Grubb Road North Lima, Ohio 45806Williams Reservoir webpage
Also, see all the hotspots at:
Metzger and Ferguson Reservoirs Important Bird Area
Allen County Birding Drive
Williams Reservoir holds 5.1 billion gallons of water with a depth of 858.0 feet when full. The distance around is 3.7 miles.
From Williams Reservoir webpage
There is a description and map of a 5.8-mile hike at the Williams Reservoir on the AllTrails website.
No restroom facilities.