You do not need waterfall. You need strength, 30 or so ultra balls and surf.
In the Seafoam Islands, east of Cinnabar Island. You need HM Waterfall, though.
you do need hm waterfall for mt. conet.There's a waterfall in mt.conet
you get HM waterfall on route 18
there is no hm waterfall that i know of
If you're talking about getting to the third boulder to push it into the pit, you don't need the hm waterfall. I thought so too, but then just try swimming up the upside down waterfall. It worked for me.
the last one because you need waterfall to enter the elite four
there is a hm called waterfall
You get the HM waterfall in the same cave you get Kyogre
They need HM 04 Strength Surf and waterfall
Articuno is in Seafoam Islands you need the HM Strength to get to it though and the HM Surf also you need the 4th and 5th badge.
find the waterfall and surf into it ( you dont need HM Waterfall)
Jasmine will give HM Waterfall to you at the beach after defeating Volkner.