Making functional changes with Roundabouts in the City of Galt
At a glance
The City of Galt was looking to modify the aging State Route 99 interchange due to road congestion and the anticipation of a growing population raised concerns for the City. At the same time, the California Department of Transportation (Caltrans) was looking to add pedestrian safety and Americans with Disabilities Act (ADA) upgrades to the interchange to meet the needs of the community. The mission was to meet growth needs of the community while ensuring the safety of citizens.The challenge
The City faced numerous challenges in completing the project, including:
- Skepticism from local agricultural businesses and residents
- Economic challenges and limited funds
- Newer intersection concept needed more review and approvals
- Only one quadrant of the interchange was within city limits
- Several projects were already in progress, such as construction of a large retail store, freeway rehabilitation and pedestrian improvements
- Lack of a water source on the west side of the freeway
- Limited alternative access to existing businesses during construction
Our response
We developed an approach to place roundabouts at each intersection, increasing traffic capacity and providing the accessibility features; addressing the needs of pedestrians while eliminating the need to replace the over-crossing.
To gain the trust of stakeholders regarding their vehicles' ability to navigate the roundabouts, our team implemented a strategy of conducting thorough public outreach and targeted meetings. Our team prepared a scaled exhibit of the roundabouts with cars, buses and semi-trucks to show people how the new construction would work and demonstrate that large vehicles could navigate easily. This eased the public’s concern.
GHD and The City also worked with Caltrans, Sacramento County and local Developers to coordinate construction and share in funding. To address the lack of water for landscaping, a dry landscape theme using artificial turf and coloured glass stones was added to the west side of the freeway to address the lack of a water source.
The review of the budget revealed further cost savings could come from partial and complete closure of the interchange for a short period. A detour plan was developed, and the City of Galt and the Construction Manager reached out to surrounding residents and businesses to inform them of the closures.
The impact
The roundabouts positively impacted the quality of life for pedestrians who can now cross safely and were previously not accommodated for. The new intersections created a calming effect on traffic, incorporated landscaping and artwork, created pedestrian connectivity, had a minimal impact on the existing community and created a sense of place in the city. Existing facilities, including the local parking and Caltrans maintenance area, were also enhanced thanks to the roundabouts.
The overall modifications represented a new approach to transportation planning and designing of interchanges by leveraging the traffic capacity of roundabout intersections.