This map shows county medians of 2024 environmental water pH observations from the Water Quality Portal. It describes the available monitoring records; it cannot predict the pH of your tap water.
Observations can come from rivers, reservoirs, wells, estuaries, and other sites. Sampling is uneven, and the map does not show sample counts or site types alongside the medians. Use it to explore those records, not to rank counties or substitute for measurements of your own water.