Background

Growth in southwest Idaho's Boise area spurred the need to improve roadway capacity and safety on Maple Grove Road, from Victory Road to Overland Road. Horrocks provided transportation design services to widen a 1-mile segment, converting a two-lane, rural road into a five-lane urban arterial roadway. Significant improvements to existing drainage and irrigation systems were also made.

Project Details

Horrocks designed a roadway that included two new travel lanes, a two-way left turn lane, bicycle lanes, curb and gutter, and sidewalk. The project also included reconstruction and widening of three bridges and the addition of two Pedestrian Hybrid Beacons (PHBs). To accommodate the widened roadway design, Horrocks designed an urban stormwater system to collect, convey, treat, and infiltrate on-site runoff through seepage beds.

Outcomes

This project was successful in reducing traffic and improving safety and access for pedestrians and bicyclists on this 1-mile segment of Maple Grove Road. The new design also better facilitates access to nearby Molenaar Park and Maple Grove Elementary School. Horrocks worked with the Ada County Highway District (ACHD) to successfully develop a plan for these critical roadway alignments, minimizing impact to existing homes, high-voltage power lines, and irrigation facilities while still meeting operational needs for the 2040 design year in Boise's growing landscape. 

Awards:

WTS International Southwest Idaho Chapter, Innovative Transportation Solution Award, 2021