GILBOA DAM

RECONSTRUCTION PROJECT

UPDATE

Dam Concerned Citizens

Public Meeting

April 9, 2013

2

GILBOA DAM RECONSTRUCTION PROJECT

Presentation Agenda

Project Overview and Schedule Update

Reconstruction Progress

Actions Moving Forward

Questions / Discussion

3 3 3

Gilboa Dam:

Planned reconstruction work is

intended to repair long-term

deterioration, upgrade the dam to

current standards, and improve the

operational capability. The main work

at the dam will be completed in 5

Phases.

1) Installation of 80 post-tensioned anchors

(CAT-275 – completed Nov 2006).

2) Installation of spillway crest gates (CAT-359

– completed June 2012).

3) Site work (CAT-212A – completed March

2011).

3) Reconstruction of the dam (CAT-212B –

est. completion 2014). Installation of a low-

level outlet (CAT-212C – est. completion

2019).

4) Rehabilitation of Shandaken Tunnel Intake

Chamber (CAT-212D – est. completion

2018).

5) Site Restoration (CAT-212E – est. 2022)

Gilboa Dam (circa 1927)

Gilboa Dam (today)

PROJECT OVERVIEW

4

PROJECT OVERVIEW

Major Scope Items for Phases 1, 2, 3A

5

PROJECT OVERVIEW

Conceptual Plan of Low Level Outlet (Phase 3B)

6

PROJECT OVERVIEW

Current Project Schedule Interim Construction

(Debris Barrier, Siphons,

Notch, Anchors)

Preliminary Design

Release Environmental Document

Final Design

Final Rehab. Construction

Phase 1 - Crest Gates

Phase 2 - Site Preparation

Phase 3A - Dam Reconstruction

Phase 3B - Low Level Outlet Installation

Phase 4 - Shandaken Intake

Phase 5 - Restoration

2006 2007 2008 2009 2010 2011 2012

Interim Construction

(Debris Barrier, Siphons,

Notch, Anchors)

Preliminary Design

Release Environmental Document

Final Design

Final Rehab. Construction

Phase 1 - Crest Gates

Phase 2 - Site Preparation

Phase 3A - Dam Reconstruction

Phase 3B - Low Level Outlet Installation

Phase 4 - Shandaken Intake

Phase 5 - Restoration

2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

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CONTRACT WORK UPDATE

Spillway Control Section looking west

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CONTRACT WORK UPDATE

Spillway Channel Slabs

9

CONTRACT WORK UPDATE

Anchors and Reinforcing for Spillway Slab

10

CONTRACT WORK UPDATE

Repointed Masonry at North Training Wall

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CONTRACT WORK UPDATE

Installing Post-Tensioned Anchors

at West Training Wall

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CONTRACT WORK UPDATE

Installing Post-Tensioned Anchors

at West Training Wall

13

CONTRACT WORK UPDATE

East Temporary Siphon Being Installed

14

CONTRACT WORK UPDATE

Both Temporary Siphons Discharging into Plunge Pool

15

Winter construction work was generally limited to anchor installation,

electrical systems and work within the upper and lower chambers

Concrete work is more weather sensitive and will be resumed as

conditions allow - most work activities will resume in April and May

DEP is progressing on the NYSDEC permit requirement to study the

potential for a conservation release – report due NLT December 31, 2014

DEP continues to meet its snowpack offset agreement and has

completed the construction of two temporary siphons to ensure continued

reservoir operations until the new Low Level Outlet is completed

ACTIONS MOVING FORWARD

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QUESTION / DISCUSSION

QUESTIONS?