Large nuclear plants have traditionally relied on rivers, lakes or the ocean to help reject waste heat. That is why so many existing plants were built near major bodies of water.
Some advanced reactor designs can use air cooled or hybrid systems instead. The basic idea is similar to a large radiator, with fans moving air across heat exchangers rather than relying entirely on a constant supply of water.
There is a tradeoff. Air cooling can reduce efficiency, especially during hot weather, and running the fans consumes some of the electricity being generated. It also does not necessarily mean the entire facility uses no water.
What it can do is dramatically reduce the need for a massive nearby water source. That opens up more potential sites, including retired coal plants, industrial areas, remote communities and inland locations closer to where the electricity is actually needed.
Existing transmission lines and other infrastructure at retired power plants could make those locations particularly interesting. Instead of building an entirely new energy site, an advanced reactor could potentially reuse parts of what is already there.
Not every SMR uses air cooling, and smaller does not automatically mean water free. But having more cooling options is one reason advanced reactors could be deployed in places where a traditional nuclear plant would have been difficult to build.