Los Angeles County Metropolitan Transportation Authority Westside Subway Extension Community Update Meeting August 2009
Purpose of Tonight’s Meeting • Summary of Comments from Public Scoping • Update on Alternatives • Construction Overview
Westside Subway Extension Study Area
Alignments Presented During Environmental Scoping Wilshire Subway Wilshire/West Hollywood Subway
Other Alternatives Required for Further Study • No Build – Service improvements to existing Metro Red/Purple Lines by 2035 – Assumes new rail lines with Measure R funding identified through 2035 � Exposition LRT Phase 2, Crenshaw, Regional Connector, etc. • Transportation Systems Management (TSM) – Lower-cost improvements to maximize efficiency of existing road & transit networks
Possible Schedule for EIS/EIR & Beyond Min. 6 Years to ? * 0 18 21 33 Months Months Final Design Draft EIS/EIR Final EIS/EIR/PE Construction * • Metro Board • Metro Board • Federal Selects LPA Approved Alternatives Record of Analysis Study Decision (Certification) • Federal Approval for • Full Funding Preliminary Grant Engineering Agreement (PE) * Depends on Funding Availability
Summary of Input Received During Public Scoping
Draft EIS/EIR Scoping Comments • 6 Public Scoping meetings • 342 people attended • 91 speakers • 30 handed in written comments • 135 comments sent in
Most Heard Scoping Comments • Overwhelming support for subway • Accelerate schedule & lengthen initial segment(s) of subway • Connect with existing & future rail
Most Heard Scoping Comments (Cont’d) • Construction impacts & potential mitigations • Tunneling under private property • Station area parking • Station-specific comments (e.g. Crenshaw, West LA) • Traffic impacts
Update on Alternatives
Refinement of Build Alternatives Since Scoping Initial focus: Narrow options for each station location Next steps: Further refine stations & alignments
Build Alternative: Wilshire Subway
Build Alternative: Wilshire/West Hollywood Subway
Century City Station • 3 station options identified – Santa Monica Boulevard – Constellation Boulevard – Avenue of the Stars • Avenue of the Stars eliminated – Alignment under golf course – Longer route, more travel time & higher cost – Under many private properties • Continue to study – Santa Monica Boulevard – Constellation Boulevard – Alignments
Westwood Station • 4 station options identified – Le Conte – Westwood (N/S) – Wilshire/Westwood (on-street) – Wilshire/UCLA (off-street) • Le Conte & Westwood (N/S) eliminated – require alignment under cemetery – greater construction impacts in Westwood Village • Continue to study 2 Wilshire Boulevard station options & alignments
West Los Angeles Station (i.e. West of I-405) • Additional 1-2 stations needed between Westwood & Bundy • 4 Station options identified: – Veterans Administration (VA) Hospital – Federal – Barrington – Bundy • Federal eliminated – Close to Barrington – Impact on sensitive property • Continuing Study of interim terminus (MOS 3): – VA Hospital • Serves important destination • Park & ride possibility • Possible off-street construction – Barrington • High boardings projected • Bundy – Too far west for MOS 3 – Potentially part of further westward subway extension
West Hollywood Alignment • San Vicente Boulevard alignment selected over La Cienega Boulevard – Allows a station west of La Cienega – Better located in commercial & activity center of West Hollywood • Will also continue to evaluate possible transfer station at Wilshire/La Cienega
Metro is Now Further Refining Build Alternatives • Decisions about stations – Optional Crenshaw station – Alternative locations at: � Westwood, Century City, West LA & Wilshire/La Cienega – Location-specific details � Station entrance(s), station urban design, parking & engineering Metro Purple Line: Wilshire/Western Station • Decisions about alignments – Identify best possible alignments – Define alignment details Metro riders boarding Red Line
Identify Locally Preferred Alternative (LPA) • LPA: Project identified to be environmentally cleared through the Final EIS/EIR • Must be both: – Eligible & highly competitive for federal “new starts” funding – Able to be built & operated within projected available funding • Also incorporates decisions about Minimum Operable Segments (MOS) Measure R Expenditure Plan Measure R Expenditure Plan identifies $4.1 billion for the identifies $4.1 billion for the Westside Subway Extension Westside Subway Extension over 30 years over 30 years
