Water on the Space Station

Shuttle pilot Terry Wilcutt with 7 contingency water containers destined for the space station Mir.

Before recycling can begin, there has to be some water to start with.

"We have plenty of water on the Space Station now," says Jim Reuter, leader of the ECLSS group at the Marshall Space Flight Center. "The Russian module Zarya is packed with contingency water containers (CWCs) that were carried over from the Space Shuttle during assembly missions earlier this year. They look like duffle bags and each one holds about 90 lbs.

"But it's expensive to ferry water from Earth," he added. "We have to recycle. There's already a Russian-built water processor in orbit that collects humidity from the air. Here at Marshall we're building a regenerative system that will be able to recycle almost every drop of water on the station and support a crew of seven with minimal resupplies."

The ECLSS Water Recycling System (WRS), developed at the MSFC, will reclaim waste waters from the Space Shuttle's fuel cells, from urine, from oral hygiene and hand washing, and by condensing humidity from the air. Without such careful recycling 40,000 pounds per year of water from Earth would be required to resupply a minimum of four crewmembers for the life of the station.

Not even research animals are excused from the program.

"Lab animals on the ISS breath and urinate, too, and we plan to reclaim their waste products along with the crew's. A full complement of 72 rats would equal about one human in terms of water reclamation," says Layne Carter, a water-processing specialist at the MSFC.

It might sound disgusting, but water leaving the space station's purification machines will be cleaner than what most of us drink on Earth.

"The water that we generate is much cleaner than anything you'll ever get out of any tap in the United States," says Carter. "We certainly do a much more aggressive treatment process (than municipal waste water treatment plants). We have practically ultra-pure water by the time our water's finished."