Campbell Creek Trail Crossing at Lake Otis Parkway

Student Members: Logan Curtiss, Mark Cosby, Ani Batbayar, Jesse Batac

Faculty Advisors: Scott Hamel, Ph.D, P.E., UAA

Project Mentor: Chris Post, P.E., Marcy Hensch, Design Engineer., Alaska DOT&PF

Client: Aaron Hunting, P.E., Alaska DOT&PF

Abstract: Campbell Creek trail is a 7.5-mile-long trail that serves as a vital artery for bicyclist commuters and recreationists in Anchorage. The Campbell Creek Trail crossing at Lake Otis is the only at-grade crossing in the entire trail system resulting in conflict points between bicyclists, pedestrians, and passenger vehicles. With the area’s increasing urbanization and use of the Campbell Creek Trail, an improved crossing of Lake Otis Parkway is needed. The Alaska Department of Transportation and Public Facilities (DOT&PF), in cooperation with the Federal Highway Administration (FHWA), proposes constructing a grade-separated crossing of Campbell Creek Trail Crossing at Lake Otis Parkway. The proposed project includes completing an alternative study of options for a grade-separated crossing of Lake Otis Parkway near 47th Court.

Alternative Analysis and Methodology: Our firm, B&C Engineering, Inc., conducted an analysis of seven alternative options provided by the Alaska DOT&PF for the project. During the analysis, three alternatives were found to be infeasible due to the high groundwater levels in the borehole data provided by the Municipality of Anchorage. As a result, the proposed tunnel crossings were found to be unconstructable. To evaluate the remaining alternatives, we utilized a decision matrix.

Preferred Alternative: The preferred alignment (C3) will not incorporate a new pedestrian bridge crossing Campbell Creek and instead utilize the existing crossing when connecting back into the existing trails. The preferred alignment will cross Lake Otis Parkway at a skew creating an approximate bridge span of 230′. This bridge will incorporate equal width of travel as the proposed new trail sections to provide an increase in pedestrian flow. In addition, this bridge will utilize Mechanically Stabilized Earth walls (MSE) substructure walls east and west of Lake Otis in order to construct on undeveloped land.