Wilmington Flume features four drops in the West Branch of the Ausable River, near High Falls Gorge.
Take Route 86 southwest from the point where NY 73 and CR 431 intersect in Wilmington. Continue for just under 2 miles and you'll see a parking lot on your right. If you cross the Ausable River, you've gone too far.
You need only walk a few hundred feet from the parking area to get to the bridge where you can see part of the falls.
If you want to get a closer view, follow the signs for the trail that will bring you down to river-level.