Drought conditions have eased in the larger rivers of the Thompson watershed, but not in smaller streams or aquifers. The BC River Forecast Centre’s October 19 reports show the Thompson River near Savona within the normal range for this time of year, while several tributaries are flowing at the lowest levels ever recorded for the date.

Rivers and streams

The Centre compares each station’s average flow over the past seven days with the same week in that station’s historical record. A percentile of 50 is typical; the lower the number, the lower the flow is compared with past years. Drought levels from 0 to 5 are based on those percentiles, so they differ from the basin-level ratings on the provincial Drought Information Portal.

Station	7-day flow percentile	Drought level
Thompson River near Savona	36	0
North Thompson River at McLure	42	0
South Thompson River at Chase	21	1
Thompson River near Spences Bridge	26	1
Adams River near Squilax	17	2
Coldwater River at Merritt	12	2
Bonaparte River below Cache Creek	3	4
Nicola River below Nicola Lake	2	5
Bessette Creek above Beaverjack Creek	2	5
Salmon River near Salmon Arm	Lowest recorded	5
Chase Creek above the mouth	Lowest recorded	5

Source: BC River Forecast Centre, Thompson-Okanagan Low Streamflow Report, October 19, 2026.

The Nicola River below Nicola Lake is just above its record low for the date: its seven-day flow was 0.49 cubic metres per second on October 19, against a record low of 0.46 for the same week.

What it means for fish

The Centre notes that when a stream’s flow falls below 10% of its long-term average, there is less riffle habitat, the shallow, fast-moving stretches that produce food for fish and add oxygen to the water. Flows near 5% of average may call for restrictions on water use. On October 19, the Nicola River below Nicola Lake (9%), the Coldwater River at Merritt (8%), and Guichon Creek at the outlet of Mamit Lake (6%) were all below the 10% mark.

Water temperatures have eased. No monitored stream in the region averaged above 20°C over the past week. The Centre treats a weekly average of daily highs above 20°C, or a daily high above 23°C, as thresholds that can trigger fisheries closures and water use restrictions. The province’s fish and drought summary for the region explains that, in general, low flows and warm water can stop fall-spawning fish, such as coho, Chinook, sockeye, kokanee, and bull trout, from reaching their spawning habitat.

Groundwater

Of the 31 observation wells reporting across the Thompson-Okanagan, 13 are at the lowest levels on record for this date, 4 are much below normal, 2 are below normal, and 12 are in the normal range. The record lows include several wells near Enderby, Armstrong, Lumby, and Spallumcheen, and one near the Salmon River. Many Thompson-Nicola wells have not reported recent data, so the picture there is less complete. Of the two Merritt wells that did report, one is in the normal range and the other, which has a shorter seven-year record, is at a record low.

What recovery needs

The province’s August 20 drought bulletin noted that recovery next year may require wetter-than-normal conditions and a late freshet, the spring snowmelt that feeds rivers. The Pacific Salmon Foundation adds that an El Niño that formed in June is forecast to become a record-strong event, and that El Niño years tend to bring weaker snowpack and lower streamflows to BC.

Where to find the data

The Centre’s Low Streamflow Report and Groundwater Report cover the Thompson-Okanagan region, and the BC Drought Information Portal shows provincial conditions. The Centre notes that its data are provided as is and may be unverified or uncorrected.

Related reading

IndigiNews’s feature on the Nicola River speaks with Brian Holmes, Upper Nicola Band councillor, about this year’s drought in the Nicola watershed.