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Thursday, February 5, 2015

Coordinated by:

Briefing on:

DC CLEAN RIVERS PROJECT

First Street Tunnel

Chairperson James A. Turner

District of Columbia Water and Sewer AuthorityGeorge S. Hawkins, General Manager

Briefing for the:

Residents of

Presented by:

John Kennedy and Tom Lindberg, DC Clean Rivers Project

Emanuel Briggs, DC Water


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Agenda

Separate and combined sewer systems explained

Why Combined Sewer Overflows (CSOs) are a concern

Long Term Control Plan (DC Clean Rivers Project)

13-mile tunnel system and structures Northeast Boundary Tunnel facts, figures, and alignment

First Street Tunnel facts and figures

Status of construction

Truck routes Tunnel Boring Machine delivery schedule

Contact information and Questions & Answers

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Combined Sewer Overflows (CSOs)

Combined sewer overflows contaminatereceiving waters

Primary concerns:

Elevated bacteria levels

Low dissolved oxygen in water Potential for fish stress or fish deaths

Negative effects on other aquatic life

Aesthetics: contributes to trash inwaterways

Limit fishable conditions

Contribute nutrients and sediments thatnegatively affect the Chesapeake Bay

CSO 017 to Anacostia River (during Hurricane Floyd)

CSO 017 during dry weather conditions

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DC Clean Rivers Project(DC Waters Long Term Control Plan)

To comply with the U.S. Environmental Protection Agencys (EPA)

Combined Sewer Overflow (CSO) Control Policy, DC Water is

implementing a schedule

for numerous projects

to control combinedsewer overflows into:

Anacostia River

Potomac River

Rock Creek

2002

DC Water completed a Long Term Control

Plan (LTCP)

2005

DC Water entered into a consent decree

agreement with EPA and DC government

2011 DC Clean Rivers Project Execution

2025

Projected DC Clean Rivers ProjectCompletion

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Tunnel System

AnacostiaRiver

Potomac

River

DC WaterBlue PlainsAWWTP

U.S.CapitolBuilding

NE BoundaryTunnel & area

projectsAug 2016

Sept 2025

NE BoundaryTunnel & area

projectsAug 2016

Sept 2025

First StreetTunnel

Oct 2013 Mar 2016

First StreetTunnel

Oct 2013 Mar 2016

Mine four large storage/conveyancetunnels, totaling 13 miles

Construct a tunnel dewatering pumpingstation at Blue Plains

Replace pumping station at Poplar Point

Construct M Street Diversion Sewer

Build two tunnel overflow structures

Project schedule:

Tunnels south of Robert F. Kennedy (RFK)

Stadiumoperational by 2018 Northeast Boundary Tunneloperational by 2022

Anacostia River water quality will be

greatly enhanced by reducing CSOs

from 82 to 2 events per year by

capturing 98% of CSOs

N

RFKStadium

Joint BaseAnacostia-Bolling

Blue PlainsTunnel

Sept 2011 Nov 2015

Blue PlainsTunnel

Sept 2011 Nov 2015

AnacostiaRiver Tunnel

Nov 2013 Aug 2017

AnacostiaRiver Tunnel

Nov 2013 Aug 2017

M StreetDiversion Sewer

May 2012Dec 2014

Poplar PointPumping Station

Dec 2014 Mar 2017

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Northeast Boundary TunnelAt a Glance

Major component of DC Waters DC Clean Rivers Project, required under

a Federal Consent Decree

Increase the capacity of the existing sewer system in the District,

significantly mitigating sewer flooding and improving the water quality of

the Anacostia River

Approximately 27,000 feet long, 23 feet in diameter, and between 80 to

160 feet below ground

Diversion facilities will be constructed near chronic flood areas along the

tunnel alignment to relieve the existing sewer system

Ventilation control facilities will also be constructed

Captured flows will be delivered to Blue Plains for treatment prior to

discharge to the Potomac River

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Northeast Boundary Tunnel Alignmentand Chronic Flood Areas

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First Street TunnelAt a Glance

Constructed to mitigate sewerflooding and basement backups inBloomingdale and LeDroit Park

Provides 8 million gallons of storage

2,700 feet long, with four shafts Mined from Channing Street NW to

Rhode Island Avenue NW using aTunnel Boring Machine (TBM)

70 to 120 feet below the ground

23-foot inner diameter tunnel Five Construction Staging Areas

Temporary below-ground pumpingstation

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TBM Mobilizationand Assembly

TBM parts havestarted to arriveon site

CS-MS Base Slaband Permanent Liner

Poured base slab

Poured permanentliner lift 1

First Street Diversion Chamber

Drilled secant and soldier piles

V StreetDropShaft and AditFreeze System

Completedinstallation of pipes

Started freeze formation at drop shaft

Pump StationDrop Shaft and Adit

Completedinstallation of pipes

Started freeze for-mation at drop shaft

Drill and installfreeze pipe at adit

Poured drop shaftcollar

Adams Street

Drop Shaft Drill and install

freeze pipesunderway

Adams Street

A/FST Connection Drill and install

freeze pipesunderway

First Street Tunnel isApproximately 37 Percent Complete

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Delivery ofTunnel Boring Machine Sections

The First Street Project Tunnel Boring Machine(TBM) was recently refurbished in Germany

The TBM is being delivered in sections to theChanning Street Construction Staging Area over

the next two weeks

Delivery will temporarily restrict access to theMcMillan Reservoir entrance on First Street

There will be a few days when certain sections

will require offloading using a large crane

On days of offloading, the crane will be inFirst Street travel lanes

TBM assembled in Germany

TBM being prepared for assembly

at the Channing StreetConstruction Staging Area

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The TBM will be delivered insections to the Channing Street

Construction Staging Area using

Irving Street, Michigan Avenue,

and North Capitol Street

Oversized loads will have policedetail

No additional street closings will

be required

No additional on-street parking

will be affected

N

Channing St

CSA

FirstStNW

Truck Routes

Legend

Truck traffic leaving site

In-bound truck traffic

Channing Street CSA

Flagger as needed12


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Tunnel Boring MachineDelivery Schedule

The first of the deliveries began onWednesday, January 28

The second delivery arrived on Monday,

February 2

The next delivery is tentatively scheduledfor Thursday, February 5

Final delivery of TBM equipment will be

during the week of February 9

The First Street Tunnel project will becompleted in the Spring of 2016

Thank you for your patienceand understanding

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TBM midshield bottom section


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Contacts

Tom LindbergPublic Outreach ManagerFirst Street TunnelDCCleanRiversProject,DCWater

Email: [email protected]: 202-787-4478

Emanuel BriggsManager, Community Outreach

External Affairs, DC WaterEmail: [email protected]: 202-787-2003

dc water divp_tunnel_forum_pres_anc 1b-final 2015 02 05

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