San Diego’s Mission Valley East Trolley Extension

In 1987, a group of visionary local elected officials, business and civic leaders concerned with the level of state and federal funding for the region’s transportation needs, proposed a half-cent TransNet sales tax initiative that would augment existing funds for roads, freeways and light rail projects.

Voters shared in that dream and passed the tax initiative measure. That was the beginning of an incredible success story in the San Diego region — the Mission Valley East extension of the San Diego Trolley.

Now that the $500 million project is complete and exceeding all ridership projections, no one seems the least bit surprised. During the 30-year process of building the line — cutting through the heart of the city and serving massive San Diego State University — there was never much doubt that it would be a success.

But major challenges involving the route, the cost, the constructability and the potential environmental impacts all made it very difficult to make final decisions and move forward.

The Mission Valley East project completed the San Diego Trolley’s third line — the “Green Line.” It started carrying paying customers in July 2005. Beginning at the Old Town Transit Station north of downtown, the line runs east through Mission Valley and stops at Qualcomm Stadium, then detours onto the SDSU campus, links up with the Orange Line in La Mesa and traverses El Cajon before terminating in Santee.

Mission Valley East was the final section of the Green Line, filling in the 5.9-mile gap between Qualcomm and Grossmont Transit Center in La Mesa. It closed a giant loop made up of all three trolley lines.

Planners initially projected that by 2010 daily boardings would be about 7,300 at the four stations added with the Mission Valley East extension. In the fall of 2005 this number was at 4,500 and continued to grow to 5,700 in the fall of 2006 — a 25 percent increase.

It also provided immediate congestion relief on the nearby roadways, diverting 4,600 trips from automobile to transit, and reducing parking demand at SDSU by 2,000 cars per day. On July 9, 2005, when dignitaries cut the ribbon on the new section of light rail at the impressive new underground station on the SDSU campus, a reporter quoted Representative Susan Davis as saying what just about everyone else at the event said: “Wow!”

The History
The idea of routing light rail through Mission Valley already had been in long-range plans for four years when the San Diego Trolley first opened in 1981. That year, the Metropolitan Transit Development Board (MTDB) started operating the first segment of light rail transit in the region, a 16-mile stretch from downtown San Diego to the international border with Mexico.

Over the ensuing 20 years, MTDB steadily expanded the network to 47 miles of track. Two separate lines were created — the original Blue Line, which now stretches from Old Town south through downtown and then along the coast to the border; and the Orange Line.

The first phase extension east from Old Town into Mission Valley was also built to connect transit riders to Mission Valley employment, residential, shopping and entertainment, including Qualcomm Stadium.

As the light rail system grew, the transit agency took pains to connect it with the regional bus network and the Coaster Commuter Rail system at key trolley stations and regional transit centers. San Diego Trolley passenger boardings in late 1999 averaged approximately 75,000 on a typical weekday and often reached 90,000 on special event dates such as Chargers football games.

Filling the Gap
Although the 20-year-old San Diego Trolley was a great success, the missing piece in Mission Valley was a gap preventing the trolley from creating a loop that would connect people in some of the busiest communities in the region, including the tens of thousands of students of San Diego State University that had to fight traffic to get to campus, and fight for parking spaces once they got there. MTDB began planning and designing the missing link in 1991. In general, the route was obvious: head east through Mission Valley, making sure to touch SDSU and continue on to La Mesa.

But a closer look at the details quickly brought up a series of incredibly difficult challenges, largely focused on how best to serve the university campus.

The Obvious Decision
San Diego State University sits perched on a mesa overlooking Mission Valley. It is the largest and possibly most crowded campus in the state university system, with more than 35,000 students, faculty and staff.

The campus has massive traffic and parking problems. More than 80 percent of the students commute to campus. While numerous bus routes serve SDSU, the topography and impacted neighborhoods surrounding the school make fast, direct routes difficult to create.

The layout of the campus quickly presented the first challenge to light rail. While the Mission Valley-Interstate 8 freeway corridor runs along the north side of campus, the school is oriented to the south — with the entrance to the campus and the transit station, as well as a planned redevelopment area, all on the south side.

MTDB faced a choice: Place a new trolley station on the north side of campus, among remote service buildings and down a steep hillside; or loop the tracks up the hillside, under a portion of the campus and to a new underground station at the centrally located transit center.

The “heart of the campus” choice seemed obvious, but it wasn’t. Major obstacles stood in the way.

The loop route required a tunnel to access the station. Technical limitations of light rail prevented it from reaching grade by the time it could be brought up out of Mission Valley to the campus transit station. MTDB had never designed, built or operated in a tunnel prior to the Green Line.

The route was longer, and would loop out of direction for through passengers. The detour south onto the campus would cost two extra minutes for passengers not getting off at SDSU.

The loop route onto campus was expected to cost up to $75 million more than the simpler, northern route. The environmental impacts of crossing canyons and tunneling under the campus were initially unknown. The surrounding community expressed concern that the trolley would bring unwanted traffic and activity to their neighborhood and initially opposed the loop route to the southern campus entrance. Instead, community members actively supported the northern route closer to the freeway. The constructability of the loop project was a concern. The route was high on hillsides above the freeway, and the geology of the tunnel area was unknown.

