Less than a year out from the commencement of construction for the Montecito portion of the Highway 101: Carpinteria to Santa Barbara construction project, the Montecito Board of Architectural Review heard an update from project planners about the San Ysidro and Olive Mill interchanges.
Construction on the Montecito segment, which runs from just north of the Sheffield Drive undercrossing to the Olive Mill Road overcrossing, is expected to begin in 2022, according to Fred Luna, director of project delivery and construction for the Santa Barbara County Association of Governments.
Project staff gave an update to the board on Thursday afternoon, highlighting the planting and bridge enhancements proposed for the San Ysidro Road and Olive Mill Road interchanges.
There are “real opportunities” for planting in the areas of the two interchanges, and the design team is concentrating on skyline planting in those areas, according to landscape architect Christine Anderson.
The skyline plantings will be consistent with the plantings along Sheffield Drive that the board approved a little more than two years ago, with some added design, Anderson said.
“We’re looking at what we call this ‘mixed Montecito parkway’ that would be a close-up view … (and) these skyline trees that would really be in the background of everything that you would see in the distance, but not close up,” she said.
Some of the lower trees would include oaks, sycamores and Monterey cypress, while the skyline would include trees such as the Mexican fan palm, she said.
Other plantings that are still being decided upon are enhancement planting — which will differ based on the areas involved — infill plantings that will utilize existing plant material, buffer planting that is adjacent to local roads, and narrow planters that mostly will be filled with vines and low shrubs, Anderson said.
At the San Ysidro interchange, the project will include upgrades to the freeway ramps to meet more of the current design standards for the freeway as well as improving the ramps that connect to local roads, according to design engineer Zach Siviglia.
The San Ysidro overcrossing bridge will not be replaced with the project, but some aesthetic enhancements will be provided, Siviglia said. The design team evaluated a series of alternatives for the bridge over several months and decided to sandblast the existing structure to remove some of the rust stains from the metal barriers on top of the bridge, he added.
“What came out of that discussion is to keep the bridge true to form and look at ways to enhance the existing structure, but not go too overboard,” Siviglia said.
The project will replace the existing metal railing on top of the bridge with a concrete timber railing that is consistent with railings used elsewhere throughout the project, according to Siviglia.
As an additional HOV lane will be added to the highway, a median barrier will need to be constructed. The barrier will be a continuation of the barrier chosen in previous project segments to serve as a “unifying element that is used throughout the corridor,” Siviglia said.
In the southbound direction, the project will provide planting of Boston ivy and other lower shrub plantings that are similar to what was approved for the Sheffield portion of the project, according to Siviglia.
There is more space for planting in the northbound direction, where there are existing palm trees located very close to the roadway, Anderson said. Some of the existing palm trees will need to be removed or relocated during construction, but the team is trying to keep some of the existing trees as well, she added.
There will be new palm trees placed along the southbound portion that will serve as a background visual that people can see from the distance, and trees such as Monterey cypress or oak that will be used for a canopy vision, Anderson said.
Similar to the San Ysidro bridge, the project will embrace the “natural form” and “historic look” of the Olive Mill overcrossings by cleaning up the rust stains that have occurred over the years, Siviglia said.
The railing on the southbound Olive Mill overcrossing was replaced after the Montecito debris flow, so it will not need replacement, according to Siviglia. However, the southbound Olive Mill onramp metal railing will be replaced with a concrete timber railing, he added.
With the widening of the freeway, there is an opportunity to plant in between the mainline and the southbound onramp, and the approach will be consistent with that of the San Ysidro portion, Siviglia said.
In the northbound direction, there will be space to include more plantings between the ramp and the freeway, according to Siviglia. The team will try its best to keep the existing trees where possible, but the changes in grade are encroaching on the ability to do so, Anderson added.
There will be auxiliary lanes added to throughout the section, “intended to connect the onramp at one interchange to the off-ramp at another interchange,” Siviglia said. “That helps with safety for vehicles merging on and off the freeway, it gives a little more distance to make that safe movement,” he added.
The highway improvements between San Ysidro Road and Olive Mill Road will be in conjunction with the building of the two roundabout projects in those areas, Luna said.
“(This will) really develop a community benefit project that will enhance coming in one time and delivering all of those improvements, and only disrupting the community a single time within one construction time frame,” he said.
The highway improvements throughout the corridor will also be conforming with the improvements that are proposed for the roundabouts to create a “community benefit,” Siviglia added.
As construction draws nearer, the project team will come back to present updates on the creek bridges, median barrier treatments, sound and retaining walls, roadside planting, and fencing.
— Noozhawk staff writer Jade Martinez-Pogue can be reached at firstname.lastname@example.org. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.