Bollinger Canyon Iron Horse Trail Bridge Overview

(San Ramon, CA) In the fast growing city of San Ramon, CA, the influx of population has led to more people using the road networks and pedestrian infrastructure in the city. One such key connector of the city is the Iron Horse Trail. The trail previously had people have to cross over large roads due to its perpendicular nature to some of the larger roads in the city. In order to combat this problem, the overcrossing bridge at Bollinger Canyon Road was planned and constructed.

The Iron Horse Trail is a flat, paved trail that spans around 32 miles from the city of Concord to Pleasanton. The trail would force users to cross a 6-lane arterial Bollinger Canyon Road in order to continue across the trail. This posed a severe danger to the pedestrians and cyclists using the paved trail. Included in a plan with several other locations where the trail had to cross over arterial roads, several overcrossings were planned in the cities of San Ramon and Dublin. 

The design of the bridge gives it a modern, simplistic feel. The bridge is a steel cable-stayed bridge which is supported using precast deck panels. The cable-stayed component of the bridge means that it is held up by a group of diagonal steel cables. This differs from a suspension bridge because cable-stays have cables going from a point on the bridge to the towers. A suspension would have cables going from tower to tower. Precast deck panels are used in order to avoid having to cast the whole entire deck on-site and instead make it in panels. 

This project helped greatly improve walkability and bike accessibility in San Ramon. The bridge helped connect walking traffic from the southern neighborhoods to City Center and Central Park. Along with a decrease in car dependency for shorter trips, safety was greatly increased at the location. The ability to cross without needing to be at the same tier as a multi-lane arterial meant there were less hazards to pedestrians. Along with this, ADA accessible ramps along the ends of the bridge helps make this bridge usable by all, particularly for the senior center located adjacent to the bridge..

All in all, this bridge was the result of a call to safety and a desire for increased walkability in the city. The ability to connect neighborhoods and increase the safety of public areas through this bridge shows how civil engineering and urban planning go hand-in-hand in developing the cities and neighborhoods that we reside in.