Lowell Creek Tunnel Seward, AK
eTrac has completed two terrestrial laser scanning projects underground within the Lowell Creek Diversion Tunnel in Seward, AK. Each winter the tunnel is dry and surveyors go underground with the Riegl VZ400 terrestrial laser scanner to survey the changes and upgrades made each year. The annual survey is crucial to understanding this Pre-WWII tunnel and provides insight on upgrades and repairs. The tunnel (known to locals as the “waterfall”) drains into Resurrection Bay passing under the Lowell Point Bridge which is the only access point to Lowell Point, a coastal community populated by fish camps and year round residents. Under the roadway is also the location of the city’s sewage line. In February 2017 and March 2018 our surveyors mapped the half mile long tunnel to account for new changes and any erosion; in 2017 the floor of the tunnel was slanted inwards on each side whereas in 2018 a flush tunnel floor was laid.