NV5 - Pelandale

SR-99 Pelandale Avenue Interchange

NV5 provided full suite management services for this $31 million interchange improvements project. The project demolished the existing three-lane Pelandale Avenue overcrossing spanning State Route (SR) 99 and replaced it with a new six-lane overcrossing; built new interchange ramps to connect SR-99 with Sisk Road and Salida Boulevard via new on- and off-ramps with signalized ramp intersections; built a new SR-99 on-ramp bridge grade separation on driven concrete pile foundations; built a northbound auxiliary lane on SR-99 between the new SR-99/Pelandale Avenue interchange and the existing SR-99/SR-219 (Kiernan Avenue) interchange; built merge lanes on SR-99 on the south side of the new Pelandale Avenue interchange; and features a new decorative architectural entry walls.

The project was successfully completed on schedule, on budget, with no claims.

This project involved several major traffic changes which included detours, temporary signalization, and temporary striping. Public outreach and community meetings were held to make these transitions as smooth as possible for the public. Building involved new traffic signals at four intersections; new pavement, including replacement section in existing intersections; multiple retaining walls (both standard Type 1 and MSE designs); drainage basins and drainage systems; driven concrete piles; and extensive utility relocations on Salida Avenue.

After the contractor implemented traffic handling plans for Stage 3 of the project, our team observed considerable backup at the Sisk Road/Pelandale Avenue intersection and the Pelandale/SR-99 off-ramp. This area provides access to local businesses and is a heavily traveled connector between communities on the east and west sides of SR-99. At the request of the City, the contractor was asked to accelerate Stage 4 of the project in this area to alleviate the congestion and backup. The accelerated stage estimate was in excess of $55,000. The NV5 team recommended that a phase at the signal in both directions be eliminated and that designated left turn lanes be utilized as combined through-left lanes. The NV5 plan entailed one night of restriping, moving signal heads, and coordinating intersection timing operations with the City. The cost was $6,000, saved two months of accelerated work, relieved the backup on northbound and southbound Sisk Road and SR-99 northbound off-ramp, and minimized inconvenience to the public and business enterprises, in particular during the holiday season.


Modesto, CA


City of Modesto


Key Facts

Project Cost $31M