Township gets water from several wells

So my local municipality gets their water from several wells of varying depths in and around the borough. I was thinking about sending a sample away for a water report, but how do I know if im gettiing the same water a month or year from now. Anyone out there work for a water company or borough? When multiple wells are tied into a water source, are they commonly pumped at the same time or alternated? Just looking for a place to start looking at water chemistry.... up until now ive just been using tap water with treated with campden and hoping for the best.

You have a few options depending on how variable the water that comes out of your tap is. If all the wells produce low mineral content water then it doesn't matter which well you are drawing from. If your neighborhood gets its water from one well while other wells serve other neighborhoods then you are only dealing with variations in the well you are drawing from. Water from all the wells is pooled then you won't have much variation.

I'd suggest either a chat with the supplier as to how your town's water is distributed and as to how much variation you could expect. If you can't get a satisfactory answer that way then start measuring the hardness and alkalinity using kits or the procedure described at http://www.wetnewf.org/pdfs/measuring-alkalinity.html. These two parameters won't give you the complete picture but if they are stable over the year it is likely the rest of the parameters are too and conversely.

The ultimate solution is to install an RO system which you may or may not wish to do anyway depending on what's in your water. In removing nearly all the ions RO systems also remove nearly all the variation.

Yeah... I was thinking I'd need to do some more legwork to see how the water is distributed. I checked the locations of the wells and they're all pretty much within the footprint that would be serviced by the holding tower. The geology is pretty consistent through the well network so I might expect similar water regardless of what well is pumped, though two wells are on the other side of a creek.

I can't see myself going with RO water since I've been making great pale ales and IPAs with my current water... which make up the majority of beer I drink. I figure I'll just supplement with salts and/or di water depending on my water report for other styles. It would be nice to know I'm getting a consistent water profile throughout the year though.