Interstate A3
Overview
Interstate A3 follows Alaska State Route 1 (Sterling Highway) south from I-A1 (5th/6th Streets) east of Downtown Alaska to Kenai Spur Highway in Soldotna. The route initially follows the couplet of Gambell Street south 1.11 miles and Ingra Street north 1.09 miles. Sterling Highway commences south from the couplet as an eight lane arterial leading onto a freeway 8.88 miles to E 154th Avenue near Potter Marsh.
The remainder of Seward Highway south to Sterling Highway is a two lane highway with several sections of passing lanes. SR 1 straddles the east banks of Turnagain Arm to Girdwood and Portage. Hooking west across Placer River Valley, Seward Highway continues into Kenai Peninsula borough, where it gains elevation.
I-A3 and SR 1 separate from Seward Highway for Sterling Highway west at Tern Lake. Seward Highway spurs south to Seward as SR 9 while Sterling Highway leads SR 1 west to Cooper Landing and along the Kenai River to the Mystery Hills. Sterling Highway expands into a four lane boulevard west from Sterling into Soldotna.
Route Information
Source: December 31, 2021 Interstate Route Log and Finders List
Average Annual Daily Traffic
Source: 2020 Average Annual Daily Traffic County, Alaska DOT&PF GIS Shapefile
History
Seward Highway south from Anchorage to Sterling was dedicated on October 19, 1951. Initially referenced as the Seward-Anchorage Highway, the 128 mile long route also connected Anchorage with Sterling Highway on the Kenai peninsula. Reconstruction continued along sections of old Seward-Hope Road between Seward and mile post 58 into 1952. The section from Girdwood to Anchorage was under contract by December 1951 for paving.1
Serving as the primary connection between the Seward Highway and Glenn Highway, Gambell Street was paved in 1960. The 1980 Anchorage, Alaska Metropolitan Area General Plan published in 1961 proposed a link between the two highways along an expanded Orca Street to the east, between Fairview and Merrill Field. However following the 1964 Good Friday Earthquake, the alignment along Orca Street was dropped from plans due to high costs. Instead city planners proposed routing traffic north along the couplet of Gambell and Ingra Streets and east via 5th/6th Avenues.2
The Alaska Department of Highways opened bids for construction of the couplet along 5th/6th Avenues between Gambell and Medfra Streets in Anchorage on March 28, 1966. The project included grading, drainage and paving along 0.42 miles of city streets.3 A low bid of $1,642,494 was submitted for construction of the Ingra-Gambell Couplet between Northern Lights Boulevard and 5th Avenue by S.S. Mullen, Inc., of Seattle. The contract let by January 12, 1966 included grading, drainage and paving along 1.648 miles of roadway along with the installation of traffic signals an street lights. The state estimated $1,466,769 for the work.4
Photo Guides
North End – Anchorage
North at
South at
South End / Kenai Spur Highway – Soldotna, Alaska
South at Kenai Spur Highway
North at Kenai Spur Highway
Kenai Spur Highway at
Sources:
- “Road Commmission Reports on Activities During Past Year.” Fairbanks Daily News-Miner (AK), December 27, 1951.
- “Opinion: Why planners routed a highway through Anchorage’s Fairview neighborhood.” Anchorage Daily News (AK), May 25, 2023.
- “Calls for Bids for Anchorage City Streets.” Fairbanks Daily News-Miner (AK), March 15, 1966.
- “Anchorage Couplet Contract Let.” Fairbanks Daily News-Miner (AK), January 12, 1966.
Page updated September 25, 2023.