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Caldecott Tunnel Corridor Study

Executive Summary

The Metropolitan Transportation Commission with its partners–Caltrans, the Alameda County Congestion Management Agency, and the Contra Costa Transportation Authority–began the Route 24/Caldecott Tunnel Corridor Study in June 1999. The Study’s intent was to:

  • Address improvements along the entire Route 24 Corridor between I-680 in Contra Costa County to I-580 in Alameda County
  • Evaluate a full range of transportation options including improvements to transit, carpooling, freight movement, non-motorized options, and a new bore–specifically analyzing project performance, impacts, and costs
  • Inform decision-makers on the most promising Corridor investments
  • Identify funding options for proposed Corridor investment strategies

MTC Commissioners Mark DeSaulnier and Mary King co-chaired a 14-member Policy Advisory Committee (PAC) to help guide the Study. Early on, the PAC agreed that the Study should find ways to move people, not vehicles, through the Route 24 corridor; improve mobility, travel times, reliability/convenience for travelers; protect local streets from impacts; and address environmental, economic and growth issues. In addition to the PAC, a Technical Advisory Committee (TAC), which consisted of staff from agencies within the corridor and included representatives of environmental, neighborhood, and other interested groups, provided technical oversight to the Study.

What are the Existing Transportation Conditions?

Route 24 serves as a major transportation corridor between Alameda County and Contra Costa County, particularly for commuters traveling from their homes to workplaces in Central Contra Costa County, Alameda County, and San Francisco. Existing travel can be characterized as follows:

  • Most of the vehicle trips through the Tunnel during peak period peak commute direction are between Oakland/Emeryville and Concord/Pleasant Hill/Walnut Creek.
  • While traffic volumes are higher in the peak commute direction (westbound A.M, eastbound P.M.), the volume of trips in the off-peak or "reverse" commute direction (eastbound AM, westbound PM) is increasing at a higher rate.
  • When compared to other corridors, Route 24 has a relatively large transit share with about 33% taking BART during the westbound morning commute and almost 14% during the eastbound morning commute.
  • Carpools and vanpools, however, comprise a relatively small percentage of the vehicles on Route 24 during commute periods (less than 10%, compared to over 15% regionwide).
  • Tunnel queues can impede traffic entering the freeway from local on-ramps and Route 13. For example, for eastbound Route 24 during the morning commute, queues typically extend about 0.5 miles from the west tunnel portal, just beyond the Route 13 on-ramp. Similarly, queues at the westbound approach to the Caldecott Tunnel during the morning and evening commutes extend upstream of Orinda’s Camino Pablo/Moraga Way interchange.

What Strategies Did We Consider?

Over the last year, we have analyzed the existing transportation conditions in the study corridor and considered several transportation strategies.Three Transportation Packages

Streets and Highway Operations: meter on-ramps in the reverse commute direction, relocate merges near both sides of the Tunnel, and install High Occupancy Vehicle (HOV or carpool) lane "queue jumpers" in both directions during morning and evening peak periods (using westbound auxiliary lane between Orinda and Tunnel, using freeway median shoulders, or using movable barriers to capture unused reverse commute capacity)

Transit (Bus and BART Expansion): increase feeder bus to/from BART during morning and evening peak periods for both directions, establish new inter-county bus service through the Tunnel during morning and evening peak periods in both directions, provide direct Bay Point/Fremont BART service, and expand corridor BART station parking

New 4th Bore: construct a new 2-lane or 3-lane bore at the Caldecott Tunnel

Land Use and Pricing Sensitivity Analysis

Additionally, we performed a land use and pricing sensitivity analyses on the transportation packages to assess impacts on forecasted corridor travel behavior. The land use sensitivity analysis increased Association of Bay Area Governments’ (ABAG) 20-year population and employment forecasts in the region’s urban cores, and decreased forecasts in the region’s suburban and rural areas. The pricing sensitivity analysis evaluates how various pricing strategies would increase auto trip costs or reduce transit costs as follows:

  • Tolls to pay for new 4th bore
  • Tolls to manage demand (High-Occupancy Toll Lanes -- HOT Lanes)
  • BART parking charges and fare reductions in off-peak
  • Reduced BART feeder bus fares

What Are The Major Findings?

