This project rehabilitates infrastructure along Third and Second Streets including repaving of the roadway, updating traffic signals, and plants street trees. Additionally, it integrates the Cross Marin Bikeway and enhances pedestrian safety where possible. This project’s goals and objectives are defined in the Third Street Feasibility Study, which was confirmed by City Council in July 2019.
The pavement rehabilitation includes milling the entire street area to a maximum depth of 4.5 inches, removing and replacing damaged pavement, placing a 2 inch asphalt levelling course, application of fabric, and final placement of a 2.5 inch maximum layer of asphalt. Unless otherwise noted, the streets will be re-stripped to match the current configuration except that markings will be updated to meet current standards.
To enhance pedestrian access, the project will replace curb ramps within the corridor to meet current accessibility standards. At Third Street’s intersections with A, B, C, and D Streets, the final asphalt overlay will be at the same elevation of the sidewalk. This will provide a flush transition for pedestrians to cross the street.
The project proposes to integrate the Cross Marin Bikeway into Second Street between West and Shaver Streets. This will include the construction of segments of Class IV Bikeway and a Class I Multi-Use Pathway along the south side of Second Street. To accomplish these facilities, the travel lanes will be shifted to the north requiring modifications to the existing medians. In addition, the project will construct a retaining wall that ranges from 24 to 48 inches in height along the hillside south of G Street. This option will require the removal of about 12 on street parking spaces.
The project upgrades traffic signals at Third Street’s intersection with Grand Avenue, Irwin Street, Tamalpais Avenue, Lincoln Avenue, Lindaro Street, A, B, C, D, E, and Shaver Streets. In addition, it upgrades the traffic signal at the intersection of Second and G Streets. This work includes replacing poles, mast arms, conduits, conductors, and signals with current standards. This includes a change to the B and Third Street intersection from one way to two way operation. Finally, the project will install new traffic signals at the intersection of East and Second Streets as well as Brooks and Third Streets. The project will install conduits along Third Street in select locations to accommodate traffic signal interconnect, fiber optic communications, and street light electrical conductors.
The project will rehabilitate the sanitary sewer system within the entire area. This work includes excavation and replacement as well as pipe bursting of pipelines at select locations. In addition, the project will replace both sewer laterals as well as several manholes at locations where the pipelines are rehabilitated.
To accommodate the modifications at the intersections, the project proposes to install storm drainage infrastructure. This work includes excavations of up to 5 feet deep and the placement of pipelines, inlets, and maintenance holes.
Marin Municipal Water District proposes to upgrade its water line prior to re-paving of the roadway. This includes the installation of a six inch welded steel pipe along Third Street between Second and Hayes Streets as well as along Hayes Street between Third and Second Streets. In addition, the project will install an 8 inch welded steel pipe between E and Irwin Streets. The pipelines will be placed by traditional excavation methods to a depth of at least 30 inches. Other public utilities will adjust their infrastructure as necessary to support the project.
To construct the elements as detailed, the project will need to remove up to three trees. Two of the trees are located along Second Street and one is located at the south east corner of E and Third Streets. The project proposes to plant up to 40 new street trees.