The citizens' not-for-profit advocacy group for the Gilboa Dam and Schoharie Reservoir

Gilboa Dam Rehab Update

Rehabilitation of Gilboa Dam is Two Years Ahead of Schedule. For more information, read the DEP Press Release

NYC DEP presented a Gilboa Dam Reconstruction project update at the DCC annual meeting of April 9, 2013. Special thank you to NYC DEP for the update and the Power Point presentation.


4/9/13 Via DCC, Inc.'s 6th Annual Meeting

NYCDEP presentation on Hurricane Irene flood damage to Gilboa Dam and Dam work site/flood recovery and rehabilitation update.

NYCDEP Power Point Presentation - NYCDEP presented an enlightening power point program at DCC, Inc.'s 6th Annual Meeting, 4/12/2012. Of interest to the public were the damages sustained the Gilboa Dam during the Hurricane Irene induced Flood of Aug. 8, 2011. Photos showing the power of the water were amazing and the damages have been repaired. Also included are rehabilitation updates on present and future repairs. DCC, Inc. wishes to thank NYCDEP for this fine presentation. Also, we would like to thank Michael Quinn, Geotechnical Engineer of ARCADIS for his excellent presentation on "Dam Safety".

Preview: NYCDEP Power Point A then NYCDEP Power Point B both are in .pdf format.


9/8/10 Via phone call with John Vickers-Chief of Operations

This report is not a NYCDEP published, documented report. It is a summary of a phone conversation between DCC, Inc. and Chief of Operations at the Gilboa Dam. Report prepared by S. Bartholomew, DCC, Inc. President. View Gilboa Dam Rehab Update .pdf

The latest "Project Updates Briefing" is available on NYCDEP Project Information page.


1. Gates: began in May full force

    a. Install fall protection for workers

    b. Placed anchors in notch

    c. Poured concrete in anchor channels

    d. Excavated for air lines for bladders

    e. Piping is in place-everything stainless steel

    f. These are to be encased in concrete

    g. Separate airlines for each bladder

    h. 11 gates-20 long with 2 bladders for each gate

    i. low pressure of 140 lbs/sq inch

    j. one extra gate and 2 extra bladders on site for replacement if something happens.

2. Control unit

    a. Foundation has been poured for temporary control building on western abutment

    b. Upper gate chamber rehabilitation is proceeding

    c. Permanent controls will be installed in upper gate chamber/western side parapit

    d. Old low level valves will be filled in with concrete-no threat to safety

3. operation of gates from grahamsville?

    a. Manned 24/7

    b. Not 24/7 from Gilboa-not a resident engineer on 24 hours

    c. Operators are trained for multiple emergencies

        i. Earthquakes

        ii. Floods

        iii. Alarm redundancy

        iv. Position elevations at dam, etc.

    d. Immediate call to Gilboa police station to engage emergency

    e. Can correct some things from there

    f. Camera installed to monitor gates only

    g. Lots of early warning and instrumentation installed in gates

    h. Stand by generator

    i. Air lines still function with out electricity for a period of time. Low pressure

4. siphons:

    a. in place until winter of 2011/2012

    b. contractor controls when they are to be removed

    c. it should be a 2 year window of no siphons or LLO

    d. Intake chamber can handle siphon output providing ashokan is not full

    e. Not able to meet snow pack management plan not a problem because it was an agreement not a requirement

    f. Suggested pumps and they feel that the size would have to be too large, no place for them on dam spillway surface

5. Union college sensors-

    a. Sensor buried on left side of 990 V bridge due to moving of stilling pool which had to be move to install piers for bridge

    b. Sensor seems to be buried

6. Bridge is coming along

7. Stilling pool was moved

8. Low Level Outlet:

    a. Did make trip to utah

    b. Redesigned llo valve bldg. Hood 80 X 210

    c. Energy dissipation will take place inside bldg.

    d. Water will slide down slide to creek below creek bank where there were concerns about erosion.

    e. Provision in design of Y upstream of hood to put in generator for hydro

    f. Working on math model that will take in account condition of snow pack and info provided by NWS to make better decisions concerning water draw down for snow pack mp

    g. It is a 3 year study.

    h. Basing information on kensico reservoir study. Called an operation support tool

9. Western Access road almost completed

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