If you have ever stood on a boat in Lake Huron with blue lips and chattering teeth while your buddy stayed perfectly dry and warm, you know the struggle. In Canada, the question isn’t just about fashion. It is about how long you want your season to last. While the surface of Lake Erie might feel like a bathtub in August, the shipwrecks below tell a much colder story.
Choosing between a drysuit and a wetsuit is the most significant gear decision for anyone serious about scuba diving Ontario. This guide breaks down the thermal reality of our Great Lakes and helps you decide which suit fits your goals and your budget.
Many new divers assume that a warm Ontario summer translates to warm water. Unfortunately, water conducts heat away from the human body 26 times faster than air. Even on a 30°C day in Windsor, the water temperature just 40 feet down can be a staggering 10°C or lower. This phenomenon is known as a thermocline.
In Lake Erie and Lake Huron, the top layer of water stays comfortable for a few months. However, once you descend past the first 30 feet, you hit a “wall” of cold. For those who want to see the best shipwrecks, a 7mm wetsuit often isn’t enough to prevent the “short season” frustration.
Wetsuits work by trapping a thin layer of water against your skin. Your body heats this water, creating a buffer. For many beginners, a high-quality wetsuit is the first piece of exposure gear they buy.
The biggest drawback is the “evaporative cooling” that happens the moment you climb out of the water. Standing on a dive boat in a wet suit with a cool Lake Huron breeze is a recipe for misery. If you dive wet, your season typically starts in late June and ends abruptly in early September. You can read more about the scuba lifestyle and how gear affects your enjoyment of the sport.
A drysuit does exactly what the name suggests: it keeps you completely dry. Instead of water, it uses a layer of air and thermal undergarments to provide insulation.
Yes, a drysuit is an investment. However, a well-maintained drysuit can last 15 to 20 years. A wetsuit used frequently in the Great Lakes typically loses its “loft” and insulating power within 5 years. When you look at the cost per dive, the drysuit often becomes the more economical choice over a decade.
If you are not ready to commit to a drysuit, you must choose the best wetsuit for Great Lakes conditions. Do not settle for a 3mm or 5mm suit intended for the Caribbean.
A 7mm “semi-dry” suit is the minimum requirement. These suits feature specialized seals at the neck, wrists, and ankles to limit water flow. Brands like BARE and Scubapro offer “Ultra” series suits that use infrared technology to bounce your body heat back to you. While these are excellent, they still cannot compete with the bone-dry comfort of a membrane or neoprene drysuit during a deep wreck dive.
The biggest hurdle for many divers is the fear of using new gear. Drysuits require you to manage air inside the suit to prevent “squeeze” and to control your ascent. At Benthic Scuba, we remove that intimidation.
As the only PADI 5-Star IDC in Essex County with a private onsite pool, we allow you to practice your buoyancy in a warm, controlled environment. You can learn how to trim your weights and manage your valves before you ever step foot in the chilly Great Lakes.
If you only plan to dive a few times a year in the height of summer at shallow depths, a 7mm wetsuit will serve you well. However, if you want to join our local community on weekly charters or explore the world-class wrecks that sit in deeper, colder water, the drysuit is the clear winner.
Staying warm isn’t just about comfort; it is about safety. A warm diver is a focused diver who uses less air and has a much better time.
What is the water temperature in the Great Lakes for diving? Surface temperatures can reach 21°C in late summer, but bottom temperatures on shipwrecks often stay between 4°C and 10°C year-round.
Do I need a special certification to use a drysuit? While not legally required, the PADI Dry Suit Diver specialty is highly recommended. It teaches you how to handle air migration and emergency procedures safely.
Can I use my wetsuit in the winter in Ontario? It is not recommended. Even a 7mm wetsuit cannot provide enough protection against the near-freezing temperatures of Ontario waters in the winter months.Is a drysuit harder to maintain than a wetsuit? Yes. You must wax the zippers and keep the seals lubricated. However, Benthic Scuba provides full equipment service and repair to keep your suit in top shape.