Metro Soils Investigation Currently Underway • Conducting geotechnical testing & gathering soil samples at about 70 locations throughout study area Drill rig along Wilshire Boulevard
Construction Overview
Identifying Construction Impacts • During Draft EIS/EIR – Identify how project will be constructed and its impacts • Tunnel & station construction processes • Construction staging & soil removal locations • Materials hauling routes & other traffic considerations • Air, noise, vibration & other impacts • Possible mitigations • During Final EIS/EIR – Adopt construction mitigation plan • Factors in making construction decisions – Engineering/Technical – Cost – Timing – Community Input
How a Subway is Constructed • Tunnels – Use tunnel boring machines (TBMs) • Stations – Excavated under “decked-over” streets or off-street Twin Tunnels on Eastside Extension
21 st Century Subway Tunneling • New generation TBMs maintain pressure in surrounding earth • Reduces risk of settlement • “It is possible to tunnel and operate a subway along the Wilshire Corridor safely” (APTA Peer Review, 2005) TBM maintains pressure in surrounding earth as it tunnels
Recent Metro Tunneling Experience Gold Line Eastside Extension: • 1.8 mile tunnel segment • 2 underground subway stations • No measurable surface subsidence Gold Line Eastside Extension Tunnel • No substantiated property damage claims • Excellent safety record • Used pressurized face TBMs Soto Street Station Under Construction
Typical Steps for Tunneling 1. Prepare site & excavate shaft where TBMs lowered into ground 2. Lower TBMs using cranes 3. Excavate two parallel tunnels (22 ft. diameter) 4. Install precast, gasket-lined, concrete tunnel lining 5. Install rails, electrical & other systems Cross-section of tunnel lining 6. Remove excavated soil at shaft Boring can proceed on each tunnel simultaneously Boring can proceed on each tunnel simultaneously Machines excavate about 50 feet per day Machines excavate about 50 feet per day
Typical On-Street Station Construction Process 1. Relocate utilities as necessary to maintain service 2. Drill “soldier piles” on station box perimeter at edge of roadway 3. Remove top 12’ of soil below Street Excavation existing roadway 4. Install concrete decking in roadway Decking is flush with existing street level so Decking is flush with existing street level so traffic continues to flow traffic continues to flow Concrete Decking
Typical On-Street Construction Process (Cont’d) 5. Install shoring & excavate area beneath deck to depth of station 6. Construct station box in excavated area 7. Install station elements/ architectural features 8. Remove decking, repave street & re-open to traffic Construction below ground while traffic continues to flow above
Typical Off-Street Station Construction Process 1. Drill “soldier piles” on station box perimeter 2. Excavate station box 3. Construct station box in excavated area Wood beams installed between soldier piles 4. Install station elements & architectural features 5. Cover station box & restore area Off-street station box excavation
Typical Station Construction Timing • 2-5 Months* – Drill soldier piles along roadway or around station site – Install decking • 45 Months – Excavate & support station area – Construct cast-in-place concrete station & add station elements • 2-4 Months* – Remove decking & restore street *Most disruptive activities to local community for on-street stations Total = 48-54 Months Typical Cross Section Station box 600’ long x 60’ wide x 60’ deep (approx.)
Construction in Gassy Areas • Pressure face TBMs isolate gas from workers & public • Gassy soil & tar sands separated and treated appropriately • Enhanced ventilation system ensures tunnel & station safety • Double gaskets for tunnel Soil slurry contains excavated soil in pipe thru tunnel. lining or other methods Gassy soil & tar sands separated & treated as necessary. as appropriate
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