With the recent opening of westbound and eastbound express lanes and general purpose lanes in Riverside County, southern California's massive State Route 91 Corridor improvement project is finally nearing completion. Now over 90 percent complete, the 91 Project is expected to be finished by the end of the year.

The Riverside County Transportation Commission (RCTC) is partnered with Caltrans, the city of Corona, Riverside County, the Orange County Transportation Authority, and the U.S. Department of Transportation on the $1.4 billion project, which extends from the Riverside County/ Orange County line in Corona to Pierce Street in Riverside. The project is adding regular lanes, tolled express lanes and connectors, and making improvements to interchanges, bridges, ramps and local streets. New connections between the 91 and Interstate 15 are also part of the project.

Anne Mayer, RCTC Executive Director, said the opening of the new lanes fulfills a promise made by transportation officials. "We're getting it open in the spring as we projected we would do. It's extremely challenging to build a project of this complexity and magnitude under live traffic conditions. This team has done an amazing job."

The SR 91 Corridor Improvements design-build project includes extending the existing OCTA SR 91 express lanes 8 miles east to I-15 and widening the existing interstate from five to eight lanes in each direction, which includes expanding the single HOV lane to two express toll lanes, adding one general purpose lane, and adding an auxiliary lane to manage off/on traffic. The project also includes improvements to the I-15/SR 91 interchange, 3 miles of improvements on I-15, and a tolled express lane direct connector from eastbound SR 91 to southbound I-15.

These improvements are designed to reduce delays, offer a choice between regular lanes and express lanes, allow faster emergency response, relieve local street congestion and provide better access to public transit and trails.

Issues From Rapid Growth

Afternoon traffic congestion on State Route 91 between Orange County and Riverside County is among the top trouble spots in the nation. The 91 in Riverside County ranks among the nation's worst commutes. Stop-and-go traffic is the norm, especially during morning and late afternoon rush hours. In fact, traffic congestion on eastbound 91 between Anaheim and Corona is routinely among the worst five areas in the nation.

The 91 Freeway is approaching 50 years old, and the traffic demands now placed on it far exceed its original design from the early 1960s. Close to 280,000 vehicles travel this section of the 91 each day, and that number is expected to grow by another 140,000 vehicles daily by 2035. The 91 is the only major east-west route between Orange County and Riverside County and is used heavily for commuting, commercial transport and local travel.

Studies indicate that once the project is complete, users of regular lanes can save an average of 12 minutes per day when traveling round-trip during peak morning and afternoon hours. Users of the Riverside County 91 express lanes can save an additional 78 minutes daily, compared to using the regular lanes.

With rapid growth of Riverside County in the 1980s, traffic congestion along the route was an ever-increasing problem, even after express (toll) lanes opened in 1995. Adding to the problem was the private owners' 35-year contract with Caltrans, which prohibited lane additions on the 91 that might mean less traffic on the tollway, and gave the express lane owners veto power over any projects.

This controversial situation continued until 2003, when the OCTA purchased the 91 express lanes and eliminated the non-competition agreement; soon thereafter, the ambitious efforts to improve the route began. Environmental approvals for the project were received in late 2012, and construction commenced in 2014.

As RCTC officials point out, such a large project - when built using a traditional design-bid-build method - will normally take about seven years to complete.  However, for the 91 project the Commission is using a design-build method, which has saved several years in construction time.

A joint venture team headed by Atkinson Contractors and Walsh Construction Company was awarded the design-build contract for the project in 2013; URS is the lead designer. Funding for the project is provided by a combination of federal, state and local sources, as well as toll revenue bonds. The express lanes will be fully funded by tolls from drivers who choose to use those lanes. Toll revenue will be used to repay the federal loan for the project.                    

The scope of work includes 32 bridges, 100 retaining walls totaling nearly 1 million square feet, 200,000 cubic yards of PCCP paving, and 290,000 square feet of sound walls.

Keeping the Public Informed

Throughout the project, construction crews have worked to reduce delays by maintaining the current number of lanes on the 91 and I-15 during peak travel hours, unless any lane reductions were deemed absolutely necessary. Lane reductions typically only occurred outside of peak travel times.  One traffic interruption was much more significant, however.

Through intensive planning, inter-agency coordination, and community support, the RCTC project team was able to fully and successfully close eastbound and westbound 91 for a full weekend in February of 2016. The 55-hour full closure of the 91 between the 71 and I-15 allowed crews to consolidate three major work efforts: demolishing the west half of the Maple Street Bridge, building the support structure for the new westbound Maple Street on-ramp flyover bridge, and paving the eastern end of the project near I-15.                                     

This effort, referred to as the "91 Steer Clear" campaign, set a goal of limiting traffic delays to 30 minutes, by warning motorists of potential delays of three hours and encouraging use of alternate routes and transportation modes. Due to public outreach efforts - billboards, signs, radio ads, social media posts, news coverage, email reminders, business and agency briefings, a public meeting and webcast, and detour maps - motorists avoided the area, and traffic delays were fewer than 30 minutes. 

"The 91 Steer Clear was an incredible success," reports Mayer. "The way to approach a complex operation like this is to plan the work, and work the plan - and that's exactly what we did. The teamwork with the city of Corona, County of Riverside, California Highway Patrol, Caltrans and our neighboring agencies was essential and made this operation work as well as it did."       

Project Challenges

A project this massive does not come without its share of challenges and delays.  Parts of the work, including several ramps and a 3,700-foot toll bridge connecting I-15 to the 91, fell behind schedule. In the fall of 2015, heavy rains required the closure of two westbound 91 lanes and caused an hours-long traffic jam. A month later, an on-ramp under construction fell 16 inches during a lowering operation, injuring 10 construction workers. The bridge was demolished and rebuilt due to structural concerns. More recently, completion of an on-ramp to the 91 was delayed by more than a month when grading crews hit a hazardous materials barrel near an abandoned gas station.

Although new lanes are now open, construction activity will continue until late 2017; however, with the end in sight, crews are now focusing on final bridges, ramps and roadways through the project limits. Motorists will continue to encounter nightly closures of eastbound 91 at Interstate 15 for work on the Express Connector, which will link northbound I-15 to westbound 91 and eastbound 91 to southbound I-15. This massive flyover structure measures 3,700 feet long and 70 feet tall.

The 91 Project will provide significant benefits to drivers, residents and businesses along a heavily traveled corridor. Once completed, the new lanes and other improvements are expected to save time, offer choice and reliability, boost safety, enhance access and job creation, promote ridesharing, reduce pollution and aid the movement of goods along the region's roadways.