How do you figure out if you have fluoride in your water or not?

It looks like a few but not all MUDs and WCIDs add fluoride to drinking water. I’m trying to confirm so I know if I need to supplement fluoride for my 6 month old. This is the website I’m referencing on fluoride: https://nccd.cdc.gov/DOH_MWF/Default/WaterSystemList.aspx. But I’m struggling to figure out which water district we are part of. We live in the Heights – 77008.

Thanks!