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29 Interstate Freeway FIGURE 21 Virginia Freeway 267 eastbound BBS. CASE STUDY 4--SAN DIEGO, CALIFORNIA trans to allow for the implementation of a 1-year pilot proj- ect. This agreement describes the key elements and strategy Background for the planning, design, and implementation of this project. After gaining approvals from key agencies the demonstration A key element of SANDAG's Transit First strategy is the use project opened in December 2005. Figure 23 shows the BBS of transit priority measures along freeways and arterials to segments that were implemented. bypass congested areas. These measures are expected to in- crease transit speeds and improve schedule reliability. Use of the BBS lanes is restricted to authorized buses only ("Transit Lane Authorized Buses Only" signs are The SANDAG BBS demonstration project will evaluate posted). No special pavement markings are used to define the feasibility of converting freeway shoulder lanes on the BBS. Buses are only permitted to use the BBS lanes SR-52 (between Kearny Villa Road and I-805) and I-805 when speeds on the general traffic lanes drop to 30 mph or (between SR-52 and Nobel Drive) to transit-only lanes that less. When using the shoulders, buses are only allowed to would be used by existing express Route 960. This project travel at 10 mph faster than traffic in the general traffic includes a formal agreement between SANDAG and Cal- lanes.

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30 West Falls Church Metrorail Station Bus Bypass Shoulder Metrorail Station Bus Access FIGURE 22 West Falls Church Metro Station BBS terminals. Project Purpose Determine the impacts to travel time reliability. Monitor the operating benefits and safety of the con- The purpose of the BBS pilot project is to demonstrate the version of the shoulder lanes to transit lanes. operational feasibility of buses using freeway shoulders as Assess the applicability of converting freeway shoul- transit lanes. The project will: ders to transit lanes on other freeways sections. Address the requirements of existing Caltrans policy on shoulder use. Project Description Address the requirements of Street and Highway Code Section 149 regarding Preferential Lanes. The project involves a 1-year pilot implementation of the Develop interagency agreements regarding liability, transit shoulder lanes to evaluate operational and safety im- maintenance, and enforcement. plications. The results will be used to assess the potential of Ensure coordination with FHWA on the I-805 segment. expanding the use of transit shoulder lanes in other freeway Develop performance measures and monitoring param- corridors. eters for the project. Prepare a final report for approval to implement the The preparation of the proposed project required that project. SANDAG assemble a multidisciplinary team from SANDAG, Caltrans, CHP, and transit operator (Metropolitan Transit Sys- The following benefits are anticipated: tem), to study and implement the project. Figure 24 illustrates the program's partnership signage. Implement Transit First Vision. Demonstrate the usefulness of freeway shoulders as Performance Measures transit lanes during periods of heavy congestion for transit operations. SANDAG and Caltrans prepared a monitoring plan to as- Measure bus passenger, bus driver, and automobile sess the expected versus actual effects of the proposed transit driver perceptions. lane. Initially, the transit lane alternative will be evaluated and

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31 FIGURE 23 SR-52/I-805 proposed transit lane demonstration segments. compared with the existing condition for the following perfor- Although transit vehicles have been using freeway shoulder mance measures: lanes safely and successfully in Minnesota for 12 years, there is no analogous California experience. There has been agreement Transit travel time reliability; for some time now between Caltrans District 11 and SANDAG Automobile driver, transit driver, and transit passenger staffs on the potential benefits of freeway shoulder lane use to perceptions; existing freeway express transit and future Bus Rapid Transit Traffic and transit vehicle operations; and services. Currently, however, the California Streets and High- Safety. ways Code prohibits use of shoulder lanes as travel lanes. Allowing even a limited number of transit vehicles in the shoul- ders during the peak period is apparently not allowed either. To Once the initial evaluation is complete, SANDAG and address these restrictions, a demonstration project was devel- Caltrans will prepare a Monitoring Plan that will lay out oped in which the shoulder lanes are converted to transit-only roles, responsibilities, data needs, and measurement methods lanes. Pull-out areas outside of the transit-only lanes were cre- for ongoing project monitoring and reevaluation. The plan ated for enforcement activities and disabled vehicles. will be framed around the four major issues noted previously and designed to answer the basic questions noted in the The California State Streets and Highways Code allows "Project Purpose" described earlier. for creation of transit-only lanes provided engineering studies are conducted on the effect of such lanes on safety, conges- tion, and highway capacity. The pilot project site is the State Route 52/Interstate 805 (SR-52/I-805) Corridor between Kearny Mesa and University City. These freeway segments represent prime candidates for the demonstration project ow- ing to the presence of several positive characteristics, includ- ing sufficient existing shoulder width, no existing or planned construction activities, and heavy peak-period congestion lev- els. Route 960 operates along the demonstration corridor with FIGURE 24 SANDAG program's partnership signage. about five morning and six evening roundtrips.