Name: Water Quality Data
Creator: harvest-sources
License: Other (Public Domain)

Themes include wildlife, fire, farmland, land use, renewable energy, geology, recreation.

natural-resources

Natural Resources

Themes include well water, water quality, wastewater, watershed, storm water, drinking water.

water

Water

Other (Public Domain)

water-quality-data

harvest-sources

Harvest Sources

Stations

Period of record for water quality data by station and parameter

### Parameters List (for search results):
Aminomethyl)phosphonic acid, *No Lab Analyses (Field Measures Only), 1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1,2-Trichlorotrifluoroethane, 1,1-Dichloroethane, 1,1-Dichloroethene, 1,1-Dichloropropene, 1,2,3-Trichlorobenzene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2,4-Trimethylbenzene, 1,2-Dibromo-3-chloropropane (DBCP), 1,2-Dibromoethane (EDB), 1,2-Dichlorobenzene, 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichlorobenzene, 1,3-Dichloropropane, 1,4-Dichlorobenzene, 1-Naphthol, 100-Day Biochemical Oxygen Demand, 2,2-Dichloropropane, 2,3,6-Trichlorobenzoic Acid, 2,3,7,8-Tetrachlorodibenzo-p-dioxin, 2,3-Dibromopropionic acid, 2,4,5-T, 2,4,5-TP (Silvex), 2,4-D, 2,4-DB, 2-Chloroallyl diethyldithiocarbamate (CDEC), 2-Chlorotoluene, 3-Hydroxycarbofuran, 4,4'-Dibromoctafluorobiphenyl, 4-Bromofluorobenzene, 4-Chlorotoluene, 4-Day Biochemical Oxygen Demand, 4-Isopropyltoluene, 5-Day Biochemical Oxygen Demand, 6-Day Biochemical Oxygen Demand, 7-Day Biochemical Oxygen Demand, Acenaphthene, Acenaphthylene, Acephate, Acifluorfen, Alachlor, Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Allethrin, Aminomethylphosphonic Acid (AMPA), Anthracene, Asbestos, Chrysotile, Atrazine, Atrazine-Simazine Mix, Azinphos methyl (Guthion), BHC, BHC-alpha, BHC-beta, BHC-delta, BHC-gamma (Lindane), Benfluralin, Bentazon, Benz(a)anthracene, Benzene, Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(ghi)perylene, Benzo(k)fluoranthene, Bicarbonate (HCO3-), Bifenthrin, Biochemical Oxygen Demand, Bis(2-ethylhexyl) adipate, Bromacil, Bromide, Bromobenzene, Bromochloroacetic Acid (BCAA), Bromochloroacetonitrile, Bromochloromethane, Bromodichloromethane, Bromoform, Bromomethane, Butachlor, Butyl benzyl phthalate, Captafol, Captan, Carbaryl, Carbofuran, Carbon tetrachloride, Carbonaceous Biochemical Oxygen Demand, Carbophenothion (Trithion), Chemical Oxygen Demand (COD), Chlordane, Chlorinated Hydrocarbons (General), Chlorobenzene, Chloroethane, Chloroform, Chloromethane, Chlorophyll a, Chloropicrin, Chloropropham, Chlorothalonil, Chlorpropham, Chlorpyrifos, Chorpropham, Chrysene, Clostridium perfringens, Color, Conductance, Cryptosporidium, Cyanazine, Cyanide, Cyfluthrin, Cypermethrin, DDD (all isomers), DDE (all isomers), DDT (all isomers), Dacthal (DCPA), Dalapon, Deltamethrin, Deltamethrin/Tralomethrin, Demeton (Demeton O + Demeton S), Di-n-butyl phthalate, Di-n-octyl phthalate, Diazinon, Dibenz(a,h)anthracene, Dibromoacetic Acid (DBAA), Dibromoacetonitrile, Dibromochloromethane, Dibromomethane, Dicamba, Dichlone, Dichloran, Dichloroacetic Acid (DCAA), Dichloroacetonitrile, Dichlorodifluoromethane, Dichloroprop, Dichloropropane - dichloropropene (D-D Mixture), Dichlorprop, Dicofol, Dicrotophos, Dieldrin, Diethyl phthalate, Dimethoate, Dimethyl phthalate, Dinoseb (DNPB), Dioxathion, Diquat, Dissolved Acid Hydrolyzable Phosphorus, Dissolved Aluminum, Dissolved Ammonia, Dissolved Antimony, Dissolved Arsenic, Dissolved Barium, Dissolved Beryllium, Dissolved Bicarbonate (HCO3-), Dissolved Bismuth, Dissolved Boron, Dissolved Bromide, Dissolved Cadmium, Dissolved Calcium, Dissolved Carbonate (CO3--), Dissolved Chloride, Dissolved Chromium, Dissolved Chromium, hexavalent (Cr6+), Dissolved Cobalt, Dissolved Copper, Dissolved Fluoride, Dissolved Gallium, Dissolved Germanium, Dissolved Hardness, Dissolved Hydroxide (OH-), Dissolved Iodide, Dissolved Iron, Dissolved Lead, Dissolved