Indianapolis Zoo

Humans and dolphins discovered a whole new way of looking at each other at the Indianapolis Zoo. In 2005, the zoo opened up the first, one of a kind, completely submerged, fully enclosed dolphin dome viewing room. The dome sits below 5 feet (1.5m) of water while providing 360 degree views of the pool around it. With a combined weight of 52,200 pounds (23,678 kg), the dome measures 12 feet high (3.7m) and has a 30 foot diameter (9.1m). The dome is suspended 10 feet (3m) from the bottom of the pool and 5 feet (1.5m) from the surface.

The complete dome and tunnel structure resists over 1,000,000 pounds (453.6 metric tons) of pressure that is resting on it while the dome itself holds back over 300,000 pounds (136 metric tons) of water with its 4.4 inch walls (112mm). The entire facility holds 2.3 million gallons (8.7 million liters) of monitored and filtered seawater. This includes a 1 million gallon (3.8 million liter) main performance pool that the dome is in.

The pool itself is 134 feet long x 56 feet wide x 27 feet deep (40.8m L x 17.1m W x 8.2m D). It can hold the equivalent of 100 school busses or six average ranch style houses! Two clear, acrylic tunnels attached to the dome serve as the entrance and exit to the room. Each of the tunnels are nearly 17 feet long x 8 feet wide x 5.6 feet high (5.08m L x 2.4m W x 1.7m H). The walls of the tunnel are 3 inches thick (76mm) to withstand water pressure.

All of the acrylic components were custom cast and bonded using our proprietary bonding method. The dome was designed and constructed with the public in mind allowing them to view the dolphin show and the exhibit from under five feet of water. Before construction began, the dolphins were relocated to a separate holding facility for approximately 9 months. Once this was completed the redesign of the pavilion began. The project was headed by architect Kent Pinaire, the zoo’s manager of special projects.

The process of creating something unique that the world had never seen before officially kicked off on 16 August 2004, utilizing plans created by the architectural firms of Peckham Guyton Albers and Viets, Inc. and Browning Day Mullins Dierdorf Architects, with general contractor Turner Construction. As part of the project, RPT removed an existing structure, refurbished the windows, and built the steel mullions that were to become part of the dome. Workers later poured the concrete for the support pillars of the acrylic panels for the underwater dome room and the steel frame was installed. In January 2005, RPT began installing all 19 acrylic panels required for the dome and the two tunnels. Three cranes were required to lift each of the panels from outside the building into the building and then into the steel frame set up for them in the pool. The project was completed and the pool filled for the grand opening in May when the dolphins were introduced to their new home.