The North Bay-Mattawa Conservation Authority relies on a network of monitoring sites to track hydrological, meteorological, snowpack, water quality, aquatic biology and groundwater conditions within its jurisdiction. 

Data is generated to satisfy both short- and long-term interests for watershed management, flood forecasting and program planning.  Monitoring is undertaken using electronic gauges which collect data frequently and support real-time monitoring needs. Data is also collected biweekly or monthly through field sampling usually undertaken on a seasonal basis.

NBMCA relies on timely access to data so it can issue advisories and warnings when water levels, streamflow, and weather conditions raise concerns for the safety of people and property.  Data is archived to serve comprehensive watershed management interests and support of the goals of NBMCA's Integrated Watershed Management Strategy.

Watershed monitoring is needed to identify watershed health issues and stresses that are impacting the environment. This information can then be used to shape our other programs. 

An adequate water supply is critical for all life. NBMCA monitors and reports on water quantity and quality throughout our watershed in cooperation with the Water Survey of Canada, Ontario Ministry of Environment, Conservation and Parks, and the Ministry of Natural Resources and Forestry.


Water Quantity

One of NBMCA's main goals is to reduce the threat of loss of life and property damage from flooding. This is done through Flood Forecasting, flood warnings, and the operation and maintenance of flood control structures.  Changes in flow regimes and water quantity can impact human and aquatic health and economic activity. 

NBMCA assesses water quantity through review and/or monitoring of surface water levels and flows, groundwater levels, snow depth and water equivalence, and precipitation.  These activities are in partnership with Environment and Climate Change, Ontario Ministry of Natural Resources and Forestry and Ontario Ministry of Environment, Conservation and Parks.

  • Surface water levels are monitored continuously at 9 locations
  • Streamflow modelled for 4 locations (Water Survey of Canada’s site)
  • Groundwater levels are monitored continuously in 6 subwatersheds
  • Snow depth and water equivalence measured routinely in 3 subwatersheds

Water Quality

Provincial Water Quality Monitoring Network (PWQMN)

The PWQMN collects water quality information from rivers and streams at more than 400 locations throughout Ontario in partnership with the Ministry of Environment, Conservation and Parks (MECP). The water samples are analyzed for approximately 40 general chemistry parameters such as metals and nutrients at the MECP lab, while other measurements such as, dissolved oxygen, and turbidity are taken with a hand-held sensor.  NBMCA samples at nine local PWQMN stations on a monthly basis between April and November, annually.  Select sites are also sampled through the winter.  Sampling began at some of these sites in 1968 and data can be downloaded from the Ontario Provincial Water Quality Monitoring Network or DataStream.

Integrated Watershed Management Stream Water Quality Monitoring

Twelve additional stream water quality have been established (most in 2018) to supplement the existing monitoring conducted through the PWQMN, expanding coverage through NBMCA’s subwatersheds.  These streams are sampled for total phosphorus, temperature, pH, specific conductance, dissolved oxygen, and turbidity on a monthly basis, from April through November, each year.  Chloride sampling began at these sites in 2022.

Provincial Groundwater Monitoring Network (PGMN)

The PGMN is a network of almost 400 wells located across Ontario in partnership with MECP that monitors groundwater levels and groundwater quality.  The groundwater level and temperature readings are taken hourly and are stored in a data logger for manual download. This data is maintained by MECP and is made available for use by partner Conservation Authorities.  Groundwater quality samples are collected every year in the fall and analyzed for general chemistry and metals at the MECP labs. Wells are visited several times a year to check equipment, take manual static level measurements and download data. 

NBMCA monitors groundwater level at six monitoring wells located across the watershed, and samples water quality from four wells.  Two shallow wells are sampled every year and two deep, high-volume wells are sampled every second year.  The location or extreme depth of the other two wells prevent sampling.  Data from these wells is available, some since 2003, and can be downloaded from the Ontario Provincial Groundwater Monitoring Network.

Lake Monitoring Program

NBMCA monitors the water quality of local lakes as a Science Partner in the Ministry of Environment, Conservation and Parks (MECP) Lake Partner Program.  Four priority lakes – Trout Lake (8 sites), Lake Nosbonsing (7 sites), Callander Bay (1 site), and Wasi Lake (1 site) – are sampled regularly throughout the ice-free season every year; other lakes (10 lakes with combined 17 sites) are monitored on a rotating basis. Lake water samples are analyzed for total phosphorus by the MECP’s Dorset Environmental Science Centre and measurements of turbidity (clarity), temperature, pH, specific conductance, dissolved oxygen, and chlorophyll and cyanobacterial pigments are taken with a Secchi disc and multi-sensor sonde lowered to the lake bed.  Monitoring of Trout Lake is conducted in partnership with the City of North Bay.  Total Phosphorus and Secchi depth data are available from Ontario Lake Partner Program and DataStream.                             

Aquatic Biology

Ontario Benthos Biomonitoring Network (OBBN)

Benthic macroinvertebrates are the small creatures that live in stream sediments, don't have a spine, and are large enough to see without magnification (eg., insects, ;arvae, molluscs, etc.).  They are sensitive to environmental impacts such as pollution and habitat degradation and are an important part of aquatic food webs (e.g., supporting fish production).  In this way, benthic community structures are significant in determining the ecological health of aquatic ecosystems. Benthic sampling is conducted by NBMCA each spring at four locations within the Chippewa Creek subwatershed, and rotationally at tweleve streams within other subwatersheds.  Taxonomic identification is completed by microscopy to the family level, and the data are used to quantify ecosystem health. Data can be downloaded from Ministry of Environment, Conservation and Parks Ontario Benthos Biomonitoring Network.

Watershed Report Card

Every five years, NBMCA issues a Watershed Report Card (WRC) for its 20 subwatersheds.  It is based on a set of indicators established by the technical staff of Conservation Ontario and Ontario's 36 Conservation Authorities, and reports on four resource categories: surface water quality (streams/rivers), groundwater quality, forest conditions and, wetland cover.  For more information, visit the Watershed Report Card section of the website.