A water filter system designed by a Christchurch couple is being touted as a tool that can turn sewage-polluted water into drinking water.

Russell Kelly and his wife Sue, who have 17-years of experience in the water treatment business, have spent four years developing the filter system for third world countries.

Mr Kelly says NASA has given them the rights to use the iodine technology which it developed, and also given them approval to use NASA's logo.

He says the system being launched today gives him the confidence to drink polluted Avon River water.