Lithium, Dissolved Magnesium, Dissolved Manganese, Dissolved Mercury, Dissolved Molybdenum, Dissolved Nickel, Dissolved Nitrate, Dissolved Nitrate + Nitrite, Dissolved Nitrite, Dissolved Organic Carbon, Dissolved Organic Nitrogen, Dissolved Ortho-phosphate, Dissolved Phosphorus, Dissolved Potassium, Dissolved Selenium, Dissolved Silica (SiO2), Dissolved Silver, Dissolved Sodium, Dissolved Strontium, Dissolved Sulfate, Dissolved Thallium, Dissolved Titanium, Dissolved Total Kjeldahl Nitrogen, Dissolved Uranium, Dissolved Vanadium, Dissolved Zinc, Disulfoton, Diuron, Endosulfan (mixed isomers), Endosulfan sulfate, Endosulfan-I, Endosulfan-II, Endothal, Endrin, Endrin aldehyde, Escherichia coli, Esfenvalerate, Ethion, Ethyl benzene, Ethylbenzene, Ethylene Dibromide, Ethylenethiourea, Fecal Coliform, Fenthion, Fenvalerate, Fibers > 10   ?m Asbestos, Chrysotile, Filtered Water Turbidity, Fluoranthene, Fluorene, Formetanate hydrochloride, Giardia lamblia, Glyphosate, Haloacetic Acid Formation Potential (HAAFP), Heptachlor, Heptachlor epoxide, Hexachlorobenzene, Hexachlorobutadiene, Hexachlorocyclopentadiene, Indeno(1,2,3-cd)pyrene, Inositol 1,4,5-Trisphosphate, Isopropylbenzene, MCPA, MCPP, Malathion, Metalaxyl, Methamidophos, Methidathion, Methiocarb, Methomyl, Methoxychlor, Methyl tert-butyl ether (MTBE), Methylene Blue Active Substances (MBAS), Methylene chloride, Metolachlor, Metribuzin, Mevinphos, Molinate, Monobromoacetic Acid (MBAA), Monochloroacetic Acid (MCAA), Naled, Naphthalene, Napropamide, Norflurazon, Oil and Grease, Organic Phosphorus Pesticides (OPP), Oxamyl, Oxyfluorfen, PCB's, PCB-1016, PCB-1221, PCB-1232, PCB-1242, PCB-1248, PCB-1254, PCB-1260, Paraoxon, Parathion, Ethyl, Parathion, Methyl, Pendimethalin, Pentachloronitrobenzene (PCNB), Pentachlorophenol (PCP), Permethrin, Perthane, Phenanthrene, Phenol, Phenols, Phenoxy Growth Regulators, Pheophytin a, Phorate, Phorate Sulfone, Phosalone, Phosmet, Picloram, Prallethrin, Profenofos, Prometryn, Pronamide, Propachlor, Propanil, Propargite, Propetamphos, Propham, Propoxur, Purgeable Halocarbons, Pyrene, Ronnel, Settleable Solids, Simazine, Specific Conductance, Styrene, Sulfallate, Sumithrin, Suspended + Volatile Suspended Solids, Suspended Solids, TEPP (Tetraethyl Pyrophosphate), Tannin and Lignin, Tefluthrin, Telodrin, Tetrachloroethene, Tetrachloroethylene, Tetrachlorofluoromethane, Tetrachlorophenols, Tetradifon (Tedion), Thiobencarb, Thiodicarb, Threshold Odor, Toluene, Total Alkalinity, Total Aluminum, Total Ammonia, Total Antimony, Total Arsenic, Total Asbestos, Chrysotile, Total Barium, Total Beryllium, Total Bismuth, Total Cadmium, Total Calcium, Total Chromium, Total Chromium, hexavalent (Cr6+), Total Cobalt, Total Coliform, Total Copper, Total Cyanide, Total Dissolved Solids, Total Gallium, Total Germanium, Total Hardness, Total Iron, Total Kjeldahl Nitrogen, Total Lead, Total Lithium, Total Magnesium, Total Manganese, Total Mercury, Total Methylmercury, Total Molybdenum, Total Nickel, Total Oil and Grease, Total Organic Carbon, Total Organic Nitrogen, Total Ortho-phosphate, Total Phenols, Total Phosphorus, Total Selenium, Total Silver, Total Strontium, Total Sulfides, Total Suspended Solids, Total Thallium, Total Titanium, Total Vanadium, Total Xylene, (total), Total Zinc, Toxaphene, Tralomethrin, Trichloroacetic Acid (TCAA), Trichloroacetonitrile, Trichloroethene, Trichlorofluoromethane, Triclopyr, Trifluralin, Trihalomethane Formation Potential (THMFP), Turbidity, UV Absorbance @254nm, Vinyl chloride, Volatile Suspended Solids, Xylene, (total), bis(2-Ethylhexyl) phthalate, cis-1,2-Dichloroethene, cis-1,3-Dichloropropene, l-Cyhalothrin, m + p Xylene, m-Xylene, n-Butylbenzene, n-Propylbenzene, o,p'-DDD, o,p'-DDE, o,p'-DDT, o-Xylene, p,p'-DDD, p,p'-DDE, p,p'-DDT, p-Xylene, pH, s,s,s-Tributyl Phosphorotrithioate (DEF), sec-Butylbenzene, tert-Butylbenzene, trans-1,2-Dichloroethene, trans-1,3-Dichloropropene

