Well, actually here is what I would do. No one likes to hear the sickness that might be involved, especially if you remind them, that their children have been drinking it. Do you know how long people/children have been drinking the water? Can you find out the short term results from it? Even if you have to go to a doctor and ask, do it. Then you find out the long term results from their children drinking it; and pregnant women drinking it, how it effects the unborn child; also, include how it effects the sick people with lowered immunity systems, and the aged people. Do your homework. I would do it because I hate to be shoved around. I would make sure the community realizes your results. Was this the same water that supplied the schools water fountains? The same water people filled up their swimming pools with? Took baths and showers in? Watered there gardens with? I wouldn't let myself be walked on.
The results of the metal tests they had taken should be public record.
Since this happened once, and because of the way I am, I would make sure I had this so-called, approved water container on hand. Just because.
Oh, and also, Eric, if you consider fighting this, find a lawyer whose kids have been drinking the water, too.