Our evaluation of the strategies–three transportation packages, tolls and pricing, and land use–indicate:

  • Lower-cost freeway improvements would provide minor corridor congestion relief; however, carpool (or High Occupancy Vehicle–HOV) lanes could be installed cost-effectively by using one of the two unused freeway lanes in the reverse commute direction.
  • Several major employers on both sides of the Tunnel are already well connected to corridor transit services. Our analysis showed that a vastly improved feeder bus service to BART and new inter-county express bus service would provide modest congestion relief for travel in the corridor but only minor congestion relief through the Tunnel; however, expanded feeder and express bus service could benefit key employment and residential locations within the corridor.
  • Adding a new BART route from Pittsburg/Bay Point to Fremont did not significantly increase transit use through the Tunnel and would be costly to operate in terms of new vehicles and operating subsidies.
  • BART parking demand throughout corridor far exceeds existing capacity. Additional parking at or near by BART stations throughout the corridor (from MacArthur BART to Pittsburg/Bay Point BART) is needed to address existing and future shortfalls in parking.
  • A new 2-lane bore located north of the existing tunnel would eliminate eastbound A.M. and westbound P.M. weekday tunnel congestion, and would also eliminate weekend congestion through the year 2020 planning horizon; it would not affect westbound A.M. and eastbound P.M. tunnel congestion.
  • A new northerly 2-lane bore with a third auxiliary lane (between Orinda and Route 13) would move the westbound A.M. queue through the Tunnel and merge with the Route 24/980/580 queue, and therefore would not significantly reduce westbound morning congestion.
  • Existing traffic volumes are creating operations problems on streets in adjoining neighborhoods, which may be exacerbated by the expected growth in traffic generally. A new bore, which would increase capacity in the reverse commute direction, would not deliver any greater traffic to local streets than generated in the peak direction.
  • A preliminary assessment indicates that a new 4th Bore would likely not create significant environmental impacts that could not be mitigated; a full analysis of impacts (e.g., noise, local traffic) and determination of necessary mitigations is desirable and would be required as part of the formal environmental process.
  • Providing bike access through a new bore would be very costly, and there are more cost-effective ways to improve bike travel between both sides of the tunnel.
  • Corridor growth and development is heavily influenced by regional and national economic conditions, local land use and development policies, and improvements elsewhere in the regional transportation network.
  • None of the improvements considered appear to have adverse impacts on any low-income or minority communities, a consideration to be further addressed in federal metropolitan planning regulations and as part of the formal environmental process.

Corridor Improvement Strategy

A corridor improvement strategy was developed based on the study findings discussed above. A broad range of improvement strategies that could be implemented in either the short-term (with full implementation within a one- to four-year timeframe) or long-term (with full implementation after four or more years) was developed. In addition, most of the long-term projects will require a substantial funding commitment from federal, state and regional sources, and require extensive lead-time to complete environmental review and project design.

In summary, the short-term strategy includes:

  • Tunnel operations — tunnel tiling, HOV queue jumpers, fixed weekend center bore switch time demonstration
  • Related traffic and roadway improvements — Route 13/24 auxiliary lane, local traffic studies
  • BART and transit improvements — increased BART feeder bus, new corridor express bus, increased satellite BART parking
  • 4th Bore environmental study — this study concluded a new 2-lane north bore that would provide 4 lanes in both directions would be the most cost-effective tunnel option
  • Assess short-term bicycle/pedestrian tunnel access options

Long-term strategies include:

  • Additional parking and transit interface at BART stations that incorporate transit-oriented development
  • Expanded corridor feeder and express bus service beyond short-term improvements
  • Construct 4th Bore
  • Provide long-term bicycle/pedestrian access
 

Recommended Corridor Improvement Strategy

CORRIDOR SHORT-TERM STRATEGIES (1 TO 4 YEARS)

Funding Status

I.D.

