The hike down to the pools is short, but it's quite a steep and rocky descent. Even though you might be preparing for a swim, be sure to bring sturdy footwear for the hike down over the sharp lava rock. Trail running shoes, hiking boots, or sturdy sandals like Chacos are recommended. Don't attempt this hike in flip-flops.

Do note that even though this is a very popular tourist spot, several people have died here from rogue waves that unexpectedly blast into the shoreline. Never turn your back on the ocean, and avoid this area during high tide or when the surf is high.

Sources: https://imjesstraveling.com/exploring-the-maui-olivine-pools-hawaii/