The Life Support System Facility at the Saint Louis Zoo’s Sea Lion Sound is a national model among U.S. zoos for filtering and saving water.
At this facility, the Zoo’s Life Support Team turns tap water into salt water, changes the pH of the water to counter acidity caused by animal waste and adds binding agents. All this insures that the exhibit’s 250,000 gallons of water meet the highest possible parameters for a safe environment for the California sea lions and harbor seal. They also keep the water clear for the visitors to see the animals enjoy their award-winning habitat.
Filtering exhibit water, reclaiming waste water and again filtering it for reuse through these efficient new Sea Lion Sound systems use 11 million fewer gallons of water each year than was used at the previous sea lion exhibit. Thanks to this system and other operational improvements, the Zoo reduced water use by 4.1 percent in 2013, using 15.5 million fewer gallons than in 2012.
Through a network of computers, the Life Support Team can remotely control pumps, valves, water flow and water levels; they can even change settings from their tablets while working away from their desks or from home in case of emergency. With this automated system, they also monitor and control filter operations and water temperature and quality to ensure the appropriate environment for the animals.
Process Begins Underground
The process begins with tap water, which is transformed by moving it into one of five underground basins where sea salt is added to maintain the marine environment.
Once the salt water enters the main pool, the automated control system drives the filtration process, channeling the unfiltered water through miles of underground piping and then pushing it through seven, 8-foot wide by 10-foot high fiberglass sand filters to thoroughly clean the water.
Once filtered, the water is then injected with ozone gas to disinfect it as it enters a contact chamber. It then flows down through a deaeration tower to strip the last of the ozone gas bubbles away before it goes back to the pools.
“Injecting ozone into the filtered water allows us to use only a minute amount of chlorine to ensure water purity,” said Zoo Life Support System Supervisor David Jarvis. “We use less chlorine than you would normally find in your tap water just to help us control algae.”
The team collects waste water from the sand filter backwashes and by vacuuming the exhibit pools. “All that water then goes into the underground collection basins,” Jarvis said. “This water would normally go to the sewer system if we did not reuse it by processing it through low waste bead filters. About 200 gallons per backwash is all that goes into the sewer system, as opposed to around 5,600 gallons for conventional systems.”
“This facility is a major factor in our ability to cut our water use, but we realize that you cannot change what you do not know so monitoring and tracking are key to reducing our water use,” said Wanda Evans, Sustainability Coordinator at the Saint Louis Zoo. “That’s why we have installed 11 water meters in areas where we use the most water. We also began a multi-year process to install point-of-use meters at each Zoo building and exhibit. In addition, we have placed several rain barrels across our campus to capture water. We have also worked to fix leaks and investigated areas where there is water loss. Finally, we are educating staff and visitors about the need to conserve water with educational signage and through other programs.”
World Water Day
World Water Day has been observed since 1993 when the United Nations General Assembly declared March 22 as a day to promote clean, sustainable water and aquatic habitats and focus attention on critical water shortages and poor water quality across the globe.
Sea Lion Sound
Located in the center of the Zoo, the 1.5-acre, $18 million habitat and arena for California sea lions and a seal includes two state-of-the-art marine mammal exhibits.
Enterprise Rent-A-Car Family Sea Lion Landing features a spectacular 35-foot-long underwater viewing tunnel, where visitors can see animals swimming around them. This spacious, year-round outdoor pool and habitat features varying depths of water and rocky outcroppings.
The Lichtenstein Sea Lion Arena includes an 811-seat amphitheater, the large Ann Lux Family Stage, a 40,000-gallon see-through pool, a rock bridge extending into the audience and a high diving platform and slide — all designed to show off the sea lions’ natural abilities.
The arena is home to the First Bank Sea Lion Show. Sea Lion Spring Training shows began March 15 and run from 1 and 3 p.m. daily through March 30o. Timed tickets are $2 per person. Children under two are free.
Opening Day for this season’s show is April 5 with performances on Saturdays and Sundays only through May 25. Daily summer shows run Memorial Day through Labor Day, May 26 to Sept. 1. Show times are 10:30 a.m., 1 and 3 p.m., with an additional show at 5 p.m. on May 26, July 3 and on weekends and holidays in summer. Timed tickets for these shows are $4 per person. Children under two are free.