#

Project

Cost

(2000/2001 $)

Identified or Possible Fund Sources

Lead Agency

Full Funding Expected

(1)

Tile Tunnel Bores 1 & 2

$10 million

SHOPP

Caltrans

(2)

Local Circulation/ Traffic Calming Studies (i.e., Rockridge, Tunnel Road, and Lamorinda neighborhoods)

$40,000

TETAP

MTC, Cities

(3)

Carpool lane Reverse commute direction (eastbound A.M. and westbound PM) Queue Jumpers

$100,000

RTIP or SHOPP

Caltrans,

ACCMA

(4)

Route 24: Brookwood eastbound (Camino Pablo) off-ramp

$1.1 million

RTIP, Measure C

Caltrans,

CCTA, Orinda

(5)

Carpool to BART Program Enhancement (i.e., Lafayette, other stations)

Ongoing

BART

BART

(6)

Extended Evening Hours for Moraga Way Shuttle Service to Satellite BART Parking (Moraga Park & Ride to Orinda BART)

$27,000

TFCA

Moraga, CCCTA

(7)

Assess Low-Cost/Short-Term bicycle/pedestrian access options

Study

Caltrans, RTIP

Caltrans

(8)

Fixed Weekend Center Bore Switch Times

N/A

N/A

Caltrans

(9)

4th Bore Environmental Analysis (e.g., noise, local traffic impacts)/Final Design

$25 million

TCRP (bore)

Caltrans

           

Partial Funding Identified

(10)

Extended Moraga Way Shuttle Service to Satellite BART Parking with Stops in Orinda (A.M. and P.M. Peak and extended P.M. Hours)

$94,000

BART

Orinda, BART, CCCTA

(11)

Regional Express Bus Service

TBD

TCRP (bus), local, private

AC, CCCTA, MTC

(12)

BART Access Policy (will assess off-site and on-site parking and bus shuttle, and vehicle, bicycle and pedestrian access improvements)

TBD

BART

BART

 

 

CORRIDOR SHORT-TERM STRATEGIES (1 TO 4 YEARS) (continued)

 

 

Funding Status

 

I.D.

#

 

Project

 

Cost

(2000/2001 $)

Identified or Possible Fund Sources

 

Lead Agency

No Funding Identified

(13)

Feeder/Shuttle Bus Service — enhancements (e.g., reduced headways) and expanded service to be identified by local transit operators

TBD

TIP, RTIP, TFCA, local,

private

AC, CCCTA

(14)

Northbound Route 13 Auxiliary Lane between Broadway Terrace on-ramp and Route 24 eastbound on-ramp

$3 million

RTIP, SHOPP

Caltrans, ACCMA

(15)

Support BART transit village development in corridor (e.g., Walnut Creek, MacArthur, and other corridor stations where feasible)

TBD

TLC, local, private

BART, Cities

(16)

Satellite BART Parking with Shuttle Service to BART/Park & Rides where feasible and practical (e.g., Oakwood Health Club, Lafayette, Moraga, Orinda)

TBD

TIP, RTIP, local, private

BART, Cities

(17)

Rockridge area soundwalls pursuant to ACCMA Soundwall Policy

TBD

RTIP

ACCMA, City

CORRIDOR LONG-TERM STRATEGIES (4+ YEARS)

Funding Status

 

I.D.

#

 

Project

 

Cost

(2000/2001 $)

Identified or Possible Fund Sources

 

Lead Agency

Partial Funding Identified

(18)

Construct 4th Bore of Caldecott Tunnel

$160 million for 2-lane bore*

TCRP (bore), ITIP, Bridge Tolls, Sales Tax

Caltrans

(19)

Route 24: Gateway to Brookwood (Camino Pablo) Eastbound Auxiliary Lane

$10.3 million

RTIP/Measure C

Caltrans, CCTA, Orinda

           

No Funding Identified

(20)

Additional corridor BART Parking

TBD

RTIP, Sales Tax

BART, CCTA, ACCMA

(21)

