The Julia B. Merrill is a freshwater wreck located in Lake Ontario, resting at a consistent depth of 18 metres. This site is suited for intermediate divers with strong buoyancy control, as the structure presents an entanglement risk during penetration. Visibility is variable, ranging from 3 to 10 metres, and water temperatures fluctuate between 3 and 15 degrees Celsius, necessitating drysuit use. The site experiences mild currents, but divers must remain cautious of active surface boat traffic. Access is exclusively by boat, and the use of a delayed surface marker buoy is essential for a safe ascent. Guided tours are available through local charter operators.

The Sligo is a freshwater wreck located 2500 metres offshore in Lake Ontario. Resting at depths between 19 and 30 metres, with an average of 25 metres, this site is suited for intermediate divers. The wreck provides an overhead environment that requires careful buoyancy control and the use of a reel or line. Visibility typically ranges from 5 to 15 metres, though conditions can change rapidly. Water temperatures are cold, fluctuating between 3 and 15 degrees Celsius, necessitating appropriate thermal protection. Boat access is required to reach the site, and divers should be aware of potential boat traffic, entanglement hazards, and the risks of nitrogen narcosis at these depths.

Humber Bay is a freshwater artificial reef site located in the Niagara Peninsula. Divers access this site from the shore for dives typically lasting around 50 minutes. The site features depths ranging from 5 to 15 metres, with an average depth of 10 metres. Conditions are variable, with visibility fluctuating between 2 and 18 metres and mild currents. Water temperatures are cold, ranging from 3C to 14C throughout the year, necessitating appropriate thermal protection such as drysuits. Facilities available at the site include parking and toilets. This location is suitable for beginner divers, though they should be prepared for cold water and potential low visibility.

Lakefront Promenade Park features a man-made, protected swimming inlet in Mississauga. The site is characterised by a sandy and silty bottom, with rock-lined edges that serve as an artificial reef structure. With depths reaching up to 3 metres, the inlet provides a calm environment suitable for beginners and snorkellers. Water temperatures vary significantly throughout the year, ranging from 4C in winter to 21C during the peak summer months of July and August. The inlet is generally warmer and shallower than the surrounding Lake Ontario. Shore access is available, and the site includes facilities such as parking, toilets, showers, a cafe, and first aid stations. Cold water remains a primary hazard outside of summer.

J.C. Saddington Park offers shore-entry snorkeling along the Niagara Peninsula shoreline. The site is defined by heavy rock rip-rap, where large armor stones create an artificial reef structure. Snorkelers can explore the gaps between these stones, which provide habitat for local fish. Water temperatures in Lake Ontario fluctuate significantly, ranging from 4C in winter to 21C during peak summer months. Due to the cold water and potential for surf, this site is best suited for intermediate snorkelers equipped with appropriate thermal protection. Facilities at the park include parking, toilets, showers, changing rooms, and a rinse station.

Richard's Memorial Park at East Cove offers a freshwater snorkelling experience along the Niagara Peninsula. The site features a rocky headland at the eastern end of the beach, where stone armour and natural lakebed rocks create crevices that attract various fish. Water temperatures fluctuate significantly throughout the year, ranging from 3C in winter to 21C during the summer months. Entry is via the shore, making this a suitable location for beginners. Facilities including parking, toilets, and showers are available on-site. Be aware that conditions can include surf and low visibility. Species recorded around this area include trout, alewife, white sucker, common carp, round goby, sun perch, American crayfish, spotfin shiner, rudd, bluntnose minnow, pike, and small mouth bass.

Jack Darling Memorial Park, specifically the Rocky Point area, offers shore-accessible freshwater snorkelling in Mississauga. The site features a varied topography consisting of sandy patches interspersed with large submerged boulders. The rocky sections located to the west of the main swimming beach are generally preferred for better visibility and higher concentrations of aquatic life. Water temperatures fluctuate significantly throughout the year, ranging from 3C in winter to 21C during the summer months. Species recorded around this area include white sucker, alewife, common carp, round goby, trout, bluntnose minnow, pike, rudd, American crayfish, spotfin shiner, sun perch, and various snails.

Rattray Marsh features a unique natural shale beach and a flat stone lakebed at the edge of a significant wetland. This freshwater site is suitable for intermediate snorkellers, offering depths between 1 and 5 metres with an average of 3 metres. Entry is via the shore. Conditions include mild currents and visibility ranging from 1 to 5 metres, which can be affected by organic matter from the marsh. Water temperatures fluctuate significantly throughout the year, reaching up to 21C in summer, though thermoclines can cause temperatures to drop to 4-7C. Hazards include potential entanglement and low visibility. Species recorded around this area include alewife, white sucker, trout, round goby, common carp, and pike.