Head out the canal towards Pittsford. In the village, go past the railroad trestle and turn right into the Town Highway Department drive. Pick up the trail on the left that will connect over to the Auburn Trail. Cross over French and follow the trail until you are across the street from the Springhouse Commons. Cross over 31 and pick up the old Erie Canal Trail that runs behind Wegmans. Follow this back across French Rd and connect back with the Barge Canal, and follow the canal all the way back to the Basin. Distance is 11.6 miles.
http://www.gmap-pedometer.com?r=6769293
For around 8 miles, stay on the canal to the 2nd time Rt 31 crosses the canal, turn around and retrace your steps.
For 14.8 miles, follow the standard route. When the Old Erie Canal reconnects with the Barge Canal, turn right and run over to the JCC. Turn around and run all the way back to the basin along the towpath.