Marsh Creek, LLC

Juneau Area Telecommunications Upgrades

Juneau area projects include five road accessible sites and two helicopter accessible sites. Contracting mechanisms for these projects included competitive and sole source awards. Work at these sites consisted of constructing/improving decking for placement of BTS cabinets, upgrading communications and electrical systems for the site and the BTS cabinets, adding an ice bridge, installing new antennas and coaxial cables, and upgrading grounding systems. Working on the helicopter accessible sites rquired moutain-side and mountain-top tower work at elevations up to 1,400.

New Self-Support Towers and Monopoles

In the late fall and early winter of 2008 Marsh Creek constructed two self-support towers (120 and 180 feet) using concrete pad and pier, as well as helical pile foundations. Upon project award and receipt of geotechnical investigation results, a foundation redesign analysis was performed. One site (Tern Lake) exhibeted high groundwater and low freeze penetrations while the second site (Moose Pass) exhibited high groundwater, low freeze penetration, and heaving sands (soils that can liquefy during an earthquake). Marsh Creek’s redesign of the tower foundations enabled us to install a concrete pad and pier foundation without impacting groundwater at Tern Lake, and use helical piles at the Moose Pass site to provide a foundation suitable for heaving sands. The foundation redesisign allowed the acceleration of the construction schedule, meeting the clients need to have the towers in place by year end while also saving them an estimated $80,000 at each site.

Anchorage and Ketchikan Rooftop Sites

Marsh Creek fabricated and installed custom platforms to house base transceiver station (BTS) cabinets at a site in Anchorage, and refitted a penthouse room to house BTS cabinets at a site in Ketchikan. For both sites, coaxial cables were protected using cable trays. Antennas and coaxial cables were grounded on building steel and the BTS cabinets and platform/room were independently grounded. Electrical supply to the installed BTS cabinets was connected using existing building capacity. Additional telecommunications lines (T1 lines) were extended to the building by the local area provider and connected to the BTS cabinets. Marsh Creek also coordinated building and zoning permits and inspections.

Mountain Top Tower Construction

Marsh Creek constructed a new 35-foot tall self-supported tower on a mountain-top 17 air miles from Juneau. The tower was constructed on individual concrete piers each anchored 8 feet into bedrock. To construct the piers, concrete trucks were barged to a nearby cove and then concrete was ferried to the site using two helicopters, each with a 1/3-cubic-yard bucket, allowing for "continuous" concrete placement. Tower erection was accomplished by use of a helicopter to lift and place tower legs individually. In addition to constructing the tower and installing antennas, Marsh Creek constructed supports for two 20-foot equipment shelters and installed various support structures, including a helipad, propane tank supports, work/storage platforms, and walkways. Eight 500-gallon propane tanks were placed and secured for use as the on-site fuel source. During construction Marsh Creek remained onsite in a self contained camp on the mountain, reducing costs for helicopter support services and limiting weather delays.