Period of Record by Station and Parameter

Lab Results

Field Results

This is a point feature class of environmental monitoring stations maintained in the California Department of Water Resources’ (hereafter the Department) Water Data Library Database (WDL) for discrete “grab” water quality sampling stations. The WDL database contains DWR-collected, current and historical, chemical and physical parameters found in drinking water, groundwater, and surface waters throughout the state. This dataset is comprised of a Stations point feature class and a related “Period of Record by Station and Parameter” table. The Stations point feature class contains basic information about each station including station name, station type, latitude, longitude, and the dates of the first and last sample collection events on record. The related Period of Record Table contains the list of parameters (i.e. chemical analyte or physical parameter) collected at each station along with the start date and end date (period of record) for each parameter and the number of data points collected. The Lab and Field results data associated with this discrete grab water quality stations dataset can be accessed from the California Natural Resources Agencies Open Data Platform at https://data.cnra.ca.gov/dataset/water-quality-data or from DWR’s Water Data Library web application at https://wdl.water.ca.gov/waterdatalibrary/WaterQualityDataLib.aspx

ArcGIS Map Service

This is a point feature class of environmental monitoring stations maintained in the California Department of Water Resources’ (hereafter the Department) Water Data Library Database (WDL) for discrete “grab” water quality sampling stations. The WDL database contains DWR-collected, current and historical, chemical and physical parameters found in drinking water, groundwater, and surface waters throughout the state. This dataset is comprised of a Stations point feature class and a related “Period of Record by Station and Parameter” table. The Stations point feature class contains basic information about each station including station name, station type, latitude, longitude, and the dates of the first and last sample collection events on record. The related Period of Record Table contains the list of parameters (i.e. chemical analyte or physical parameter) collected at each station along with the start date and end date (period of record) for each parameter and the number of data points collected. The Lab and Field results data associated with this discrete grab water quality stations dataset can be accessed from the California Natural Resources Agencies Open Data Platform at https://data.cnra.ca.gov/dataset/water-quality-data or from DWR’s Water Data Library web application at http://wdl.water.ca.gov/waterdatalibrary/index.cfm.

ArcGIS Feature Service

Some simple approaches to querying large csv datasets on CNRA Open Data.

Public Access Level	Public
Rights	No restrictions on public use
Program Contact Name	Water Data Library
Program Contact Email	wdlweb@water.ca.gov
Homepage URL	http://www.water.ca.gov/waterdatalibrary/
Frequency	Irregular
Last Updated	October 7, 2026 at 5:20 PM (UTC+00:00)
Created	July 18, 2025 at 12:23 AM (UTC+00:00)
License	Other (Public Domain)
Tags	#Groundwater#Surface Water#WDL#Water Data Library#Water Quality#california department of water resources

Water Quality Data

Data and Resources

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