There is a high concentration of sulphur in the Central Florida water supply. We have noticed it as far North as Lake City. Over the years, Disney has done a pretty good job with installing filters to improve the taste of the water.
I had been to Disney as a toddler in '71 and '73 and stayed at off-site campgrounds with really swampy sulphur water. I returned 19 years later for my honeymoon in '92. We stayed off site, and DH about gagged when he tried to brush his teeth. "OMG, what is wrong with this water?" I tasted and said, "oh yeah, the water is awful here, I forgot." We now bring bottled water for everything and order soft drinks in the parks with no ice.
We live in Alabama, and the tap water is generally good here, so we notice bad water.