Many of you have seen the tweet. On May 27, the city of Santa Monica tweeted a video of a machine smoothly and quickly laying down the concrete barrier for a protected bike lane. Just about everyone who saw it, from Councilmember Jesse Zwick to activists in New York and Australia, had the same verdict, “we need more of these wonderful machines.”
Selim Eren, the principal engineer with Santa Monica’s Department of Public Works, explains that the machine isn’t magical, or even some advanced technology. It’s a machine regularly used for highway projects, repurposed for bike lanes.
“This equipment is called concrete extrusion machine and it’s been around for a long time, not new in the engineering world. It’s primarily used in highway construction, and not typically used in cities or urban settings,” Eren explained in a phone interview with Next last week.
“Typically, it is used in linear and long highways for the construction of medians, curbs gutters, or even concrete pavements. A custom form is made to shape and form the concrete in place. In our installation, we used an upside down U shaped form to construct a 2 feet wide 6 inches high concrete median for protected bicycle lanes.”
I guess cities have to stop telling us it takes “too long” to install a barrier protected bikeway.
The machine work isn’t just more precise than the typical protected bike lane installation style, it’s also faster. The extrusion machine was able to create four or five blocks of protected bikeways in one day, which is several times faster than the standard installation.
“In the traditional form and pour method, a lot of inconsistencies in concrete can occur due to each custom formwork being handmade,” Eren continued. “But with this intelligent concrete extrusion machine, the final product is delivered with high accuracy and high quality. This method is very sustainable and reducing materials and waste. It saves a lot of labor time and cost. We installed, in total, over 3,000 linear feet, five city blocks of bike lanes with this machine in one single day.”
While Ocean Avenue has been open through construction, an official opening following all of the restriping and reinstallation of parking meters is planned, “soon.” After a month of metered parking next to the protected lane having been temporarily removed, the meters were back in place this week.
Until 2020, Ocean Avenue had regular “door zone” bike lanes that did little to attract cyclists. A survey completed during morning and evening rush hours in 2019 showed anemic results.
“There have been bike lanes on Ocean for many years, but they were located in the door zone, or where car doors open. With this design, 14 bikes in the morning, 4 in the evening is what we were seeing,” explains Jason Kligier, mobility manager with the Santa Monica Department of Transportation.
In 2020, the city installed bollard protected bike lanes, and the results were dramatic. The number of motorized vehicle trips dropped and the number of bicycle trips grew.
“We found that automobile traffic volume during the two periods decreased by an average of 18%. And cyclist volumes have increased exponentially,” Kligier continues. “So, where most of the intersections on Ocean Avenue in the downtown had fewer than 10 bikes in the morning and or evening rush hours in 2019, We’re now seeing between 50 to over 100…113 bikes in those same windows in 2022.”
Buoyed by these numbers, ones that the city has proudly highlighted on its social media, and spurred on by the need to accommodate outdoor eating options for restaurants on Ocean Ave. post-pandemic; the city has moved quickly, concrete extrusion machine and all, to complete phase 2 of the project with the fully protected bikeways this year.
