San Diego has long been a hotbed of transportation innovation, and next year the state will break ground on a landmark freeway improvement project that promises to change the face of travel along a heavily congested portion of Interstate 15, between Route 163 in San Diego and Route 78 in Escondido.
The California Department of Transportation, or Caltrans, plans to begin construction in fall 2003 on the first of three segments of the I-15 Managed Lanes Project. The project will be the first of its kind in the state.
"It will be similar to what's out there now with the I-15 express lanes, but with some significant improvements," said Caltrans Project Manager Larry Carr.
The project will construct four lanes in the freeway median instead of just two. And while separated from the regular lanes by a fixed concrete barrier, a movable barrier such as that used on the San Diego-Coronado Bridge will be used to configure the new lanes.
"Given the traffic flow is heavy southbound in the morning and northbound in the evening, the lanes could be set for three lanes in the heavy direction and simply reversed at mid-day or late evening," Carr said. "It's basically getting the benefit of six lanes for the price of four."
The movable barrier will also be used to configure the lanes in case of special events or emergencies.
Another improvement will be access points to the I-15 managed lanes. The express lanes between Route 163 and Route 56 have been criticized for having access only at the end -- precluding their use by large communities like Poway, Mira Mesa and Scripps Ranch. "We're doing our best to provide access to the managed lanes for everyone in the corridor," Carr said.
The most significant new feature of the project is its transit element. Caltrans and the Metropolitan Transit Development Board have worked closely to develop this concept. MTDB Project Manager Sandy Johnson said transit centers with park & ride lots are planned adjacent to the freeway in Mira Mesa, Sabre Springs, Rancho Bernardo, the North County Faire shopping center and Escondido. These will connect directly to the managed lanes via bridges, allowing users to bypass ramps. Buses will be able to operate at high speeds along the corridor.
"The managed lanes project will be a transit trunk line when completed," Johnson said. "It will operate like a 'rubber-tire' trolley system -- with more flexibility than light-rail, and at a fraction of the cost."
This Bus Rapid Transit System is part of MTDB's regional "Transit First" vision.
The I-15 managed lanes will be in addition to the existing main lanes, so much-needed freeway capacity and congestion relief will be provided along the corridor, according to Carr. He added that the managed lanes would be available free to buses and carpools. The excess capacity in the new lanes may be sold to single drivers for a value-pricing fee. Value pricing is a variable fee based on the number of vehicles using the main lanes at the time.
The estimated cost for the entire I-15 Managed Lanes Project is $750 million. In a highly successful effort, Caltrans, the San Diego Association of Governments and MTDB have together gathered $375 million from various sources to construct the middle eight-mile segment. With forecasts predicting traffic increasing from 280,000 to 380,000 trips a day during the next 18 years, the improvements are critically needed. Without them, traffic delays could average two hours or more in the future.
The middle segment will break ground in fall 2003, and is expected to open to traffic in 2006. It is the most important of the three segments, stretching from Route 56 to Centre City Parkway, where most of today's daily traffic congestion occurs. The I-15 Managed Lanes Project's south segment, from Route 163 to Route 56, and the north segment, from Centre City Parkway to Route 78 in Escondido, will be constructed as funds become available.
This project is becoming a reality years ahead of schedule, thanks in part to $70 million provided by Governor Gray Davis and his Traffic Congestion Relief Program. The $5.3 billion program is the single largest general fund in investment in transportation in state history. The TCRP has helped fund 141 projects statewide.
"I think it's important to note that this project -- combining traditional freeway lanes, movable barrier, value pricing and a Bus Rapid Transit System -- isn't merely 'enlightened' thinking," Carr said. "We've worked very hard with Sandag and MTDB on studying different options, and the analyses show this to be the most cost-effective solution. This project will change the way we view conventional freeways and likely serve as a model for the state, if not the nation."
Saville is chief public information officer at Caltrans.