Category Archives: Ashokan Release Channel Operations

Releases reduced to minimum

Now that contractors have finished installing one siphon at Gilboa Dam, DEP has decreased the diversions through the Shandaken Tunnel and is stopping the operational releases from Ashokan Reservoir that allowed for installation of the siphon. Ashokan releases are returning to the minimum community release level in accordance with the Ashokan Release Interim Protocol. The Ashokan Release Channel was gradually decreased today from 220 to approximately 10 MGD, with the last decrease at 3:00PM. The current release channel turbidity is 6.5 ntu.

The new siphon was turned on today and is capable of releasing up to 250 MGD from Schoharie Reservoir. The siphon startup was coordinated with Schoharie County and Town of Gilboa officials, NYPA, NYSDEC and the NWS. DEP will use the siphon to help prevent the reservoir from spilling, thereby allowing workers to continue the dam reconstruction in the area below a temporary notch in the spillway, including the construction of a second siphon.

Ashokan releases ramping up today

NYCDEP Bureau of Water Supply will be increasing the release of water from the Ashokan Reservoir through the Release Channel Saturday December 1st. This increased release has been coordinated with NYSDEC and will not exceed 600 MGD and will last for 3 weeks. The purpose of the increased diversion is to temporarily stop the Schoharie Reservoir from spilling in order to complete the construction of at least one of the two new temporary siphons at Gilboa Dam.

The current release channel turbidity is 9.20 ntu. Releases are scheduled to ramp up in 40 MDG increments hourly, reaching 530 MGD by 4:30PM today.

Ulster County Exec comments on planned DEP releases

The Office of the Ulster County Executive issued the following press release regarding NYC DEP’s plan to initiate three weeks of releases into Esopus Creek:


Kingston, NY – According to Mark Klotz, New York State Department of Environmental Conservation’s (NYS DEC) Director of the Division of Water, the New York City Department of Environmental Protection (NYC DEP) plans to install a new siphon at the Gilboa Dam that will replace those used during the reconstruction work on the dam that were damaged during Hurricane Irene, and dismantled. To lower the Schoharie Reservoir, NYC DEP intends to transfer water from the Schoharie Reservoir, through the Shandaken Tunnel to the Upper Esopus Creek and eventually into the Ashokan Reservoir. It is anticipated that the work will take three weeks.

Because of the expected turbidity of the water that will be transferred from the Schoharie Reservoir into the Upper Esopus Creek, NYC DEP requested that NYS DEC issue it a waiver from the water quality standards it must maintain in at the portal or entrance to the Upper Esopus Creek. It is anticipated by the NYS DEC that NYC DEP will release the maximum amount possible, which is approximately 550-600MGD, through the portal and into the Upper Esopus.

The Ashokan Reservoir is approximately 83% full, with the west basin at capacity and spilling into the east basin. Since this proposed work to the Gilboa Dam will result in a large volume of water entering the Ashokan Reservoir, the NYC DEP is also planning on releasing water from the west basin of the Ashokan Reservoir into the Lower Esopus Creek. Such an operational release is also expected to be at the maximum level of 600 mgd.

County Executive Hein stated, “This is yet another example of NYC DEP’s mismanagement outside of Ulster County negatively impacting the people of Ulster County. Over the course of the last year, Ulster County rebuilt 100% of our infrastructure damaged during Hurricane Irene. We accomplished this ahead of schedule and under budget. Yet NYC DEP, only now with the Schoharie Reservoir spilling, seeks to install a siphon capable of lowering the reservoir. Had the NYC DEP planned ahead and done this during the summer months, this would not be necessary now.

NYC DEP’s plan of action is purely operational, meaning that it is going to be accomplished for DEP’s benefit only, not the health or safety of the Lower Esopus or the people Ulster County. Better planning, which considered the needs of Ulster County’s residents and businesses along the Esopus Creek would have reduced the need for these releases. I implore the NYS DEC to hold the NYC DEP accountable for its ongoing disgraceful, environmentally-damaging behavior.”