Surface Water Quality

The RVCA has gathered information on surface water quality since the early 1970s. Today, the RVCA collects data four water quality monitoring programs:

  • Provincial Water Quality Monitoring Network (Water Chemistry)
  • RVCA Baseline Monitoring Program (Water Chemistry)
  • Watershed Watch (Water Chemistry)
  • Benthic Invertebrate Sampling (Water Biology)

Results from these monitoring programs are reviewed and reported on through our catchment and subwatershed reports.

Water Chemistry

The Rideau Valley Conservation Authority monitors water chemistry at 57 stream locations and approximately 39 lake locations for a total of 409 sampling sites throughout the Rideau watershed on a routine basis.

The three water chemistry monitoring programs are:

  • Provincial Water Quality Monitoring Network
  • RVCA Baseline Monitoring Program
  • Watershed Watch

Information on water chemistry is available through our catchment and subwatershed reports and our interactive mapping tool.

Provincial Water Quality Monitoring Network (PWQMN)

This program looks to provide a consistent baseline dataset that can give a general indication of water quality in the watershed. Details: Provincial Water Quality Objectives.

  • 10 sites throughout the watershed ( 6 sites are in common with the City of Ottawa monitoring program and 3 with the RVCA baseline program which increases the total dataset for those sites which can allow more detailed assessment)
  • 8 times per year about once a month spaced to collect samples from the complete range of flow conditions from April to November
  • 36 sample variables including nutrients, metals and ions

RVCA Baseline Monitoring Program

The RVCA Baseline Monitoring Programs looks to assess the contribution of tributary streams to loadings in the Rideau River and upper watershed lakes. It also monitors ambient conditions at locations on major tributary streams.

  • 56 sites in total
  • 8 times per year about once a month spaced to collect samples from the complete range of flow conditions from April to November
  • 31 sample variables including bacteria, nutrients, metals, dissolved solids and ions

Watershed Watch Program

The Watershed Watch Program samples the 39 major lakes in the watershed on a regular cycle to help identify trends in water quality. The program relies on volunteers to help with water transport or boat/canoe access points. Learn about getting involved in the Watershed Watch Program.

  • average of 8 sites (varies each year depending on lakes); 1 site at lake deep point (surface and bottom samples, dissolve oxygen/temperature profiles), average 4 inshore sample sites near possible pollution source points/areas
  • samples taken once in May, September, October; twice during summer months (June-August)
  • sample variable include total phosphorous (TP), total Kjeldahl nitrogen (TKN), dissolved organic carbon at deep points; TP,TKN, Eschericia Coliform (E.Coli.) at inshore sites (sampled at half metre depth in approximately one metre of water)

Water Biology

Benthic invertebrates include:

  • aquatic insects (e.g. stoneflies, mayflies, caddisflies, beetles, true bugs, true flies)
  • crustaceans (e.g. isopods, amphipods, crayfishes)
  • molluscs (e.g. snails, clams, mussels)
  • annelids (e.g. leeches, oligochaete)
  • and a few other groups (e.g. proboscis worms, flatworms)

common inverts

The Rideau Valley Conservation Authority has sampled benthic invertebrates since 1997 at various sites throughout the watershed. These efforts compliment the RVCA's extensive water chemistry sampling program. Benthic invertebrates are great barometers of pollution. Some can tolerate pollution while others are very sensitive to instream pollution. By sampling stream-bottom invertebrates the program can determine changes in stream water conditions and levels of pollution over time.

As part of the Ontario Benthos Biomonitoring Network (OBBN), RVCA staff follow a provincial protocol for sampling in streams, lakes, and wetlands. A total of three replicates of samples are collected at each of the site locations and are brought back to the RVCA lab for identification. Once identified the samples are run through various indices, which are then analyzed and observations can be made. Overtime trends and patterns of the data can be studied and water quality issues can be addressed by using best management practices in areas of concern.

Results from our water biology sampling can be seen in catchment and subwatershed reports.

Contact Us

Rideau Valley Conservation Authority
3889 Rideau Valley Drive
Manotick, Ontario K4M 1A5

613-692-3571, 1-800-267-3504


Monday to Friday, 8:30 a.m. to 4:30 p.m.

Member of: conservation ontario