# Underfoot Water > Underfoot Water is an educational publication about aquifers, groundwater movement, private wells, and the evidence needed to make careful water-testing decisions. Underfoot Water publishes original, long-form guides about Groundwater, wells, and testing made visible.. Every article opens with a concise direct answer, is structured with clear headings and FAQs, and reflects mainstream expert consensus. Health-related content is educational and encourages professional consultation where appropriate. ## Private-Well Literacy - [How Often Should You Test Private Well Water?](https://groundwatergovernance.org/how-often-test-private-well-water/): The U.S. Centers for Disease Control and Prevention says to test private well water at least once every year for total coliform bacteria, nitrates, total… ## Aquifers & Flow - [What Is an Aquifer? Groundwater in Plain English](https://groundwatergovernance.org/what-is-an-aquifer/): An aquifer is a permeable layer of rock, sand, or gravel that stores and transmits enough groundwater to supply wells or springs. ## Full text for LLMs - [llms-full.txt](https://groundwatergovernance.org/llms-full.txt): every article as plain markdown in one file - Each article is also available as markdown at https://groundwatergovernance.org/.md ## Site - [About](https://groundwatergovernance.org/about/): editorial approach and standards - [All articles](https://groundwatergovernance.org/all/) - [Contact](https://groundwatergovernance.org/contact/)