Rapids in Mountains biomes

The current mountains are amazing, and I have seen small water sources that turn into cool gorges that continue out to sea, but what I haven’t seen were large, or really even moderate water sources in mountains. And I think a good way to fix this would be to add some sort of rapids that can start some distance from the peak, beginning with some watery streams like the ones that generate with gorges currently, that merge and become a rapid. Occasionally there could also be a small waterfall, 5-10 blocks tall, like ones kayakers fear irl. There could also rarely be large waterfalls that generate near the end of the rapids, which has a pool of water below and either a continuation of the rapids or the start of a river.