How did you narrow it down to the water? Having the same issue with the past several batches. Have poured out three of the last four. Since then I have changed something with each batch. I've used Poland Spring, Kroger Spring and Well water from the tap. I bottled a Cream Ale all grain batch...
I'm having the same issue with a batch I brewed. I was leaning toward it being from either the Iodophor not being rinsed out of the bottles and caps or from having a very slow fermentation (it took over 3 days for it to start because of the cold).