When the City of Caldwell advanced the Lake Lowell Pathway to extend its multiuse trail system, it faced the challenge of delivering a new alignment that safely crossed a wide state highway and minimized right-of-way impacts. B&N was selected to develop plans, specifications and cost estimates for approximately one mile of new shared-use path, including a grade-separated pedestrian undercrossing at the junction of SH-55.
The project required careful coordination across multiple disciplines and agencies to support an accelerated schedule and ensure compatibility with both state and municipal requirements.
Multidisciplinary Design and Agency Coordination
As the prime consultant, B&N provided roadway design and modeling, structural design for major retaining walls, electrical and lighting design, and civil and site grading plans. The project involved close coordination with the Idaho Transportation Department (ITD), subconsultants to design the pedestrian underpass and utility stakeholders to address design constraints and maintain the project schedule.
Because the project spans two different agencies, B&N prepared two separate plan packages. The team applied its knowledge of the federal aid process to meet ITD requirements while drawing on municipal experience to align with the city’s objectives and priorities.
Utility and Drainage Solutions in a Constrained Corridor
Utility coordination was a key challenge. In some locations, relocations were required, while in others B&N adjusted the pathway alignment to avoid impacts, including routing the path behind an existing pole line. The corridor’s proximity to irrigation ditches introduced additional drainage constraints, requiring stormwater from new impervious surfaces to be captured, treated and discharged separately from irrigation flows.
B&N addressed these constraints by designing parallel drainage ditches and infiltration basins, providing effective stormwater management while protecting adjacent irrigation infrastructure.