By Dave Gildea

Special to The Almanac

There are new bike lanes across the overpasses where Sand Hill Road crosses Interstate 280. The heroes for this are Don Horsley, San Mateo County supervisor, and Joe Lo Coco of the county's Department of Public Works.

Several previous efforts for improved bike lanes for this intersection had failed because the designs were not acceptable to Caltrans, or funds for the projects depended on grants from Caltrans and the agency did not approve the grants. Horsley solved the second problem by successfully pushing for a $120,000 allocation from the county budget for the project. Lo Coco resolved the first problem by working with bike advocates for a design that was acceptable to Caltrans.

The zone where Sand Hill Road crosses I-280 has long been known to be dangerous for bicyclists. The overpass in the westbound direction had a center bike lane with a substandard narrow width that was only semi-visible with white dashes. Bicyclists were passed on both sides by cars traveling at high speeds within a few feet of them. Cars changed lanes across the bike lane at any point.

The eastbound direction overpass was even worse. High-speed drivers mixed with bicyclists in the same traffic lane. Cars from southbound 280 would come around the cloverleaf at near freeway speeds to immediately merge into the same lane as the eastbound bikes.

San Mateo County Transportation Information Management System (TIMS) data from 2005 to 2013 showed that there were more car-bike collisions at the Sand Hill-280 intersection than at the Woodside-280 and Alpine-280 intersections combined, even before the Alpine intersection was improved in 2013 after there was a fatal truck-bike collision.

Several thousand recreational bicyclists ride Sand Hill Road across the I-280 intersection each week as a part of the nationally known Portola "loop." Bike riders from the Midpeninsula cross this intersection to ride up to Skyline and the coast. Bike commuters who live west of I-280 cross this intersection for jobs in Menlo Park, Palo Alto and Stanford.

The project to improve bike safety at the Sand Hill Road-280 intersection started with a chance encounter between me and Supervisor Horsley at an April 2016 fundraiser for Marc Berman, who was running for state Assembly. Horsley was immediately responsive and sensitive to the general issue of bike safety, and following this meeting, Bill Kirsch, Cindy Welton and I formed an ad hoc group to work with Horsley for bike safety improvements at several sites in south San Mateo County.

The Sand Hill Road crossing of I-280 was one of the most hazardous of these sites. Although both Bill and Cindy were members of the Menlo Park Bike Commission, and Menlo Park City Council members Ray Mueller and Kirsten Keith supported the effort, the ad hoc group had no official ties to any official government organization or even to any other bike group. The ad hoc group organized several site visits, many meetings and hundreds of communications with government officials. Many other bike advocates, especially John Langbein, contributed. The goal was to achieve greater bike safety while maintaining the same level of automobile throughput.

The eastbound and westbound directions for Sand Hill/280 had different challenges. For the eastbound direction, Caltrans had previously stated that the overpass would not accommodate a bike lane unless the overpass was widened. This would require a cantilever construction which would certainly exceed the county's funds. We didn't understand Caltrans' reasoning, but decided to live with it and focus on the westbound direction.

Lo Coco worked with Nikki Nagaya of the Menlo Park Department of Public Works and the ad hoc group for a design for a complete continuous westbound bike lane that included sharrows for a crossover from right to center for the westbound approach, a regulation-width center bike lane for the overpass and a continuation past the clover leaf after the overpass.

By August 2016 (only four months from start!), the county and Menlo Park had a design for a joint proposal to Caltrans. Then, the first setback occurred. The county's Bike and Pedestrian Commission (BPAC) was reconstituted after having been quiescent, and the county decided to put the project on hold for BPAC review. Six months later, BPAC passed a resolution to approve the design.

During the interim there was discussion from some bike advocates that the eastbound direction would be a better use for the funds. Emma Shlaes of the highly regarded Silicon Valley Bicycle Coalition and Bruce Hildenbrand, a respected bike advocate, effectively joined the ad hoc group for reviewing the issues.

After some debate it was collectively decided to continue the focus on the westbound direction design. The primary reasoning was that Caltrans had previously rejected an eastbound overpass bike lane. The westbound design had already crossed several design and advocate hurdles, it was within budget and the existing road markings made it very likely that Caltrans would permit the design improvements. The key was "doing the doable."

The group hoped that relationships from a success for the westbound direction would form a platform to tackle the more controversial issues for the eastbound direction. In June 2017, Lo Coco submitted the county and city's joint proposal to Caltrans to apply for an encroachment permit that would allow the county to implement the design.

Then, in September 2017, there was a second setback when Caltrans unexpectedly scraped all the existing road markings for both eastbound and westbound overpasses. Apparently, the Caltrans department that eliminated the markings was not coordinating with the Caltrans department that was reviewing the encroachment permit that included the westbound overpass.

Lo Coco took a proactive approach, reasoning that Caltrans' scraping of both overpasses might be an opportunity to get bike lanes for both. He submitted a new design proposal to Caltrans for center green bike lanes for the overpasses in both directions. This effectively replaced our prior request of the westbound direction bike lane for the approach, overpass and continuation. Lo Coco politicked with Caltrans that since the overpasses needed new markings anyway, the agency could use the county funds for green bike lanes for markings for both overpasses.

Meanwhile, the Sand Hill Road overpasses were even more dangerous with no markings at all. Many people tried to communicate with Caltrans staff directly or through Supervisor Horsley or state Assemblyman Marc Berman to tell them that the overpasses with no markings were extremely dangerous for both cars and bikes. It is hard to know whether Caltrans received any of these communications. The overpasses remained in this exceedingly dangerous state with no road markings for five months until last February, when Caltrans unexpectedly renewed the prior old markings.

Then sometime in early 2018 Caltrans accepted Lo Coco's proposal for bike lanes for both overpasses. In June (26 months from start) Caltrans installed the new green bike lanes.

Bicyclists are generally thrilled with this result. We are not sure why Caltrans changed its position to allow the bike lane on the eastbound overpass, but we are very happy with the result. The next project is to improve the bike lane for the westbound approach to the intersection where the bike lane and car traffic for northbound I-280 toward San Francisco cross each other.

Bicycle riders want to express their appreciation to Supervisor Horsley and Joe Lo Coco of the county public works department for their proactive work for the success of this project.

The writer of this article, Dave Gildea, is a local bicyclist and bike-safety advocate.