The 7'-9" walls were typical straight walls, but the 10'-10" inside radius arch between the walls presented some form design challenges. Flex-Form was an obvious choice to form the arch. However, because the inside forms would be inaccessible to a crane after concrete placement, a means to strip and move these forms had to be devised.

To provide the support and mobility required, a framework of Symons Soldier and rolling components was proposed. This system allowed the inside forms to be pulled in slightly, lowered with screw jacks and then rolled to the next concrete pour position.

While moving the outside forms was not an issue, the relatively tight curve of the arch created some other challenges that required modifications because standard pour doors are not designed to accommodate the specified radius. Symons proposed inserting Flex-Form void panels at intervals instead. They provided the necessary openings for concrete placement and vibration, and were closed as the concrete level was raised in the form.