Rock Creek Sewer Separation & Water Main Replacement – CSO 031, 037, 053 and 058 Presented to...

Rock Creek Sewer Separation & Water Main Replacement – CSO 031, 037, 053

and 058Presented to

CWEA / WWOA / CSAWWA

2011 Tri-Association Conference

Collections Systems

August 31, 2011

Wednesday – 1:30pm

District of Columbia

Water and Sewer Authority

CSO LTCP – Consent DecreeDEADLINES!!!

Award Design Contract

March 23, 2007

Award Construction Contract

March 23, 2009

Complete SeparationMarch 23, 2011

2

CD Project RequirementsDC Water needs

to separate the areas tributary to CSOs 031, 037, 053 and 058 in order to eliminate them as CSO outfalls. 3• Foggy Bottom

• DuPont• Circle• Georgetown

• National• Zoo

• Woodley• Park

• CSO 031

• CSO 037

• CSO 053

PROJECT LOCATIONS

• CSO 058

4

CSO 031 - Overview Smallest sewershed to

separate – approx 2 acres

Comprises one building (mixed use)

Work located south of Pennsylvania Ave, NW on NPS property

Requires 160 ft of 10” sanitary sewer installation

M Street

Pennsylvania Avenue

26th Street

Rock

Cre

ek &

Pot

omac

Par

kway

L Street

5

CSO 037 - Overview Sewershed approx 15

acres 57 Private Properties

(Residential / Embassy) In DDOT (Public) ROW:

3500 ± feet of new sewers (san & storm)

3600 ± feet of water main replacement

1800 ± feet of sewer rehabilitation (san)

NPS Property: 600 ± feet of

sewers installed via trenchless methods

Rock Creek & Potomac Parkway

Massachusetts Avenue

24th Street

Kaloram

a Road

6

CSO 053 - Overview Sewershed approx 10

acres 10 Buildings in Project

Site (6 res., 4 large multi-unit)

In DDOT (Public) ROW: 675 ± feet of new

sewers (san & storm)

875 ± feet of water main replacement

NPS Property: 825 ± feet of new

sewers (Portions installed via trenchless methods)

Q Street

Rock Creek & Potomac Parkway

P Street

7

CSO 058 - Overview• Approx 22 acres remaining to

separate in the sewershed (DC PWD separated the other 83 acres in the 1960’s)• Approx 30 Buildings in Project Site (Residential / Commercial)• Public ROW:• 1000 ± feet of sewer

installation (san & storm)• 1200 ± feet of sewer rehabilitation (sanitary)• 2000 ± feet of water main replacement• NPS Property:

• 1100 ± feet of sewer installation (250 ± feet via trenchless methods)

Calvert Street

Rock Cree

k & Potomac

Parkway

Connecticut Avenue

Separation Planning Challenges Major Traffic Routes Affected Environmental Assessment

Required DC Water has NO easements on

Federal (NPS) and District property Voluntary private property

separation Embassies required State

Department Involvement 8

Separation Design ChallengesAvoid / Minimize Disturbances to –

bridges, historical sites,major traffic routes,building driveways &

access, NPS property,

existing utilities, Metro

stops, embassy events...

9

Project StatisticsEngineer’s Estimate -

$13,166,273.00Contract bid value -

$10,992,563.00Anticipated Completion Cost -

$12,000,000.00Notice to Proceed - Mar. 25,

2009Contract Milestone - Jan. 24, 2011EPA Consent Decree Date - Mar. 23,

2011(Sewer Separation Complete)

Project Completion Date - Nov. 20, 2011

StakeholdersU.S. State Department

Embassies/ConsulatesNational Park ServiceDDOTMosqueResidentsBusiness

Owners/RestaurantsApartments/Senior

HousingANC’s/Ward

Friends of Rock Creek (FORC)

DDOE (now an MS4 area)

PermitsDistrict (Dept. of Consumer Regulatory Affairs

– DCRA)Public Space PermitsTraffic Control & After Hours (DDOT)Stormwater Mgmt / S & E Control (DDOE)

Federal (National Park Service – NPS)Environmental Assessment

Archaelogical / Historical Wetland / Floodplain Etc.

Special Use PermitOthers

Major Construction IssuesKalorama Road

Electric duct conflictBelmont Road

NPS land – Unanticipated rock

Kalorama Road – Storm SewerElectric Duct Bank – 350 foot

conflictLimited space for rerouting due to

other utilitiesLimited corridors for relocating due

to major electric crossing/vaultTime constraintsCost Issues

Kalorama Road

Kalorama RoadView of Electric Vault

Kalorama RoadView of Tunneling Shield

Kalorama RoadTunnel Face with Rock

Kalorama RoadHand Mining

Kalorama RoadFrom Tunnel Looking South

Belmont Road/NPS - RockTime to complete first boreAdditional 2 bores with rock at

launch pitSteep slopesNPS land subject to no surface

disturbanceLocating rock surface profileDetermining proper equipmentTime constraintsSuccessful Bores

Proposed Seismic Alignment

Velocity Profile

Proposed Vertical Alignment

Belmont RoadLooking Uphill (South)

Belmont RoadEquipment Setup

Belmont RoadEquipment Setup

Belmont RoadEquipment Setup

Belmont RoadTunneling

Belmont RoadTunneling

Belmont RoadTunnel Face

Lessons Learned Start Early!Take care of all the stakeholdersAdditional upfront utility locatesSubsurface ExplorationPartnering with ContractorFlexibility in Construction