Less than a year from the start of construction of the Montecito portion of Highway 101: Carpinteria construction project in Santa Barbara, the Montecito Architectural Review Board heard an update from project planners on the San Ysidro and Olive Mill interchanges.
Construction on the Montecito segment, which runs just north of the Sheffield Drive underpass to the Olive Mill Road overpass, is expected to begin in 2022, according to Fred Luna, project delivery and construction manager for the Santa Barbara County Association of Governments.
Project staff updated council on Thursday afternoon, highlighting proposed plantation and bridge improvements for the San Ysidro Road and Olive Mill Road interchanges.
There are “real opportunities” for planting in the two interchange areas, and the design team is focused on skyline planting in those areas, according to landscape architect Christine Anderson.
The skyline plantings will be in line with the plantings along Sheffield Drive that the board approved just over two years ago, with additional design, Anderson said.
“We’re looking at what we call this ‘Montecito mixed boardwalk’ which would be a close up view… (and) these skyline trees that would really be in the background of anything you would see in the distance, but not up close. up, ”she said.
Some of the lowest trees would include oaks, sycamores and Monterey cypresses, while the skyline would include trees such as the Mexican palm, she said.
The other plantations that are still in the process of being decided are the improvement plantations – which will differ depending on the areas concerned – the interplantations which will use the existing plant material, the buffer plantations adjacent to local roads and the narrow planters which will be mainly filled. of low vines and shrubs, Anderson said.
At the San Ysidro interchange, the project will include improvements to the freeway ramps to meet more current design standards for the freeway as well as improved ramps that connect to local roads, according to the design engineer. Zach Siviglia.
The San Ysidro crossing bridge will not be replaced by the project, but some aesthetic improvements will be made, Siviglia said. The design team evaluated a series of alternatives for the bridge over several months and decided to sand the existing structure to remove some of the rust stains from the metal barriers at the top of the bridge, he added.
“What came out of this discussion was to keep the bridge true to its shape and look for ways to improve the existing structure, but without going too far,” said Siviglia.
The project will replace the existing metal railing at the top of the bridge with a concrete wood railing that is compatible with railings used elsewhere throughout the project, according to Siviglia.
As a HOV lane will be added to the highway, a middle barrier will need to be built. 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,” said Siviglia.
Heading south, the project involves planting Boston ivy and other lower shrub plantations similar to what was approved for the Sheffield portion of the project, according to Siviglia.
There is more space to plant in the northerly direction, where there are existing palm trees located very close to the causeway, Anderson said. Some of the existing palm trees will need to be removed or relocated during construction, but the team is also trying to conserve some of the existing trees, she added.
There will be new palm trees placed along the south-facing portion that will serve as a background visual that people can see from afar, and trees such as the cypress or Monterey oak that will be used for a vision. of the canopy, Anderson said.
Similar to the San Ysidro Bridge, the project will take on the “natural form” and “historic look” of the Olive Mill crossings by cleaning up rust spots that have occurred over the years, Siviglia said.
According to Siviglia, the railing of the southbound Olive Mill overpass was replaced after the Montecito debris flow, so it will not need to be replaced. However, the metal railing of the southbound Olive Mill access ramp will be replaced with a concrete wood railing, he added.
With the widening of the highway, it is possible to plant between the main line and the southbound slip road, and the approach will be consistent with that of the San Ysidro part, Siviglia said.
In the northerly direction, there will be space to include more planting between the ramp and the highway, according to Siviglia. The team will do their best to keep existing trees to the extent possible, but the rank changes infringe on the ability to do so, Anderson added.
Auxiliary lanes will be added throughout the section, “intended to connect the access ramp of one interchange to the exit ramp of another interchange,” Siviglia said. “This contributes to the safety of vehicles taking and exiting the highway, it gives a little more distance to make this movement safely,” he added.
Improvements to the highway between San Ysidro Road and Olive Mill Road will be in conjunction with the construction of the two roundabout projects in these areas, Luna said.
“(It) will really develop a community benefit project that will improve coming in one time and providing all of these upgrades, and only disrupting the community once in a build time frame,” he said. -he declares.
Road improvements throughout the corridor will also be in line with proposed improvements for roundabouts to create a “community benefit,” Siviglia added.
As construction nears, the project team will return to provide updates on creek bridges, median barrier treatments, noise and retaining walls, roadside planting, and fencing.