Category Archives: Ashokan Release Channel Operations

Releases resume as stream gauge level subsides

The DEP notified local officials that releases will resume today, distributing the following statement:

NYCDEP Bureau of Water Supply will begin releasing water from the Ashokan Reservoir through the Release Channel starting today. The release will be ramped up to a rate not to exceed 600 million gallons per day. Activation of the release channel is made to create more room in the reservoir to capture projected runoff and will help to minimize impacts to the water supply. Such releases have the added benefit of further enhancing the flood protection the reservoir already provides downstream. We will continuously monitor the release rates and adjust as necessary. Additional notifications will be made as required. Thank you for your cooperation.

Releases were shutdown yesterday evening when the Mt. Marion Stream gauge reached “Action Stage.” Now that the stream level has dropped, releases are allowed by the Interim Release Protocol, which provides for “Operational Releases” to prevent spilling of turbid water from the West Basin to the East Basin of the Ashokan Reservoir.

Release channel closed in response to stream gauge level

The Ashokan Release Channel was decreased 240 to 0 MGD. The decrease was made in one step at 1930hrs. This decrease was required as per measurements at Mt. Marion Stream Gauge. The current Ashokan Release Channel turbidity is 28.00 NTU.

According to the Interim Release Protocol, the release channel must be shutdown when the USGS gage on the Esopus Creek at Mount Marion (Lower Esopus) is within 1 foot of the “Action Stage” (18′) and is forecasted to reach “Action Stage”, as predicted on the NWS’s Advanced Hydrologic Prediction Service web page.

DEP ramping up releases

New York City DEP announced that it will begin ramping up releases today in anticipation of increased rainfall runoff. The DEP notified local officials via email with the following statement:

NYCDEP Bureau of Water Supply will begin releasing water from the Ashokan Reservoir through the Release Channel starting today. The release will be ramped up to a rate not to exceed 600 million gallons per day. Activation of the release channel is made to create more room in the reservoir to capture projected runoff and will help to minimize impacts to the water supply. Such releases have the added benefit of further enhancing the flood protection the reservoir already provides downstream. We will continuously monitor the release rates and adjust as necessary. Additional notifications will be made as required. Thank you for your cooperation.

Under the Interim Release Protocol, the DEP is allowed to make “Operational Releases” to prevent overspill of poor quality water from the West Basin into the East Basin of the Ashokan Reservoir.

Ashokan Release Channel Operations 3/28/12

The Ashokan Release Channel was decreased today from 10 to 0 MGD at 8:47AM.

In accordance with Ashokan Release Interim Protocol Section 7.c. Exceptions, DEP is temporarily stopping the Ashokan Release in order to install flow-monitoring equipment in the release channel and perform engineering inspection of release channel walls. This work is expected to take 3 successive workdays. The release will be resumed at night provided it will not damage work in progress.

The installation of the flow metering equipment will improve the ability to measure future release rates. The engineering inspection will be used to develop designs for repairs to the 100 year old walls which DEP wants to perform in the near future.