compare_cities
ChatGPTCompare the EPA records of several cities side by side. Pass cities as 'City, ST' strings.
Overview
TapWaterMap shows US tap-water quality city by city, using the EPA's own Safe Drinking Water Information System (SDWIS) records. Look up the water systems serving a city, the contaminants and violations on record — with dates and whether the EPA classifies each as health-based — compare cities side by side, and understand what any contaminant is. It's calm and sourced: it reports what the EPA recorded and never gives a safety verdict. Covers about 19,000 cities across all 50 states and DC.
Tools
coverage_stats
ChatGPTWhat TapWaterMap covers: states, cities, total EPA violation records, and the data quarter/date.
explain_contaminant
ChatGPTPlain-English explanation of an EPA contaminant by name or code: the EPA name, whether the EPA classifies it as health-based, and how often it appears in our records. Not medical advice.
fetch
ChatGPTFetch the full plain-English EPA tap-water record for a city id (e.g. 'vt/burlington') returned by
search. (ChatGPT/Deep-Research compatible.)find_cities
ChatGPTFilter/rank cities across the dataset — e.g. cities in TX with open health-based violations, or cities with a specific contaminant. Returns ranked matches.
get_city_water
ChatGPTThe core tool: what the EPA has on record for a city's tap water — the active community water systems serving it, populations, sources, and violations (contaminant, health-based or not, dates, status, level vs limit when recorded). Plain-English, sourced, never a safety verdict.
get_water_system
ChatGPTEPA record for a single water system by its PWSID (e.g. 'VT0005053'): name, population served, source, and violations.
list_state_cities
ChatGPTList all covered cities in a state (with violation counts).
search
ChatGPTSearch TapWaterMap for US cities by name. Returns matching cities with an id you can pass to
fetch. (ChatGPT/Deep-Research compatible.)search_cities
ChatGPTFind covered US cities by name, optionally within a state. Returns counts + the page URL for each.
