Cold Region Hydrologic and Hydraulic Studies

Coldfoot, Alaska

In much of northern Alaska, rural airports are the only form of transportation for food, supplies and emergency life support. In support of maintaining operations at two airports, Michael Baker performed hydrologic and hydraulic (H&H) studies and provided bank erosion solutions.

Holy Cross is located on the west bank of the Yukon River and Walker Slough. Ice jamming floods both channels during the spring breakup. As a result, the highest flood events occur at this time and often threaten the community and airstrip. The current runway faced severe bank erosion due to melting permafrost and erosional forces of the spring breakup flows. Our team analyzed the effects of ice jamming and other environmental considerations to determine the 100-year flood event and ultimately determine a safe elevation for the new runway. The H&H assessment included a historic bank migration, bank stability analysis and hydraulic backwater modeling.

Coldfoot Airport is located adjacent the middle fork of the Koyukuk River. The river was actively eroding the river banks and threatening the runway and airport facilities. We prepared a historic bank migration and stability analysis, flood frequency analysis and hydraulic backwater modeling. Based on the results, we prepared a full civil design package for airport rehabilitation, including new revetment to stabilize the bank, resurfacing of the runway, taxiway and apron and new lighting. During construction, our team assisted with construction support, reviewing submittals, quantities and providing additional engineering for construction changes, including rehabilitation of the existing revetment.