The Authority occasionally funds the development of Corridor Studies to evaluate the benefits and drawbacks of a variety of capital and operational improvements that could be implemented within a specific corridor to achieve the Authority's overall goals of reducing future congestion on highways and arterial roads, and expanding safe, convenient, and affordable alternatives to the single-occupant vehicle.
Examples of some of the more recent corridor studies are as follows:
SR-239 Corridor Study: SR-239 is a legislatively approved, but unconstructed route in the California state highway system. The purpose of this study is to determine the ultimate concept and alignment for the route in the context of the regional transportation network that includes part of three counties: Contra Costa, San Joaquin and Alameda. This route has the potential to provide improved regional connectivity, job realization, congestion relief, and roadway safety & emergency access. Contra Costa County was awarded $14 million for initial study and planning under SAFETEA-LU in 2005. Administration of the study, now called TriLink, was transferred to the Contra Costa Transportation Authority (CCTA) in January 2012.
Corridor System Management Plans: As part of the passage of Proposition 1B in November 2006, the Corridor Mobility Improvement Account (CMIA) was created by the California Transportation Commission (CTC). The CTC requires Caltrans to develop Corridor System Management Plans (CSMPs) for highway corridors containing projects slated to receive CMIA funds. CSMPs are designed to identify ways to increase transportation options, improve system efficiency, and reduce congestion in some of the State's most challenging travel corridors. In Contra Costa County, three CMIA-funded projects have spurred the generation of CSMPs: Caldecott Tunnel Forth Bore (SR-24), I-80 Integrated Corridor Mobility Project (I-80 West) and SR-4 East Widening Project (SR-4). CSMP fact sheets, executive summaries, and full reports are posted on Caltrans' Corridor Mobility website, as they become available.
State Route (SR) 4 Integrated Corridor Analysis Final [PDF-1.6 MB]: The purpose of the plan is to consolidate the Action Plans for SR 4 (West, Central, and East) into a cohesive corridor plan that: 1) identifies and prioritizes previously indentified projects along the corridor; 2) develops and evaluates new projects, including transit options and arterial operational improvements; 3) advances local community goals for Priority Development Areas (PDAs) along the corridor; and 4) establishes a consistent set of Multi-modal Transportation Service Objectives (MTSOs) for incorporation into future Action Plan updates. It is anticipated that this corridor-level plan will be developed through an intensive, collaborative, multi-jurisdictional planning process. The Plan should provide an integrated, multi-modal approach for managing the SR 4 freeway, supporting arterials, transit services, and operational programs such as 511 Contra Costa.
I-680 HOV/Express Bus Access Study - Final Report [PDF-7.7 MB]: A primary goal of the I-680 HOV/Express Bus Study is to identify the best investment option(s) for HOV and express bus operations in the Contra Costa I-680 corridor, including access to the Pleasant Hill and Walnut Creek BART Stations, as defined by Regional Measure 2 (RM 2).
I-680 Investment Options Study [PDF-2.3 MB]: the Authority has studied various options for congestion management along I-680, ranging from the extension of HOV lanes to the extension of rail service from Walnut Creek south to Dublin.
East Central Traffic Management Study [PDF-662 KB]: the Authority worked extensively with TRANSPAC and TRANSPLAN in Central and East Contra Costa County to help find ways to make the morning commute a little easier. The study evaluates various strategies for keeping regional traffic on Route 4, and local traffic on the arterial streets. A primary strategy for traffic management that was explored in this study was the use of "single point metering," where through traffic is metered at an existing intersection to reduce downstream congestion and improve system operations.
Central, East, Southwest Arterial and Freeway Ramp Metering Study 2003: [PDF-8.8 MB] as part of a discussion of ramp metering at the local level, the regional transportation committees for Central, East, and Southwest (TRANSPAC, TRANSPLAN, and SWAT) worked with, Caltrans and the Authority to perform a technical analysis of the impacts and benefits of ramp metering arterial and freeway ramp metering. This comprehensive study examined in detail the benefits and drawbacks of ramp metering, with a strong focus on impact to surface streets.
Other Plans & Studies
In addition to the Countywide Comprehensive Transportation Plan, the Authority is involved in a variety of other plans and studies. These studies fulfill the requirement in Measure C for the Authority to "conduct transportation and growth management studies." This website will be updated as other studies are completed.