The city's aerial imaging project includes photography with the clearest images yet of the community from above. This photograph shows the intersection St. Michaels and Reid streets, with the high school in the lower left.
This side-by-side shows the high level of detail created by aerial LiDAR (laser) imaging (on the right) compared with IfSAR (radar) imaging (on the left). The view is of the upper reservoir and dam for the city's water supply. The radar imaging has its uses, such as the state's widespread digital mapping initiative across Alaska, but LiDAR produces much more detailed images. Wrangell has contracted for aerial imaging, including LiDAR, of almost 1,400 acres from the north end of the island to south of Heritage Harbor.
For not much more money - less than $10,000 - the city is able to add 411 acres at the north end of the island to an aerial imaging project that already covers 957 acres of downtown, Wrangell's water reservoirs, and land south and east of Heritage Harbor.
It has been almost 20 years since aerial photography of the community. In addition, the project includes LiDAR, an airborne pulsed laser signal that "sees," measures and produces detailed three-dimensional images of the terrain, ground cover and surface characteristics.
LiDAR, which stands for Light Detection and Ranging, is used in right-of-way projects for pipeline and highways, and increasingly for municipal mapping and planning work.
The borough assembly May 11 approved adding $9,425 to the original contract for imaging services to expand the work to include the north end of the island, covering from just north of the state ferry terminal to the airport and over to the turnoff to the golf course.
The original contract for $24,094 covered lands to the south, and beyond Heritage Harbor.
The contractor, Portland-based Elevate UAS, was coming to Wrangell this spring for aerial imaging work of rockfall areas on Zimovia Highway for the state Department of Transportation. The borough was able to piggyback on that work, and in April approved a contract with Elevate for the first 957 acres.
In addition to the water reservoirs and slopes, that area includes aerial photography and LiDAR of "all community development from approximately Blooms Trailer Court across from City Park to north of town up to the intersection of either end of Evergreen Avenue and Bennett Street," borough staff reported to the assembly.
Equipment problems with its drone requires Elevate to return to Wrangell to finish the job - at no additional cost to the city - but it also provided a low-cost opportunity to add the additional acreage at the north end.
"We'd like to take advantage of that," Borough Manager Lisa Von Bargen said at the May 11 assembly meeting, where members unanimously approved the $9,425.
Having detailed LiDAR images will help reduce the cost of future ground survey work, Amber Al-Haddad, the borough's capital facilities director, told the assembly.
The updated aerial photography will assist residents and contractors plan and design their work, said Carol Rushmore, Wrangell's economic development director.
"This new (imaging) system with the drone is pretty incredible," Al-Haddad said in an interview last Friday.
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