Here are a few photos of Maui's Wailua Falls, along the Hana Highway at the far eastern end of the island, just past milepost 45. This seems to be one of the more popular waterfalls along the highway, despite being out toward the far end of the road, past the town of Hana itself; it's taller than average, somewhere between 80 and 95 feet high, depending on who you ask, plus there's an actual parking lot here, instead of just parking along the shoulder and hoping positive vibes and a general spirit of aloha will keep you from getting run over. I mean, that's usually enough, but there's always a chance you'll encounter that one guy from some uptight East Coast state who's too busy on his phone screaming at his stockbroker to notice people in the road, and his expensive lawyers will try to blame the state for calling this little 1.1 lane road a state highway, leading him to drive as if it was a proper 4 to 8 lane highway like the ones back home, therefore it's not actually his fault. Or something like that, I'm not a lawyer. But I digress.
This is probably something nobody besides me worries about, but I was curious who actually owns the land around the falls here. Maui County's GIS map says the state government owns it, but doesn't specify which agency. The detailed property record for it also just says "State of Hawaii". It's not a state park, and is also not part of the state forest reserve system, but beyond that I'm not really sure, and I don't recall there being any signs around the falls that would clear this up either, and it's all weirdly kind of vague, but maybe it's not a problem in practice, I dunno.
For actual useful info about the falls, you might try its World of Waterfalls page, or this Medium post about a recent visit, or a Pride of Maui guide to waterfalls around the island.