West of Hanalei at Haena Beach Park on Kauai, the snorkeling at Tunnels Beach is an excellent place to explore during low tide. But you've got to work for it since the best snorkeling is well offshore. It is surprising how many snorkelers come to the Makua Beach (aka Tunnels) snorkeling dive site and only venture 25 feet offshore into the very murky waters with only smothered coral formations. The best Tunnels snorkeling is the outer reef about 500 feet offshore across the channel known for its massive 25 foot diameter lobe, mushroom and cauliflower coral formations. While snorkeling Tunnels, you may encounter plentiful green sea turtles, monk seals, yellowstripe cloris, humuhumunukunukuapua’a (Hawaiian state fish aka rectangular triggerfish), white tipped reef sharks, goatfish, porcupine pufferfish, moral eels, parrotfish, tangs and rainbow cleaner wrasse.
While beginner snorkelers at Tunnels will greatly enjoy the reefs close to the far eastern shoreline where there are some reef fish in the murky waters, advanced snorkelers who are strong swimmers will enjoy heading out to the horseshoe-shapped outer reef about 0.25 miles offshore that is clearly visible at low tide. If you are going to snorkel out to the reef, continue walking east to the eastern point before entering the water where the outer reef makes a close approach to shore. Start snorkeling out about an hour before low tide. From September through May, the surf off Tunnels Beach is affected by seasonal northwest swells that kickup the large waves and generate strong currents so make sure to exercise caution.
To reach the snorkeling in Kauai by air, fly into the Lihue airport (LIH). There are direct flights from Los Angeles, San Francisco, Denver, Seattle and Honolulu. While most visitors to the island rent a car, it is possible to use the public bus but keep in mind that its small and slow. Plus, most of the main snorkeling beaches are well off the bus route requiring some hiking. If you do rent a car, make sure to leave the inside empty when at the beach to avoid attracting break-ins.
To reach the snorkeling at Tunnels Makua Beach, head west on Kuhio Highway (SR56) through Kapa'a towards Hanalei. At Princeville, continue west on SR560 through Hanalei for another 5 miles to Haena Beach Park. There is a large parking area at Haena Beach Park. Note, the best snorkeling access is off the road just prior to Haena Beach Park, but there is very limited roadside parking which is filled by 9am. From the main Haena Beach Park parking area, walk to the right heading east along the beach for about 2,000 feet to where the reefs come up to the beach. Since parking is limited, consider taking the newer North Shore Shuttle van from Hanalei which runs regularly.
Before snorkeling at Tunnels Beach, make sure to check the current surf report. The waters off Kauai are known for potentially strong currents, high surf and rogue waves. Luckily, there are excellent up-to-date surf reports that can provide guidance on these adverse conditions. WIth the usually rolling surf, it is strongly discouraged to use open-tube snorkels which are common at snorkel rental locations -- only use snorkels with a dry-top splash-guard and a sump purge-valve in the mouth piece. In addition to changing surf conditions, a Tunnels Beach snorkeling dive may expose you to sharp coral reefs and you may encounter sharks, such as whitetip reef sharks, galapagos sharks and tiger sharks. Most snorkeling shark attacks in Hawaiian waters tend to occur near spear-fishing snorkelers, so be aware of the activities of others in the water.
Overall, Tunnels Beach is the 2nd most popular snorkel dive spot of all 23 snorkeling dives in Kauai.