Project Status: Active Construction

Project Background

Numerous traffic circulation studies for the Avila area have repeatedly identified the Avila Beach Drive at US 101 interchange as being inadequate to meet circulation needs for community build-out. The existing five-legged intersection of the US 101 southbound ramp, Avila Beach Drive, and Shell Beach Road experienced significant congestion during peak hours, especially during weekend peak period. The general increase in traffic, coupled with the anticipated future traffic from planned projects in the area, was forecast to degrade this intersection to a Level of Service 'F' by 2032 due to future traffic delays and congestion. 

Project Benefits

When completed, the Project will improve the operations and multimodal access of Avila Beach Drive at the northbound and southbound US 101 off-ramps by improving intersection efficiency. The increased efficiency of the single lane roundabout will reduce current and future delays resulting in reduced congestion while providing for safer vehicular movements.

The proposed intersection improvements consist of three main components:

1. Replacing the existing stop-controls at the southbound ramp and Shell Beach Road intersection with a single-lane roundabout to improve efficiency.
2. Modifications to the northbound off-ramp to improve sight distance for vehicles.
3. A Park & Ride lot and a Regional Transit Authority (RTA) bus stop at the southwest corner of Avila Beach Drive and Shell Beach Road.

Project Cost

A construction contract was awarded by the County Board of Supervisors to CalPortland in the amount of $13,839,594 to construct the project. The project is currently funded by numerous federal and state grants, including $10,065,000 in Federal Congestion Mitigation and Air Quality (CMAQ) funds, $911,843 in Federal Highway Improvement Program (HIP) funds, $6,810,000 in State Transportation Improvement Program (STIP) funds, and $605,380 in County General funds.

Project Timeline

Construction on this project began in April 2024 and anticipated to be complete by January 2026. Construction activities have been separated into five distinct phases to promote community and worker safety during construction. In doing so, the construction phases will create:

1) separate and distinct work areas for construction and county staff to safety implement their work, and

2) separate and distinct travel areas for commuters and cyclists to safely navigate the intersection with minimal disruptions.

The working areas and travel areas throughout each phase will be delineated by traffic control devices such as signage, cones and concrete barriers.

Construction Stages

The various construction phases and anticipated implantation schedules are shown below.

STAGE 1A AND 1B: COMPLETE

During Stage 1A and 1B, the underground facilities, including storm drainage and electrical conduits that will serve the project upon completion were constructed. 

Additionally, temporary US 101 on-ramps and off-ramps were constructed that will allow for continued traffic operations while the final on-ramps and off -ramps are constructed under future phases. This stage also constructed the retaining walls at the US 101 embankments. The retaining walls were constructed in a manner that makes them resemble natural rock outcroppings that occur in the nearby hills to help blend the project into the natural environment.

STAGE 2: ACTIVE THROUGH APRIL 2025

During Stage 2, traffic on US 101 southbound off-ramp and on-ramp was routed onto temporary ramps constructed under Stage 1, allowing the contractor to remove the existing ramps and construct new permanent ramps. Traffic on Avila Beach Drive was shifter to the south allowing for the construction of new curb, gutter and sidewalk. New curb, gutter and sidewalk will also be constructed on the west side of Shell Beach Road.

STAGE 3: WILL BEGIN MAY 2025

During Stage 3 curb, gutter, and sidewalk will be constructed on the east leg of Avila Beach Drive, the central portion of Shell Beach Road realignment will be constructed along with the US 101 Southbound On-ramp. New temporary striping will be installed to accommodate for the slight variations in temporary traffic alignments.

STAGE 4: WILL BEGIN JULY 2025

During Stage 4, the US 101 Interchange at Avila Beach Drive will be closed for forty days. The closure is required to construct the central portion of the roundabout which will be located at the intersections of Avila Beach Drive, Shell Beach Road and the southbound US 101 off-ramps and on-ramps. Traffic will not be able to pass through the project site during the 40-day closure. Vehicles accessing and utilizing US 101 will do so via San Luis Bay Drive to the north and Spy Glass Road to the south.

Message boards will be in place during the closure to inform the public that local roads and businesses will remain open and accessible from the San Luis Bay Drive and Spy Glass Road exits. To accommodate anticipated added traffic at San Luis Bay Drive, traffic flagging crews will be in place during peak periods to direct and clear traffic queues and mitigate any potential delays.

Construction activities occurring during Stage 4 will include constructing the roundabout curb, gutters, medians, and center island, and will also include construction of sidewalk on Avila Beach Drive. Final paving, traffic striping, signage, and lighting will be installed for the roundabout at this time.

STAGE 5: WILL BEGIN AUGUST 2025

During Stage 5, the Park and Ride Facility will be constructed and paved. The roundabout will be open to the public during this stage.

Anticipated Construction Completion Date: January 2026