Expanded Feeder & Shuttle Bus

TBD

TIP, RTIP, local, private

AC, CCCTA

(22)

Expanded Express Bus Service

TBD

TIP, RTIP, local, private

AC, CCCTA

(23)

Provide long-term bicycle & pedestrian access

TBD

TIP, RTIP, local

CMAs, Caltrans

(24)

Route 24: Pleasant Hill Rd to Deer Hill Road Westbound Auxiliary Lane

TBD

TIP, RTIP, local

Caltrans, CCTA, Lafayette

* Construction cost only; total estimated cost is $185 million (includes funded $25 million for environmental and design) for a standard 2-lane bore. 4th Bore costs range from $152 million to $401 million, depending on shoulder width, number of lanes or bike path inclusion.

 

Fund Source Abbreviations

 

Fund Source

Description

Bridge Tolls

New bridge tolls — would require local/state approval

ITIP

Interregional Transportation Improvement Program — state highway funds available for state highways and rail projects programmed by the state — Caltrans is requesting $10 million in upcoming programming cycle for environmental analysis and preliminary engineering

Local

Includes, but not limited to: city/county road/general funds, transit agency funds, Transportation Fund for Clean Air (TFCA - air district funds)

Measure C

Contra Costa County’s existing transportation sales tax (expires 2008)

RTIP

Regional Transportation Improvement Program — state highway funds available to counties programmed by regional agencies (MTC)

Sales Tax

Rollover of Contra Costa County Measure C in 2008

SHOPP

State Highway Operations and Protection Plan — state highway funds available to Caltrans to maintain & operate state highways

TCRP (bore)

Governor’s Traffic Congestion Relief Plan - $20 million for new 4th Bore

TCRP (bus)

Governor’s Traffic Congestion Relief Plan - $40 million for new regional express buses

TETAP

Traffic Engineering Technical Assistance Program —MTC-funded traffic engineering consultants available to cities/counties for local street operations evaluation

TIP

Transportation Improvement Program —federal transportation funds available to the region

TLC

Transportation for Livable Communities — MTC program provides grants to plan and construct projects that improve community vitality

Private

Employer subsidized (capital and/or operating costs)

What are the Key Funding Issues?

Project funding for the corridor improvement strategy is a major issue that remains to be addressed. For all corridor strategies, MTC has identified several potential funding sources for recommended projects, such as Interregional Transportation Improvement Program (ITIP), Regional Transportation Improvement Program (RTIP), State Highway Operations and Protection Plan (SHOPP), Traffic Congestion Relief Plan (TCRP), bridge tolls, and local sources. However, further work is necessary to secure these funds.

Key funding issues are highlighted below to help focus the discussion about project funding for the Phased Corridor Strategy.

  • Known transportation funding sources are currently committed to other projects in each county.
  • Expanded BART parking and a 4th Bore remain largely unfunded (except for the $20.0 million in TCRP towards the 4th Bore), and therefore will require substantial funding to be implemented.
  • Project priorities and "new" revenue sources for each county are periodically revisited when MTC updates the Regional Transportation Plan (RTP). If a corridor improvement strategy is deemed to have a high priority by local agencies, funds could be transferred to that strategy when MTC next updates the RTP in 2001.
  • Funding may be available for some lower-cost transit or operational improvements that would provide short-term congestion benefits.
  • Only limited funds are available for transit operations for new or expanded feeder/shuttle and express bus service.
  • While Governor Davis’ Traffic Congestion Relief Plan allocated $20.0 million and the 2000 State Transportation Improvement Program (STIP) allocated another $16 million towards the construction of the new 4th bore, this is well short of the cost estimates of $152.0 million to $401.0 million needed for various tunnel configuration options. Options for capital funds for a new bore include state/federal highway funds, Governor’s Plan, county sales tax, and new bridge tolls.

Collecting tolls at the tunnel (which would help pay for the new tunnel) would not likely attract many users due to short approaches to the proposed 4th Bore; tolls derived by charging non-carpoolers for use of a dedicated carpool lane (high occupancy toll lane — HOT) would generate only modest annual revenues.