If you design the water garden's bed to be about 1 inch deep, it will become the center of bird activity, especially in the fall and winter, so it is a great project to start now:
Using a recirculating pump, create a waterfall that trickles to a creek area, letting the water splash from rock to rock as it makes its way down the falls. Use a heavy-duty PVC liner for the creek bed that drops away from the falls, then cover the bed with pea gravel. Line the creek edges with rocks, and create shallow pools to serve as bird bathing areas.
As warmer weather turns to winter, you'll notice birds busying themselves at the water. When all the other puddles and water sources are covered with ice, the birds know they can sip and dip at your bird creek. One advantage of keeping water in winter is seeing the winter migrants visit it as well.