Thursday and are expected to recede into Friday.


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


 A High Streamflow Advisory means that river levels are rising or expected to rise rapidly, but that no major flooding is expected.  Minor flooding in low-lying areas is possible.
 A Flood Watch means that river levels are rising and will approach or may exceed bankfull.  Flooding of areas adjacent to affected rivers may occur.
 A Flood Warning means that river levels have exceeded bankfull or will exceed bankfull imminently, and that flooding of areas adjacent to the rivers affected will result.