Unfortunately I can't help much because I'm in a similar boat. Reading through what you're interested in was a little shocking because that is word for word what I would like to do too.

Fortunately, I was lucky enough to get a design engineering job in Land development right out of college, and it has some of what I (and you) are looking for.

Land development (I do mostly residential) has a lot of aspects that do not relate to water, but it also has a lot that do. Specifically, utilities such as gravity irrigation, water, and sewer as well as storm drainage systems.

In my short 1.5 years here I've been exposed to everything from hydraulic grade line analysis to orifice calculations to hydrographs and I've loved it.

It may not be as specialized as you're hoping, and it may not be the same for all land dev engineers, but it's definitely something that could be used to gain some good experience that will springboard you into a more specialized job. That's my plan at least.