Meet at the last Old Croton Aqueduct-fed water treatment plant and discover (in a plant manager-led tour) what happens to water before it arrives in our taps. Address: 25 Fowler Ave., Ossining 10562. Northbound drivers: From Rte. 9A exit at Shady Farm Rd., turn left and then make an immediate right onto Old Albany Post Rd. Drive about half a mile and turn right onto Fowler Ave. At the top of the hill, the chain link fence of the GE campus will be on your right. Drive straight across the Aqueduct trail and continue to the water treatment plant. Or, from Route 9/Highland Ave., turn right onto Old Albany Post Rd. (north of the Ossining Community Center) and proceed as above. Southbound drivers: from Rte. 9/Highland Ave. turn left onto Old Albany Post Rd. and proceed as above. Parking available. Inquiries: Carl Grimm, firstname.lastname@example.org or 914-271-5471.