By SANDY DECKELMAN

CANNONSVILLE - Did you ever drive past a reservoir and wonder what it was all about? How does the reservoir system work? We all know they hold water, and that somehow the water goes from the reservoir to a sink down the line a ways. How does it get there though? What do they do in those little buildings around the reservoir? How much water is actually in there?

Well, as the kick off event for the 2000 Delaware River Sojourn, the Delaware River Basin Commission (DRBC) hosted a tour of the Cannonsville West Delaware Intake chamber and Cannonsville reservoir dam. A presentation on the history and makeup of the dam, as well as tours of the intake chamber and dam, were given. I had some of those questions answered.

In 1931, the Supreme Court issued a decree allowing for New York City (NYC) to build the Neversink and Pepacton Reservoirs. The Supreme Court amended its decree in 1954 allowing the building of the Cannonsville Reservoirs. Cannonsville would provide NYC, via the Delaware Aqueduct System, with approximately 800 million gallons of water per day. It was stipulated that a flow of 170,000 cubic feet per second (cfs) must be maintained at Montague, NJ.

Construction on the dam started in 1955 and water diversions began in 1964. The reservoir was holding 50 billion gallons of water by March 31, 1967. Construction was completed in 1970. The gross storage capacity of the Cannonsville Resivor is 96.7 billion gallons, of which 95.7 billion gallons is available for use. The water shed drainage area for the reservoir is 450 square miles. As of Thursday, June 15, the reservoir capacity is at 102 %, holding 98 billion gallons.

The dam, which holds the reservoir together, is 175 feet high and 2,800 feet long. There are two spillways, a low weir and a high weir. The high weir, or "waterfall," is 1158 feet high and 600 feet long and can spill 250,000 cubic feet of water per second. The low weir building houses the six release chambers of the dam. Water measurements are taken here to assure the flow in the streams below. There are five larger lines and one smaller line. Two of the lines can control the flow release of water by use of throttling valves. Three of the lines are strictly open or closed, and the smallest line, used mostly during the winter, is operated by a system of three valves. Standing on top of the release chambers was an experience I will not soon forget. I could feel the power of the water moving thru the pipes below in the vibrations of the floor.

The buildings along the sides of the reservoir are called intake chambers. The West Delaware Intake Chamber is located in the northern corner of the reservoir. A small building, it houses a chlorination system, chlorination monitoring system, and the broome gate. The broome gate is used when it is necessary to drain the tunnel for inspection and repairs. Chlorination no longer occurs in Cannonsville due to the extreme precautions and extensive training required in handle it. It hasn't since the 1950's. The chlorination system continues to be maintained and could be charged if necessary. The West Delaware tunnel is 44 miles long and 11'4" in diameter. There are three intake chambers at various depths, off of the coast of the reservoir. The tunnel has the capacities of moving 300 and 500 million gallons of water per day thru the Delaware aqueduct system.

It was an awesome feeling, standing at the top of the dam, looking out over 98 billion gallons of water. It makes you appreciate your surroundings. The fact that water from these reservoirs does not have to be processed, because it is so clean, is something upstate New York can take great pride in.