The challenges seemed to overwhelm the desire to serve the heart of the SDSU campus. The MTDB moved forward cautiously, keeping both options open. Several factors led to the eventual decision to take the more expensive and difficult route — but the one that would better serve transit riders.

A design panel of experts evaluated options for increasing ridership projections at the northern location close to the freeway. The panel concluded that to achieve reasonable ridership at a northern campus station, features such as raising the station to the height of the campus, moving the bus transit center to the northern location, and reconfiguring some of the campus to improve pedestrian connections to the station and to re-orient the campus toward the station would be necessary. All these features added significantly to the cost, and made the loop route appear to make financial sense.

A value engineering team analyzed the loop and tunnel option, recommending a longer, deeper tunnel that improved constructability, and reduced uncertainty and risk. A survey of SDSU students showed that they preferred the southern loop station site two-to-one over the northern location.

A project advisory committee of area stakeholders reviewed the options, identified modifications that would help address community issues, and recommended the southern route and station.

A Station Design Review Committee, also comprised of area stakeholders, actively provided input into the design of the SDSU Station, which reflects community and campus character and history through its architecture and public art.

DSU agreed to provide an easement for the tunnel and station and to contribute to the operating costs of the station by providing maintenance outside the underground areas and using campus police to assist in station security. When all was said and done, the MTDB adopted the loop route to serve the campus. The decision was partly one of added value for added cost, because, in the end, the south side loop tunnel option proved to be more cost-effective than the freeway routing and supported the objectives of integrating the light rail stations into communities and activity centers.

However, the decision was based as much or more on the ability to resolve a number of technical issues early in the project’s development, the university’s commitment to the project and the hard-earned consensus from the community that the benefits of the loop route outweighed any lingering issues or additional costs.

As design and construction proceeded, MTDB and the North County Transit District merged with the San Diego Association of Governments (SANDAG), which completed construction of the project in July of 2005.

The Green Line
When the 5.9-mile Mission Valley East segment and its four new stations were completed in July of 2005, it allowed for the inauguration of the San Diego Trolley’s third line — the Green Line.

As predicted, the line proved to be an immediate success, particularly with students at SDSU. Ridership is on track to exceed projections for the year 2015.

The completed Green Line also has succeeded by what planners consider the most important measure — generating new transit riders. Within a few months of opening, the Green Line was generating about 18,500 daily trips, 7,200 of which were taken by new riders.

A rider survey conducted by SANDAG in October of 2005 — just four months after the completed Green Line opened — demonstrated that the line was attracting new ridership to transit.

While bus use at SDSU Transit Center had decreased slightly, the opening of the Green Line allowed for the total transit ridership as measured at the school’s transit center to more than triple, from 2,200 weekday trips to more than 7,100 weekday trips in November 2005.

Forty percent of Green Line users did not use transit at all in the previous year, including the 25 percent who relied previously on automobiles. Existing transit riders who used the Green Line were becoming more frequent transit users.

As of October 2005, the SDSU Transit Center was generating nearly 4,900 new trips each day. This corresponds to about 2,000 cars no longer driven to SDSU each day. A subsequent survey conducted by SANDAG in October of 2006 — 16 months after the Green Line opening — revealed information about the evolving ridership.

The Green Line attracted new transit riders, with 31 percent not riding any form of transit a year before, and many longer-term transit users riding more often. Approximately 17 percent of surveyed transit riders indicated they had increased their use of transit in 2006. The 31 percent who did not ride transit a year before translated into more than 6,200 new weekday transit trips. The No. 1 reason cited by SDSU station users for riding transit was not having a vehicle available. Avoiding traffic and parking were the next most cited reasons. Of those 55 percent of SDSU station users who had a vehicle available, avoiding traffic and parking were identified by 63 percent as the main reason for riding transit.

Moving Forward
It took 30 years and many tough decisions to complete, but by every measure the Mission Valley East Trolley Extension and the Green Line as a whole have been a success. In 2007, the facility was given the prestigious Project of the Year award for the State of California by the American Society of Civil Engineers (ASCE). In 2008, the ASCE has again honored the effort, naming it one of five finalists for the international Project of the Year award.

Nevertheless, SANDAG and the Metropolitan Transit System continue to push for improvement on the line, supporting programs to boost ridership and continually bring new riders to transit.

Art Madrid is the mayor of La Mesa, Calif., and board member, San Diego Association of Governments.

More Related Information:
Archived Article: Rail Modernization- It’s Not Your Father’s Rail Vehicle
Archived Article: Global Rail Safety: Equipment and Technologies
Transportation Video Network: Plasser American
Webinar: Inventory Optimization in a Transit Environment — A Bombardier Case Study
Mass Transit Buyer’s Guide: Railroad Engineering, Construction, Installation Contractors

Loading