The lake is a terminal lake. As Jeff Siegfried, community enhancement director of the Watrous Manitou Beach Marketing Group, explains, “It’s called a terminal lake meaning water flowing into it has no way to escape and so the minerals that are in the bed of the lake leach into the water.” Because the water cannot flow out, minerals from the lake bed accumulate, making the water extremely salty—up to five times the salinity of the ocean.

Indigenous peoples were the first to notice the lake’s unusual properties. Oral tradition records that they used the water to treat illnesses such as smallpox. Lionel Sproule, chairman of the Watrous Manitou Beach Heritage Centre, says the people would leave sick members behind while following buffalo, then return weeks later to find them healed.

The high mineral content, especially magnesium, is still believed to aid recovery today. Visitors like Bob Dobko from Rocky Mountain House, Alberta, claim that soaking in the lake helped him regain strength after a hip and later an arm injury.

The lake’s reputation draws roughly 150,000 tourists each year. In addition to the healing waters, the area hosts the Salty Cinema Drive‑In Theater, one of only three remaining in the province. Lane Manson, overseer of the drive‑in, says, “Drive‑ins are not as in vogue, but it is just another experience that goes on here at Manitou that makes us unique and people are willing to travel for it.”