These are two photos of the installation of helical anchors that will support the foundation of the new Staring Lake Observatory. The helical anchors are being used because of poor weight-bearing capacity of the mushy soil on the shore of the lake. We could have used steel or wood pilings driven deep into the ground with a pile driving machine, but the helical anchors are cheaper and require less equipment, and we think are just as good.
The general contractor for the observatory project is Hunerberg Construction. They hired Atlas Foundation to install the five anchors that range in depth from 65 to 84 feet. The anchors are installed using a hydraulic motor on a the arm of a small tracked excavator. The helical anchor lead or head has three “screw-type” 
fins. After placing the head into the ground, 10 foot long shaft sections are added as the hydraulic motor screws the assembly into the ground. The operation continues until the head sinks into firm ground. The number of helicals and their bearing capacity is dictated by the structural engineers calculation of the building size and weight plus a safety factor to prevent future settling or uneven shifting.
We’re now in a position to start seeing above-ground construction. That’s always exciting in a project. I think it’ll be especially interesting in a project like this one. I’ve had a chance to be a part of many different kinds of municipal building projects during my career. Everything from water treatment plants to wastewater treatment plants; from swimming pools to skateboard parks; from airplane hangars to salt storage sheds; from fire stations to fueling stations. But never an observatory. It will be fun to see it take shape over the next few months.
