Building a Turnagain Arm Bridge: A Feasibility Study ENGL 212: Technical Writing Bryce Eckroth

Overview Introduction Criteria Methods Research Results Conclusions Recommendations

Introduction Examined the feasibility of constructing a bridge spanning the Turnagain Arm from Anchorage to the city of Hope. Researched public safety statistics along the Seward Highway corridor that this proposed bridge would circumvent to determine project need. Determined economic, public safety, and environmental effects that the bridge would have on South-central Alaska. Identified if the proposed Turnagain Arm Bridge Project is environmentally and economically feasible.

Feasibility Criteria Would the construction of a bridge spanning Turnagain Arm from Windy Pt. to the town of Hope be financially and physically possible? Would the construction of this bridge project effectively mitigate risks to Seward highway users by skipping 60 miles of the current route? Is there a current need for reduction in risks? Would there be any significant environmental impacts created by the construction of this project?

Methods Created & disseminated a questionnaire, in which participants were asked about: demographics, commuter habits along the Seward Highway South of Anchorage, interest/ feelings about a proposed bridge spanning the Turnagain Arm, and effects of such a bridge on Kenai Peninsula economy, the environment, and public safety. Reviewed similar construction projects across Alaska. Focused directly on feasibility studies & reports of a similar bridge spanning the Knik Arm. Analyzed AK Department of Transportation & Public Facilities statistics regarding commuter public safety along the Seward Highway along the Turnagain Arm.

Methods Reviewed Environmental and geological reports of a highly similar report to determine effects of this bridge on the environment and whether or not it could physically be built. Reviewed economy statistics, figures, and projections of South-central Alaska Economies.

Research Results Physical Aspects and Economics of Construction: Quaternary geology of the Turnagain Arm is conducive to building such a bridge. Highly similar Knik Arm Crossing project cost estimated at $650-$750 million dollars, with a roughly $1 million per year cost of operation. Strong population growth rate of 1.72% per year has South-central Alaska’s population growing by over 50% in the next 25 years. Study conducted shows public interest in proposed bridge’s economic benefits.

Research Results Physical Aspects and Economics of Construction “Do you think lower Kenai Peninsula economies such as Seward, Soldotna, and Homer, would benefit from this bridge’s construction?”

Research Results Risk Mitigation From 2001-2007, 121 vehicle crashes occurred along this stretch of the Seward Highway resulting in fatalities or major incapacitating injuries. Challenging road conditions are present due to the physical topography, weather, and variety of user groups. Average vehicle trips sometimes exceed 16,300 vehicles per day, cramping this dangerous stretch of 2-lane highway. Primary research supports this popularity. “How many times per month do you travel on the Seward highway South of Anchorage?”

Research Results Environmental Impacts Similar bridge construction effects on Cook Inlet Beluga Whale populations has been shown to be not detrimental to normal feeding or migratory routes. Sediment displacement or erosion from the bridge’s bridge supports would be expected to be negligible. Mainland connections of the proposed bridge would be spaced so as not to interfere with shoreline migration routes of salmon and smelt species. Dramatic figures of carbon footprint reduction will be realized due to fuel consumption savings with the bridge’s use. A similar bridge projected into the year 2025 totes a net savings of approximately 6.2 million gallons of fuel and over 66,000 metric tons of carbon dioxide by Anchorage commuters.

Research Results Environmental Impacts Public opinion is in favor of infrastructure development in Alaska. Pie slices 1 and 3 represent the majority of survey respondents who thought that bridge projects like the Turnagain Arm project could be constructed to be harmonious with the environment.

Conclusions The data from the geological surveys, economic analysis, population studies, and review of KABATA KAC construction cost estimates indicate that building a bridge spanning the Turnagain Arm could be both physically and financially possible. AKDOT&PF highway safety studies indicate there is a need for reduction in risk to commuters on the Seward Highway. Environmental impact studies conducted on a similar project scope elsewhere in the state of Alaska indicate the construction of a bridge such as that proposed across the Turnagain Arm would not negatively impact the surrounding ecosystem. That, combined with an additional reduction in carbon footprint over the bridge’s lifespan would make the bridge environmentally feasible to construct.

Recommendations An additional study be conducted researching the effects to public safety of bridge construction circumventing dangerous stretches of highway. A more comprehensive questionnaire be disseminated to a larger group of Seward Highway commuters in order to make a precise determination on their feelings regarding bridge construction, current Seward Highway public safety statistics, and toll road use. The Alaska Legislature designates a board similar to the Knik Arm Bridge and Toll Authority which centers on building a Turnagain Arm toll bridge.