I have been looking at ponds for the past 2 years for my backyard. Nothing that big just a small one. Now that my kids are older I could probably keep some fish in it. Not sure what the dog will to it though. After I have driveway repaved, I may put the plan in action. Wonder if it helps the resale value, though.
Have a plan for mosquitos. And there are backyard predators, birds, cats, foxes and coyotes that will gobble up your fish. Gotta plan for all of that.