Sorry for the late response Cathy, still working through problems with the computer crash. Best I can determine is that it is a Marmot. I've been back a few more times and have seen it each time.

But to be honest this just does not fit. It's a small burrow with no dirt mound at all which is not typical. Plus it's in a flat open waterland area not hilly country like you normally find marmots in. I only see one hole and it's about 6" across which is small for a marmot. Still haven't got a good look at it's tail though and that may help some.