{"schema_version":"1.2","pwsid":"WI2670120","system_name":"WEST BEND WATERWORKS","city":"WEST BEND","state":"WI","population_served":31752,"source_type":"GW","summary":"WEST BEND WATERWORKS serves approximately 31,752 people in WEST BEND, Wisconsin. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 1 contaminant has been measured above federal EPA standards (MCL) and 6 exceed health-based guidelines. The most significant finding is PFOA (Perfluorooctanoic Acid) at 0.0065 ug/L, which is 1.6x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2003 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2003-05-22","end":"2026-04-06"},"contaminants_tested":139,"contaminants_detected":27,"exceedances":1,"guideline_exceedances":6,"contaminants":[{"name":"Chlorine (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":0.61,"unit":"mg/L","sample_date":"2026-04-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA MCLG","epa_mcl_value":4,"status":"below_limits","detection_limit":null},{"name":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.78,"unit":"mg/L","sample_date":"2026-03-11","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA 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Not a current MCL."},"well_counts":{"active":9,"retired":2,"facilities_synced_at":"2026-04-11T13:48:07.246Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":{"value":0.087,"compounds_used":["PFHXS","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":0.85,"hbwc_ng_l":10,"ratio":0.085},{"code":"PFBS","value_ng_l":3.9,"hbwc_ng_l":2000,"ratio":0.002}]},"tthm_lraa":[{"monitoring_point":"system_wide","value":20.67,"unit":"ug/L","quarters_used":["2021Q3","2023Q3","2024Q3","2025Q3"],"sample_count":8,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":3.22,"unit":"ug/L","quarters_used":["2021Q3","2023Q3","2024Q3","2025Q3"],"sample_count":8,"mcl":60,"exceeds_mcl":false}]}