Lewis & Clark Recreation Area, located near the historical Camp Fortunate site, offers shallow margins for snorkelling near the boat docks. The site features both reef and artificial reef structures. Conditions vary, with water temperatures reaching as low as 34-36°F (1-2°C) in early April. Due to the presence of heavy motorized vessel activity, snorkellers must remain vigilant. The site is accessible from the shore and is suitable for beginners, though the overall rating for snorkelling is 1/5. Facilities include parking, toilets, showers, changing rooms, a rinse station, air fills, equipment rental, a cafe, first aid, a dive shop, boat charters, and guided tours.

Armstead Island in the United States is a freshwater site featuring a submerged rocky perimeter that functions as a reef and artificial reef. Accessible by boat or paddleboard, the site offers a secluded environment for snorkelers. Conditions are variable, with visibility heavily influenced by wind. The water temperature is approximately 36°F (2°C), necessitating appropriate thermal protection for all water activities. Divers and snorkelers should be aware of potential boat traffic in the area. Facilities available at the location include parking, toilets, showers, changing rooms, a rinse station, air fills, equipment rental, a cafe, first aid, a dive shop, boat charters, guided tours, and gear storage.

Horse Prairie is a freshwater snorkel site located on the western shore of Clark Canyon Reservoir. It features one of the few sandy entry points on the reservoir, making it accessible for shore entry. The site is suitable for beginners, though conditions vary due to the fine sediment, which is easily disturbed and can reduce visibility to less than 3 feet. Water temperatures are cool, ranging from 2-13°C in spring and 15-21°C in summer. Wetsuits are recommended to prevent hypothermia during prolonged exposure. Facilities at the site include parking and toilets.

Lone Tree Shoreline is situated at the southern end of Clark Canyon Reservoir where the Red Rock River enters the water body. This freshwater site is characterised by very shallow depths and is prone to high turbidity and siltation. Due to these conditions, it is considered a poor location for snorkelling, though it offers interest for those observing river-to-lake transitions. Water temperatures are very cold, typically ranging from 1-5°C in early April. Divers and snorkellers should be aware of hazards including cold water and low visibility. Facilities at the site include parking and toilets. Access is via a shore entry.