Water: A to Zoo

By Star Tribune graphic by MARK BOSWELL and KAREN YOUSO, Photographs by STEVE RICE

Last update: December 1, 2008 - 7:38 PM

OTHER

TERRESTRIAL

ANIMALS AND

HUMAN USES

Fresh water for animal habitats, bathrooms, fountains and drinking water.

'OCEAN WATER' FOR FISH AND SHARKS

Animals that live in water and don't breathe air need a special type of salt water.

Create: Chlorine and other additives are removed from tap water. A manufactured "Instant Ocean" additive, containing 12 salts found in ocean waters, is added. Water is filtered and stored for use when needed.

Renew: Some of the water in the exhibit is sent through a filtering system that removes particulates and smaller biological debris. Ozone bubbles remove any biological contaminants that can harm the fish. Filters are cleaned when they're taken offline in a cleaning process called backwash filtering.

Show: The regenerated ocean water is then heated or cooled as needed, and added to existing water in exhibit areas.

FRESH WATER FOR FISH

Fresh water for fish is different from that used by humans. Chlorine and other additives in tap water can harm fish gills.

Create: The water is filtered and treated to re-create water like that found in Minnesota lakes. Sometimes it needs additional filtration and is held in an aging/holding tank; water is added as needed.

Renew: Some of the water is sent through a filtering system to remove dirt, leaves and microbes.

Show: Water is heated or cooled as needed, and added to the exhibit areas.

FRESH WATER FOR MAMMALS

Fresh water for mammals is different from that used by fish or humans.

Create: Chlorine and other additives in tap water are removed. The water is filtered and treated to re-create the type of water that might be found in lakes. Additional filtration and a holding/aging tank is used; tap water is added as needed.

Renew: A filtration system uses sand, carbon and chlorine to remove everything from dirt and leaves down to the tiniest of microbes. Chlorine is removed again, except for water for beavers, which need some chlorine to stay healthy.

Show: The water is then heated or cooled as needed, and added to the exhibit areas.

Water is needed in vast amounts to keep the animals and plants thriving at the Minnesota Zoo. It starts in aquifers deep under the city of Apple Valley, which turns it into potable water. Entering the zoo's giant water management system, the water is processed to provide the distinctly different types of water needed for saltwater and freshwater mammals and fish, terrestrial animals and humans. And it must be done ecologically. Here's a look at four of the biggest arteries of that system:

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