Tertiary treatments complement primary and secondary treatments. They allow a superior quality of purified water as far as bacteria are concerned to be obtained and thus to protect natural environnement.
NANTAISE DES EAUX INGÉNIERIE offers different types of tertiary treatment:

• Continuous washing sand filter
• Discontinuous washing sand filter
• UV treatment
• Chlorination - dechlorination
• Reverse osmosis
• Ultra-filtration