The Delaware River rushes by this home in Slateford. There was a minor threat of flooding due to the amount of rain received over the last few days.
By Dan Berrett
Pocono Record Writer
December 26, 2008

Seven different flood-control and environmental-advocacy groups pressed the leaders of four states and New York City to authorize massive releases of water from upstate New York reservoirs in a bid to potentially lessen the risk of flooding along the Delaware River.

In a letter dated Monday, the seven groups asked Mayor Michael Bloomberg of New York and the governors of Delaware, New Jersey, New York and Pennsylvania to direct the Delaware River master to release water from three upstate reservoirs "to the maximum extent feasible" for the next month.

The mayor and governors jointly control the operation of the three reservoirs — Cannonsville, Neversink and Pepacton — according to a 1954 U.S. Supreme Court decree establishing shared governance of the Delaware River.

The New York City Department of Environmental Protection manages the reservoirs. The three reservoirs hold a combined 270 billion gallons of water and supply less than half of the 1 billion gallons of water that New York City uses each day. Releases must be unanimously approved by the governors and mayor, who are known as the decree parties.

"We are asking that the decree parties take immediate action to dramatically reduce the levels in these reservoirs," the letter writers stated in their Dec. 22 missive. "There is no time to waste debating this situation; immediate and decisive action must be taken."
The authors of the letter were the North Delaware River Watershed Conservancy, Friends of the Upper Delaware River, Aquatic Conservation Unlimited, Delaware Riverside Conservancy, Drowning on the Delaware, Residents Against Flood Trends, and Trout Unlimited.

The seven groups that authored the letter espouse the position that three floods along the Delaware River in 2004-06 were exacerbated because too much water was held in the Cannonsville, Neversink and Pepacton rather than being released regularly in larger quantities into the river.

Instead, they say, dedicated empty spaces, or voids, should be maintained in the reservoirs.

When reservoirs are spilling water at the same time that excess rainfall or snow coats the area, it creates "a potentially deadly scenario," the seven organizations warned the mayor and four governors.

The three reservoirs were 96 percent full on Tuesday — well above historical norms for those reservoirs at this time of year.
But only about one-half of an inch of rain, sleet or ice was expected for the area around the three reservoirs over the next five days, according to the National Weather Service.

The flood gauges that measure the height of the Delaware also have been low, generally at about one-third of flood stage, according to the NWS.
"The river is fine," said Gail Pedrick, director of public relations for the Delaware Riverside Conservancy. But she said the same scenario held true in 2006, and that the reservoirs started spilling and then the rain hit. "If the reservoirs are full, we're in trouble," she said.

The departments of environmental protection of New York City and Pennsylvania could not be reached for comment. But officials have been skeptical of the role that reservoirs play in flooding.

One year ago, hydrologist Roger Ruggles, head of civil and environmental engineering at Lafayette College in Easton, released a report that advocates said bolstered their argument that voids in the reservoir would have had a significant impact on flooding.
Ruggles estimated that river crests at the Montague gauge in Milford in June 2006 would have been lowered by six feet if the reservoirs maintained a 20 percent void.

That would have brought down the water level from 32 feet, as recorded during the June 2006 flood, to 26 feet instead. Flood stage at that gauge is 25 feet.

Officials also have noted that the dams, which were built between 1954 and 1964 and meant primarily to guard against drought, are not engineered for massive and quick releases.

This is true, but the problem is not insurmountable, said Diane Tharp, executive director of North Delaware River Watershed Conservancy and a teacher at Barrett Elementary Center. "Additional measures such as siphons can be installed quickly, could double the release rate, and are being used at the City's Gilboa Dam," Tharp said in a statement.

A new plan governing the reservoirs' releases is included in a Flexible Flow Management Program, which was adopted in September 2007.

That plan was developed by the Delaware River Basin Commission, the administrative body that develops river management policy and comprises the four states bordering the Delaware River, and the federal government.
The DRBC said the new plan was meant to help manage the reservoirs for competing uses: water supply, drought management, flood mitigation.

The DRBC also has been leery of making major changes to the rules governing the river before a comprehensive computer model is ready next month. That model will analyze how different factors — rainfall, weather patterns, land conditions and the water levels in the reservoirs, among others — affect flooding in different scenarios, and help shape policy.