As part of an agreement with the State of Ohio, the City of Columbus built a massive tunnel to reduce combined sewer overflows and their environmental impacts during flood events. The tunnel project, dubbed OARS, was designed to intercept wet weather overflows that would otherwise empty into the Scioto River in the heart of Columbus and instead carry the flows to wastewater treatment plants.
The 20-foot-wide tunnel runs nearly four-and-a-half miles at a depth of 170 feet and is connected to surface stations via maintenance shafts. Construction officials required Sky Climber’s help to access the largest shaft during several construction phases of installing pipes and bracing for the pipes in and around different areas.
OARS shaft access platform, Columbus, OH
Sky Climber provided a system of permanently-installed rigging equipment for use during construction and for later routine maintenance. The system includes a manned work platform that can be hoisted over a retaining wall and down into the shaft up to 200 feet.
The Sky Climber access system included 14 davit bases with embed cages around the opening of the shaft and 2 movable top rotating davits. The davits were used as rigging points as well to allow the manned suspended access platform to traverse over the 4-foot safety wall before entering and descending into the shaft. The 3-meter platform was powered by Compact air hoists as main travel hoists and separate Compact Air rescue hoists as an emergency rescue system.
In addition to providing the design and equipment for this project, Sky Climber also trained crews on-site in the safe installation and operation of the system.