How can I transport water safely?

I messed up embarking and I do not have a river available for water. There are lakes I want to drain water from the bottom (I'm inside a mountain) and transport it to a hospital. Is there a way I can safely do this? I'd rather not dig downwards to pump up water. I don't want to learn how to use pumps yet and I've already dug 40 z levels down without finding underground lakes.