National Drinking Water Database
City of Napa - Napa, CA
Serves 70,000 people - Test data available: 2004-2009
This drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group (EWG) by the California Department of Public Health. It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results. Water utilities nationwide detected more than 300 pollutants between 2004 and 2009. More than half of these chemicals are unregulated, legal in any amount. Despite this widespread contamination, the federal government invests few resources to protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes test results for this utility and lists potential health concerns.
Contaminants Exceeding Health Guidelines
-Tested 
-Detected 
-Over Health Guidelines 
-Over Legal Limit*
Other Detected Contaminants
Contaminants Not Detected - 152 chemicals
1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloroethane, 1,1-Dichloroethylene, 1,1-Dichloropropene, 1,2,3-Trichlorobenzene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2,4-Trimethylbenzene, 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichloropropane, 1,3-Dichloropropene, 1,4-Dioxane, 2,2-Dichloropropane, 2,3,7,8-TCDD (Dioxin), 2,4,5-t, 2,4,5-TP (Silvex), 2,4-d, 2-Chloroethylvinyl ether, 3-Hydroxycarbofuran, Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Aminocarb, Antimony (total), Arsenic (total), Asbestos, Atrazine, Barban, Barium (total), Baygon (Propoxur), Bentazon (Basagran), Benzene, Benzo[a]pyrene, Beryllium (total), bis(2-chloroethyl) ether, Bromacil, Bromate, Bromobenzene, Bromochloromethane, Bromomethane, Butachlor, Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chlorite, Chloroethane, Chlorothalonil (Bravo), Chlorotoluene, Chlorpropham, Chromium (hexavalent), Chromium (total), cis-1,2-Dichloroethylene, Combined Uranium (mg/L), Copper, Cyanide, Dacthal, Dalapon, Di(2-Ethylhexyl) adipate, Diazinon (Spectracide), Dibromomethane, Dicamba, Dichlorodifluoromethane, Dichloromethane (methylene chloride), Dieldrin, Dimethoate, Dinoseb, Diquat, Diuron, Endothall, Endrin, Ethyl-t-butyl ether (ETBE), Ethylbenzene, Fenuron, Fluometuron, Glyphosate, Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Hydrogen sulfide, Isopropyl ether, Isopropylbenzene, Lindane, Linuron, m- & p- Xylene, m-Dichlorobenzene, m-Xylene, Methiocarb, Methomyl, Methoxychlor, Methyl ethyl ketone, Methyl isobutyl ketone, Metolachlor, Metribuzin, Mexacarbate, Molinate (Ordram), Molybdenum, Monobromoacetic acid, Monochlorobenzene (Chlorobenzene), Monuron, Mtbe, n-Butylbenzene, n-Propylbenzene, Naphthalene, Neburon, Nitrate, Nitrite, o-Chlorotoluene, o-Dichlorobenzene, o-Xylene, Oxamyl (Vydate), p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, p-Xylene, Pentachlorophenol, Perchlorate, Picloram, Prometryn, Propachlor, Propham, Radium-226, sec-Butylbenzene, Selenium (total), Siduron, Silver (total), Simazine, Styrene, Tert-Amyl-Methyl Ether, tert-Butylbenzene, Tetrachloroethylene, Thallium (total), Thiobencarb (Bolero), Toluene, Total polychlorinated biphenyls (PCBs), Toxaphene, trans-1,2-Dichloroethylene, trans-1,3-Dichloropropene, Trichloroethylene, Trichlorofluoromethane, Trichlorotrifluoroethane, Vinyl chloride, Xylenes (total)
Pollution Summary
EPA Violation Summary
No violations were reported for this system since 2004.
Information on violations is drawn directly from EPA's national violations database in the Agency's Safe Drinking Water Information System. Analyses by others have raised questions about the quality of the information in EPA's database. For the purposes of this investigation, EWG is not showing below or including in our analyses, those violations for individual water suppliers that occurred on days for which the total number of violations assigned by EPA to that water supplier was greater than 20. This criteria was based on common characteristics of incorrect violations data as identified by water utilities, from a review of EPA's violations data by several hundred utilities prior to the release of EWG's investigation.