Our lakes are great places to relax, cool down, and have some family time during the summer. But bacterial infections such as E. coli can put a damper on the fun. Our role is to monitor public beaches within the city and district (with the exception of beaches within provincial parks) and alert the public of high levels of E. coli and other hazards which may make swimming unsafe for the public.

BEACH NOTIFICATION - Please visit the beach notification page to learn of any beach notifications.


What We Do

Public Health Inspectors from the Thunder Bay District Health Unit (TBDHU) monitor public lakes throughout the summer in both the City of Thunder Bay and throughout the District to measure E. coli levels and inspect for other health hazards.

  • We sample for water quality at three beaches supervised by the City of Thunder Bay weekly from the end of June to the end of August. These beaches include the Main Beach at Boulevard Lake and two beaches at Chippewa Park (Main Beach and Sandy Beach).
  • Outside of Thunder Bay, we sample for water quality at district beach locations once in July and once in August. See below for a list of district beaches.


City of Thunder Bay Beaches

Signage at City Beaches

Permanent swimming advisory signs are posted at Boulevard Lake and Chippewa Park beaches letting the public know of the likelihood that the water has elevated levels of E. coli, based on five years of previous water quality tests. The new signs will help the public make decisions about the risk of harm to their health due to E. coli at any time they are considering a swim.

How to Interpret the Signs

The signs provide the public with a long-term summary of E. coli test results over the past five years. So if the sign says 30%, this means that approximately 30% of the tests taken over the last 5 years at that beach had elevated levels of E. coli. People can use that information to decide if they want to swim at that beach.

What the public will see

The signs posted at Boulevard Lake and Chippewa Park beaches show the percentage of water quality tests that indicated elevated levels of E. coli. The signs have been updated in 2023.

Beach Signage
Beach   What the posted sign means
Boulevard Lake Main Beach


Approximately 10% of the tests taken over the last 5 years at Boulevard Lake Main Beach had elevated levels of E. coli
Chippewa Park Main Beach


Approximately 10% of the tests taken over the last 5 years at Chippewa Park Main Beach had elevated levels of E. coli.
Chippewa Park Sandy Beach


Approximately 0% of the time, Chippewa Sandy Beach had elevated levels of E. coli.

District Beaches

Swimming Advisory Signs

The TBDHU uses temporary advisory signs at district beaches as these beaches rarely have elevated levels of E. coli. If a water quality test shows elevated E. coli levels, a sign will be posted and then removed when further tests show the levels are no longer elevated. See below for a list of the beaches monitored.

What is the risk of elevated levels of E.coli?

  • Swimming in water that contains higher levels of E. coli increases the risk of developing minor skin, eye, ear, nose and throat infections, or gastrointestinal illness.

Will the TBDHU close beaches?

Beach closures are rare. A beach closure (as opposed to an advisory) is issued when an immediate and significant health hazard is present. This could be a sewage spill, a toxic chemical release or a visible bloom of blue-green algae in the water. Should this happen, the public will be informed through local media, including social media. Beach closure signs will also be posted.


Reducing the Risk of Infection

To reduce your risk of infection or illness at a public beach:

  • Avoid swimming 24-48 hours after heavy rainfalls.  Rain can carry bacteria from the street, parking lot and shoreline and flush it into our beaches causing potential contamination
  • Avoid swallowing beach water at all times
  • Assume swimmer's itch is present and always towel off after a swim and shower once at home
  • Do not feed birds and place garbage in the garbage cans provided
  • Keep in mind that E. coli tests can take up to 24 hours, so an advisory is based on the results of samples taken on the previous day
  • The advisory sign (or lack of an advisory sign) may not reflect the current conditions present in the water because E. coli levels in recreational water can vary from hour to hour


List of Beaches

Thunder Bay

  • Boulevard Lake - Main (Lakeview)
  • Chippewa Park - Main Beach and Sandy Beach

District Beaches

Please visit the beach notification page to learn of any beach advisories for these beaches:

  • Shuniah - Wild Goose Beach, O'Connor Point, West Loon Lake
  • Neebing - Cloud Lake, West Oliver Lake, East Oliver Lake
  • Nipigon - Lofquist Beach
  • Schreiber - White Sand Lake Beach
  • Terrace Bay - Aguasabon Beach
  • Terrace Bay - Dock Side, Pump House Beach
  • Marathon - Carden Cove, Lions Penn Lake Park
  • Manitouwadge - Manitouwadge Lake
  • Longlac - Jeff Gauthier Memorial Park
  • Geraldton - Kenogamisis Fish and Game, Geraldton Waterfront
  • Nakina - Cordingley Lake
  • Beardmore - Poplar Lodge

Please note: the TBDHU is not responsible for routine monitoring of private beaches or beaches within provincial parks and conservation areas.

For advisories about beaches at provincial parks, please visit the Ontario Parks Alerts page.

For advisories about beaches at conservation areas, please visit the Lakehead Region Conservation page.


For Further Information

Call a Public Health Inspector: (807) 625-5930

or toll-free 1-888-294-6630, ext 5930


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