tips for building bat houses - "chambers at least 14" wide and 24" tall (bigger is better), and a wide landing area with a very rough surface beneath the entrance. Do not use pressure treated lumber. These furry little creatures prefer temperatures between 85°F and 100°F."
I'd entertain the thought of this running from our downspout/sump pump drain, across the side yard, and down to the street. Then, the path from the driveway to the backyard could have a bridge over this. Too much for the front yard?
Making A Dry Creek Bed Drainage Canal for Downspouts