What Is in Indianapolis Water Besides Chlorine?

Citizens states it uses a small amount of ammonia to minimize byproducts of the disinfection process and to allow chlorine to persist longer in the distribution system. The practical effect is a longer-lasting disinfectant residual, which is a safety feature.

Citizens feeds orthophosphate to minimize the possibility of corrosion in customer plumbing. In 2025 the utility sampled 100 homes at the tap in connection with adding the corrosion inhibitor. It is there to protect your pipes, not to treat the water aesthetically.

The groundwater plants aerate and filter to remove dissolved iron and manganese before distribution, and reported iron has stayed below the secondary standard. If you are seeing orange staining on a city connection, that is worth investigating rather than assuming, and on a private well it is a different conversation entirely.

No, and you would not want it to. Fluoride and orthophosphate are added deliberately. Disinfectant residual is a safety feature of the distribution system. Whole-house filtration is typically aimed at chlorine taste and odor and at sediment, with media chosen for the specific target.

Yes, and it deserves stating plainly. The CDC notes that installing a whole-home filter that removes chlorine or other disinfectants can allow more germs to grow in your plumbing. That is a genuine trade-off to weigh, not a reason to avoid filtration outright.

Citizens publishes an annual water-quality report with the treatment description and the measured data by system. It is the primary source for anything about your municipal water, and we would rather send you there than summarize selectively.