I'm expecting the reaction you mean is some sort of color change that can be easily seen with the naked eye. To put it as simply as I can, you can't expect such a reaction, with the levels of chlorine usually found in municipal tap water, much less likely for chloroform levels. They do sell visible, colormetric tests, for pool chlorine or other disinfecting levels of chlorine.
Failing that, there are laboratory tests for trace levels of chemicals, that will test water for a fee. But they work on contract with companies, they simply won't take your tap water because you're curious. Not at any price. Which will be a high one, if they're under contract.