Just like anything else...if it's in excess, it will be harmful and even toxic!

For your own peace of mind, you should attempt to peruse all points of view and scientific determinations.

Here is a blatant water filter 'advertisement.'
www.healingdaily.com/detoxification-diet/water-filtration-systems.htm

The accompanying dissertation on chlorine, contains some basic inaccuracies. Some people hold back essential data, so as scare others into buying certain products.

Chlorine's reactive stages in oxidation, do produce halomines and then trichloromethanes. This is the NATURAL oxidation evolution, up until breakpoint. At that stage, all ammonias etc, have been oxidised, thereby rendering a state of no taste, colour or smell.
At that stage, one can further 'polish' the water, by filtering with activated carbon.
The above process, is exactly the manner in which all soft drink, beer, and other drinks manufacturers, process their make up water.

www.lenntech.com/water-disinfection/disinfectants-chlorine.htm

I was in the industry for over 20 years. I was involved in the design, manufacture and installation of water treatment, sewage treatment, industrial effluent reclamation plants and chlorine generation equipment.

Over and above, we worked in accord with our local subtropical fruit department and the Riverside University in the US, regarding our implementation of Xppm of Cl2 residual on crop spraying. The research regarded the efficacy in the destruction of nematodes in soils.

I think I might know a little more than you do, on this subject.