I really enjoy dyeing wool and silk, the two main sources of water that I use are city water, from the public library I work at, and my own well water.  It has never occurred to me that if I were to experiment more with natural dyes I should be more mindful of where my water has come from.  The article I linked to below is a font of information about an experiment that some dyeists have undertaken and some of their results.

https://www.wxpr.org/post/science-art-combine-show-waters-different-lakes-produce-strikingly-different-dye-results?utm_source=Mielke%27s+Fiber+Arts+Newsletter&utm_campaign=12ce5e6089-EMAIL_CAMPAIGN_2020_01_16_03_53&utm_medium=email&utm_term=0_1c69f401ff-12ce5e6089-107039657&ct=t(EMAIL_CAMPAIGN_1_16_2020_11_11)&mc_cid=12ce5e6089&mc_eid=92603a0e99#stream/0