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While it is possible to reroute water from waterfalls and the ocean to get it where you might like some to appear, Pokemon Pokopia does eventually give you the ability to make water sources and tiles and place waterfalls. It just takes a bit of playing to make it show up, and you need to make sure you have access to Bleak Beach and Piplup first.
How do I get the ability to make water and place waterfalls in Pokemon Pokopia?
Basically, these are tied to an optional series of sidequests in the Bleak Beach area of Pokemon Pokopia and, if you haven’t been helping out Piplup, you’ll never gain that power. Odds are, you already did start this line of missions though, because the first one involved the ability to transform into a Lapras so you could cross water without drowning. (That involves placing a palm tree and four hedges of any kind alongside ocean water.) After clearing enough mud in the area away with Piplup helping by using Bubble on it so you can Water Gun it away, Lapras teaches you that trick and you will go for a brief swim around town with Piplup through the canals.
The second part of this questline involves taking Piplup to see a waterwheel in Bleak Beach. You don’t need to build one. There are already some built in the main area, not far from the Pokemon Center, and another in the closed off area not far from the Area Gate that you can reach by smashing through rocks. This involves the character following you.
The third part is when you start to get to the ability to make water tile sources and place a waterfall in Pokemon Pokopia. After seeing the waterwheel, Piplup’s next request will be a waterfall near the Area Gate entrance where there’s a small pond. However, you can’t do this immediately. First, you need to get a Paldean Wooper to move the area to learn how. On the other side of the pond is some marsh water. You’ll need to place four tufts of tall grass there. Doing so makes the Wooper variant you need to spawn almost immediately.
Wooper then teaches you the trick. When inhaling with Y and near or in water, press ZR. You’ll then suck up the liquid. Walk and jump to where you want to place that water, and you’ll be able to make ponds, rivers, and lakes. For a waterfall, head to heights above the area, then press A to let the water out.
Making the waterfall near Piplup’s little pond finishes this quest, then allowing you to perform that action in any region.
Pokemon Pokopia is available for the Switch 2.
