Project Overview
With more than 500 miles of paved and unpaved trails and plowed winter walkways, the Municipality of Anchorage is an impressive outdoor recreation destination. PND helped improve recreational access for Anchorage’s residents and visitors by upgrading approximately 1.5 miles of the popular Tour of Anchorage Trail, replacing three bridges that had been prone to flooding, and adding a fourth bridge on the North Gasline Trail in Far North Bicentennial Park. PND’s design considered the needs of runners, walkers, bicyclists, skijorers, and Nordic skiers, as well as trail grooming equipment and emergency access. PND led civil, geotechnical, structural, and hydrologic and hydraulic (H&H) engineering, as well as permitting, survey, and construction administration services to achieve a project that met our client’s standards and stayed true to the character of Far North Bicentennial Park.
Our Role
- Hydrology & Hydraulics: provided bridge scour and channel design, an H&H report, floodplain analysis, permanent erosion protection, 2D hydraulic modeling, and hydraulic design of riprap scour protection along the creek and trail embankments
- Structural Engineering: designed four bridges for pedestrians, cyclists, and skiers over dynamic streams
- Environmental Consulting: conducted USACE-method wetland delineations; prepared a wetlands report with delineation results, impacts assessment, and mitigation planning; developed a USACE permit application package; and assisted with documenting cultural resources
Designing for Complex Stream Environments
In addition to conducting a geotechnical field program and civil design of the trail improvements, PND evaluated four bridge crossings along Campbell Creek and developed hydraulic and structural solutions suited to stream environments with substantial aufeis, dynamic floodplains, and extensive beaver activity. PND used 2D hydraulic modeling to determine flood levels/extents and assess hydraulics for designing new bridge structures, revetments, and bank stabilization measures that maintained the streams in their existing channels.
We provided wetlands delineation, cultural resources studies, permitting for work in and around anadromous streams, a stormwater pollution prevention plan, and plans, specifications, and estimates. During the NEPA process, several culturally modified trees were identified through consultation with the Chickaloon Village Traditional Council; PND documented the resources and modified the design to avoid impacts. The improved Tour Trail reopened in 2023.
Miles
trail improvements along the Tour of Anchorage Trail
Bridges
replaced or added across Campbell Creek
