Nehalem Falls is a river snorkelling site located on the Nehalem River in the Oregon Coast region. This site is suitable only for advanced snorkellers due to the presence of strong currents and the requirement to navigate river rapids. Access is via a shore entry, with the site situated approximately 1207 metres from the shore. Conditions are challenging, featuring low visibility and significant entanglement hazards. Water temperatures are consistently cold, ranging from 9C to 14C throughout the year. Facilities at the site include parking and toilets. Snorkellers should exercise caution when navigating the deep pools below the falls.

Neahkahnie Tide Pools are located at the northern end of Manzanita Beach, where the mountain base forms a series of rocky channels. This shallow reef site is suitable for beginners, with an average depth of one metre and a maximum of two metres. Access is via the shore, and the site features mild currents. Visibility typically ranges from five to fifteen metres. Water temperatures are cold year-round, ranging from 9C to 14C, necessitating the use of wetsuits. Hazards include cold water, rip currents, surge, and surf. Parking is available for visitors. The site is best suited for those comfortable with intertidal environments.

Nehalem Bay South Jetty provides a rocky habitat at the mouth of the river, accessible via a shore entry from the northern tip of Rockaway Beach. The site features a mix of artificial reef, natural reef, and kelp forest structures. Divers should be prepared for depths reaching 12 metres and variable visibility between 5 and 15 metres, which is best during incoming tides. Conditions are suited for intermediate divers due to strong currents, surge, and potential rip currents. Hazards include boat traffic, entanglement risks, and surf. Species recorded around this area include harbour seals, Steller sea lions, various nudibranchs, and ochre sea stars.

Nehalem North Jetty (River Side) is an artificial reef site located on the Oregon Coast. The rocky substrate of the jetty provides a habitat for various marine life. Divers should be aware of strong currents, surge, and boat traffic, with visibility often ranging between 2 and 8 metres. Depths at this site typically vary from 2 to 18 metres, with an average of 10 metres. Due to the challenging conditions, this site is suited for advanced divers. Snorkeling is possible but rated 2/5, and is only recommended during slack tide in calm conditions to avoid the hazards of the jetty bar.

Short Sand Beach is a sheltered reef site located within Oswald West State Park on the Oregon Coast. The northern rocky edge near Blumenthal Falls provides protection from prevailing winds and features kelp patches. Snorkellers can expect depths ranging from 1 to 10 metres, with an average depth of 5 metres. Visibility reaches up to 12 metres, though conditions vary. Access is via the shore. The site is suitable for beginners, though users should be prepared for cold water temperatures between 9 and 14C, moderate currents, surf, and surge. Hazards include jellyfish, sea urchins, and low visibility. Facilities available include parking, toilets, showers, changing rooms, and a rinse station.

Falcon Cove is a marine reef site located off the Oregon Coast near Arch Cape. The underwater topography consists of polished cobblestones and large basalt slabs. Divers can expect shallow depths ranging from 1 to 5 metres, with an average of 2 metres. Conditions are variable, featuring moderate currents, surge, and visibility between 3 and 10 metres. Marine life observed at the site includes Ochre Sea Stars and snails, alongside less frequent sightings of Monterey Dorids, Northern Leopard Dorids, Sea Nettles, Common Moon Jellyfish, and various crab species. Due to cold water, surf, and rip currents, this site is suited for intermediate divers. Shore entry is required.

Arch Rock is a marine reef site located at the southern end of Arch Cape beach, defined by a prominent sea stack featuring a natural arch. The topography consists of the base of the rock and surrounding boulder fields, which create crevices. This site is suitable for advanced snorkellers due to challenging conditions, including strong currents, surf, and low visibility. Water temperatures are consistently cold, ranging from 9 to 15C, necessitating the use of a wetsuit or drysuit. Shore access is available, and parking is provided for visitors. Due to the environmental hazards, this site requires careful planning and experience in cold water conditions.

Castle Rock is a massive basalt sea stack situated approximately 805 metres offshore from the Oregon Coast. This site features deep vertical walls and is suitable for advanced divers and snorkelers. Access is available via boat or kayak. Conditions at the site vary, with visibility ranging from 5 to 40 metres and water temperatures between 9C and 15C. Divers should be prepared for moderate currents, surge, and surf. Due to the exposed nature of the location, hazards include boat traffic, cold water, and low visibility. The site is rated 4/5 for snorkelling, though its advanced nature requires careful planning and experience.