Reservoirs spill billions throughout 9/18 flood

By CHARLIE BUTERBAUGH

RIVER VALLEY — As water levels overcame Upper Delaware River flood stages early in the morning of Saturday, September 18, New York City’s water supply monitors continued to release millions of gallons from the Pepacton and Cannonsville Reservoirs, which feed the Delaware’s East and West Branches.

The New York City Department of Environmental Protection (DEP), the agency that owns and operates the reservoirs for the metropolitan area’s water supply, maintained minimum conservation releases from reservoir dam valves during the entire flood incident, DEP spokesman Ian Michaels said.

The minimum releases deposit 23 million gallons per day from Pepacton and 29 million gallons per day from Cannonsville into the branches, which raised already high Upper Delaware waters that had taken anywhere from four to seven inches of rain in one day, depending on the location.

Between Saturday and Monday, 14.2 billion gallons spilled over the dam at Pepacton and 10 billion gallons spilled over the dam at Cannonsville. The dams are designed to spill in order to prevent the risk of breaking.

Regarding the impact of releasing water during the flood, Michaels said, “Obviously, it has no effect when you’re losing that much water [over the dams].”

Pepacton reached a record height Saturday at 4:45 p.m., measuring at 1,283.44 feet above sea level. The last time the reservoir reached close to that was in 1960, Michaels said.

As of Tuesday evening, the brimming reservoirs were still spilling. They are usually about 77 percent full this time of year.