symbol for low water level 1

Low Water Advisory – Level 1 Condition

Message Number: 2025-04

Issued: December 15, 2025 at 11:00 AM EST

From: NBMCA Duty Officer, Angela Mills

Low Water Advisory – Level 1 Condition indicates that the received rainfall and/or streamflow in gauged watercourses are below normal and have met the Ministry of Natural Resources (MNR) criteria for low water. The Ontario Low Water Response program uses a three-tiered advisory system used to inform the public of local low water conditions where Level 1 is the least severe and Level 3 is the most severe. Level 1 is meant to be the first indication of a potential water supply issue. Voluntary water use reductions are encouraged.

The Low Water Advisory is being downgraded from a Level 2 Condition to a Level 1 Condition. This is an update to the previous Message Number 2025‑03 dated October 8, 2025.

Current Conditions:

Received rainfall at the North Bay Airport climate station for September, October and November was a total of 239 mm this year, which is 75% of the long-term average (1991-2020) of 320 mm. Rainfall was particularly low in August and September with more precipitation in both October and November. This remains within the threshold for Level 1 Conditions.

The 31-day average streamflow at the Chippewa Creek gauge is 0.615 m³/s, 218 % of its lowest average summer month flow of 0.283 m³/s, however this is 101 % of normal for this time of year.

The 31-day average streamflow at the La Vase River is currently 0.462 m³/s, 168 % of its lowest average summer month flow of 0.275 m³/s, however this is 43 % of normal for this time of year.

The 31-day average streamflow at the Wasi River is currently 2.101 m³/s, 207 % of its lowest average summer month flow of 1.014 m³/s, however this is 70 % of normal for this time of year.

Streamflow conditions no longer meet the criteria for Low Water Conditions.

Current water levels can be viewed by searching Station Names “Ottawa River”, “Mattawa River”, “Chippewa Creek”, “La Vase River”, “Wasi River”, and “Lake Nipissing” at https://wateroffice.ec.gc.ca/search/real_time_e.html

There are no criteria for water levels in the Ontario Low Water Response program. Water levels on Lake Nipissing are normal for this time of year as water levels are lowered through the fall and winter per Public Services and Procurement Canada. The water level on Lake Nipissing is regulated by dams operated by the federal government. Current conditions are available at https://www.canada.ca/en/public-services-procurement/services/infrastructure-buildings/bridges-docks-dams/frenchriver-dam.html

Forecasted Conditions:

The 3-month seasonal forecast from Environment Canada indicates conditions for Winter 2025-2026 are likely to be cooler than normal with near normal precipitation. With the ground frozen and air temperatures forecast to remain below freezing, additional precipitation will be stored in the snowpack and have limited impact on drought conditions.

Historic Low Water Conditions:

For comparison, current streamflow conditions are slightly higher than those of early December 2024, during which time a Level 1 Low Water Condition had been confirmed in early November 2024 and extended through to January 2025. The ongoing Low Water Condition was originally confirmed as Level 1 in early September 2025 and upgraded to Level 2 Low Water Condition in October. Other periods of low water where an advisory of Level 1 Low Water Conditions have been issued include: June to August 2021, August 2018, and August 2012. There had not been any previously confirmed Level 2 or Level 3 Conditions in the North Bay-Mattawa watershed.

Risk:

With increased precipitation through October and particularly November, streamflow has rebounded to no longer meet Low Water Condition criteria; however, three-month precipitation remains below normal and remains within Level 1 Low Water Condition criteria.

Due to the lack of rainfall and low water levels across the watershed, all residents are encouraged to continue voluntarily reducing their water consumption, targeting an overall water usage reduction of 10%.

The vulnerability of municipal water supply systems within the North Bay-Mattawa Conservation Authority (NBMCA) area of jurisdiction were assessed through a water budget stress assessment as part of the Drinking Water Source Protection program. All municipal water intakes within NBMCA jurisdiction were determined to have a low level of risk. Municipal water supply issues are not anticipated at this time. Private water systems were not assessed.

Staff at NBMCA will continue to monitor weather and watershed conditions and provide updates as conditions change.

The general public is advised of these messages through the www.nbmca.ca website with the low water status icon and a link to information about current conditions. NBMCA also circulates these messages to local media and social media, posting on Twitter (@theNBMCA), Instagram (nbmcainfo), and Facebook (theNBMCA).

This message will remain in effect until further notice.

Where a Conservation Authority has not been established, the MNR District Office is responsible for local Low Water Response programs. https://www.lioapplications.lrc.gov.on.ca/webapps/swmc/low-water-response/

Media Release

Low water levels

The Low Water Response Program has three condition levels. The levels are based on trends in streamflow and rainfall.

LEVEL 1 CONDITION is the first indication of a potential water supply problem. A Water Response Team (WRT) may be convened. Voluntary water use reductions are encouraged, targeting an overall 10% reduction.

Level 1 is based on the following criteria:

18-month precipitation < 80% of average, or
3-month precipitation < 80% of average, or
Monthly flow < 80% lowest average summer month flow, or

In Spring (i.e., April, May, June) only:

Monthly flow < 100% lowest average summer month flow.

LEVEL 2 CONDITION indicates a potentially serious water supply problem. The WRT may contact individual water users and Permit To Take Water (PTTW) holders to encourage further water use reductions, targeting an overall 20% reduction.

Level 2 is based on the following criteria:

18-month precipitation < 60% of average, or
3-month precipitation < 60% of average, or
1-month precipitation < 60% of average, or
3 weeks with < 7.6mm rainfall, or
Monthly flow < 50% lowest average summer month flow, or

In Spring (i.e., April, May, June) only:

Monthly flow < 70% lowest average summer month flow.

LEVEL 3 CONDITION indicates the failure of the water supply to meet the demand, resulting in progressively more severe and widespread socioeconomic effects. The WRT may ask the province to impose mandatory restrictions on those holding Permits to Take Water.

Level 3 is based on the following criteria: