An Overview of Stream Restoration Activities Along the Trans-Alaska
Pipeline
&
Lessons Learned from Stream Restoration Activities Along the TransAlaska Pipeline
Christopher H. Roach1 and MacNamara C. Shoulders 2
Twelve streams have been restored along the Trans Alaska Pipeline in association with
maintenance activities during the 2000, 2001, and 2002 seasons. This paper describes the site
conditions, assessment, design, construction, performance, and lessons learned from these
projects.
A natural channel design methodology was used, which involves determining the dimension,
pattern, and profile of a stable reference reach for the associated valley type and stream type and
emulating those characteristics in the design reach. Channel controls included a combination of
in-stream rock structures and re-vegetation for bank protection and grade control. Approximately
200 in-stream rock structures have been constructed including rock vanes, J-hook vanes, and
cross vane weirs. The work involved projects on 4 distinct stream types based on the Rosgen
Stream Classification System: step-pool (A stream type), riffle dominated (B stream type), rifflepool (C stream type), and sinuous (E stream type). Climatic regimes varied, including glacial fed
coastal streams, high bedload alpine streams, debris torrent streams on alluvial fans, and
streams in the arctic and sub-arctic. Three unique projects were implemented to convert braided
channels on alluvial fans to stable single thread channels. The channel conversion approach has
proved successful in controlling the position of the streams at the pipeline crossing while
maintaining sediment competence and a stable channel dimension, pattern, and profile.
Biological sampling of the restored reaches has been done by the Alaska Department of Fish &
Game.
1
Engineering Consultant, 3121 E. 112th Ave., Anchorage Alaska 99516
Ph. (907) 677-0645, Fax (907) 677-9609, e-mail chroach@alaska.net
2
Fisheries Biologist, Alyeska Pipeline Service Company, Fairbanks, Alaska 99706
Ph. (907) 787-7910, e-mail shouldersmc@alyeska-pipeline.com