Colorado officials say Alamosa’s tap water is safe to drink after they used chlorine to remove salmonella contamination.

The water was declared safe Friday in the south-central Colorado city.

Nearly 390 salmonella cases have been reported since the first instance surfaced on March 7. At least 107 cases have been confirmed and 16 people required hospitalization.

Residents were told to stop drinking tap water on March 19. Health officials confirmed the presence of salmonella later.

Officials began flushing the 50-mile water system with strong concentrations of chlorine on March 25. Residual amounts of chlorine will be left in the water to prevent future contamination.

Officials aren’t sure how salmonella got into the water.