Nevada has BAD water. Do the restaurants filter the water they serve to customers?

Two of Nevada's largest gambling Meccas, Reno and Las Vegas, are in the top 5 US cities with the worst drinking water. I learned of this sobering fact after having spent several days in Reno eating and drinking with relish and gusto. After returning home, I plopped down in front of the TV and turned on the news. After a few minutes, I heard something that made my stomach turn! The water in Reno and Las Vegas was so bad it made the evening news! I jumped on my laptop and and found a national water testing agency: The Environmental Working Group. Their report verified what I had heard on the news and listed all the poisons and chemical toxins in sordid detail! My mind flashed back to Reno where mere hours ago I sat in a restaurant. Critically, I relived the moment a waitress placed what appeared to be a sparkling clean gl of water and a cup of Joe on the table. There were no warning labels on the gl or cup...there were no signs urging customers to beware of ingesting liquids here due to carcinogens, pesticides and arsenic known to be floating in our water! Mandatory filtration and reverse osmosis should be the minimum water treatment requirements for hotels and restaurants , especially where testing has shown problems that could have dire consequences on the health of innocent people. Now, I return to my original question: Do restaurants gamble with the health of their customers by refusing to take measures to ensure that we are not exposed to chlorinated, toxic tap water after we leave home and enter their domain!