Traffic Signal Safety Improvements Project (tr2403)

Overview

The Traffic Signal Safety Improvements Project (TR2403) is a citywide effort to improve intersection safety through key signal enhancements. This includes the construction of a new traffic signal, the installation of retroreflective backplates at all existing signals, and upgraded pedestrian timing. The project supports the City’s Vision Zero and Local Roadway Safety Plan goals by reducing crashes, improving signal visibility, and modernizing aging infrastructure.

Project Location

• New signal installation: Junipero Serra Boulevard at Arroyo Drive
• Pedestrian signal upgrades: Three intersections on Grand Avenue (Spruce, Maple, and Linden Avenues)
• Retroreflective backplates: All 64 signalized intersections throughout South San Francisco

Project Goals

• Improve intersection safety for all road users
• Reduce rear-end collisions by enhancing signal visibility
• Upgrade aging or obsolete traffic signal hardware
• Increase pedestrian safety through signal timing modifications
• Ensure compliance with Caltrans and FHWA safety standards

Background

In 2022, the City completed a data-driven Local Roadway Safety Plan, which identified a high number of preventable crashes at signalized intersections. Between 2017 and 2019, 173 injury or fatality crashes were recorded at the City’s 64 signalized intersections.

Key findings that shaped this project include:

• The intersection of Junipero Serra Blvd and Arroyo Dr met traffic signal warrants and had multiple preventable collisions.
• Intersections on Grand Avenue serve dense pedestrian and multimodal activity near schools and senior housing, making them candidates for leading pedestrian intervals (LPIs).
• Sunrise/sunset glare contributed to reduced visibility of existing traffic signals, necessitating improved backplate design.

The project was awarded a $1.53M grant through Caltrans’ Cycle 11 Highway Safety Improvement Program (HSIP), supplemented by City Traffic Impact Fees.

Scope of Work

• Construct new traffic signal at Junipero Serra Blvd and Arroyo Dr
• Implement Leading Pedestrian Intervals (LPIs) at:
  • Grand Ave & Spruce Ave
  • Grand Ave & Maple Ave
  • Grand Ave & Linden Ave
• Install retroreflective backplates at all 64 traffic signals citywide
• Replace over 120 deteriorated signal heads and illuminated street name signs
• Upgrade mounting hardware and brackets

Figure 1: Key project scope elements.

Figure 2: Example of a pedestrian head start sequence, from left to right.

Project Map

Figure 3: Project overview map.

Construction Schedule

Timeline subject to change based on weather, supply chain, and field conditions.

Funding

Community Engagement

Community safety and accessibility are top priorities for this project. Key engagement activities include:

• Public noticing for construction
• Coordination with local schools, businesses, and emergency services
• Updates posted to this page throughout project delivery