Water Chemistry Data Dictionary

Beginning in 1992, water samples from wells, springs, and lakes were collected by DNR Waters staff and analyzed for natural water chemistry and isotopes. To date, DNR Waters staff have collected water samples from more than 1,500 sites, although not every sample has been analyzed for every parameter.

The data were collected by DNR staff as part of county and regional hydrogeologic studies for the county atlas and regional assessment series of reports published by DNR. Completed reports in the County Geologic Atlas or Regional Hydrogeologic Assessment series are available from the Minnesota Geological Survey and the Minnesota Department of Natural Resources. Please see the project status map for information on completed reports and studies in progress.

The data are currently managed in an MS Access database and are provided for download on the Chemistry Data Access page. The categories of data that are available, including site information and chemistry data, are shown in the list below.

The following table lists the water chemistry database field names and their definitions. The table is a reference for use with the chemistry data provided on the Chemistry Data Access page and the chemistry data provided with GIS (geographic information system) files for each completed atlas or assessment project.

For detailed information on the water chemistry data that is available, please see Chemistry Data Access.

For more information on the data dictionary, its contents, and parameter definitions, please contact Todd Petersen, Hydrologist, (651) 259-5698 [email protected]

Geographic and site information
RELATEIDFour 0's followed by 6 digit unique number for wells, or the Lake id from DNR Lakes Database + 2 digits for a site at a lake (01,02, etc.), or a 2-digit county number followed by 'A' followed by a 7-digit unique number for a spring
UNIQUE_NOUnique number for a well, or the lake name spelled out for a lake
UTME_83NAD 83 UTM Easting, extended zone 15
UTMN_83NAD 83 UTM Northing, extended zone 15
UTM_CODE Letter describing basis of UTM coordinates*
COUNTYCounty Name
QUAD_NAMEName of 1:24,000-scale 7.5 minute USGS topographic map
CTU_TYPELocal political subdivision type: city, township, or unorganized territory
CTU_NAMEName of city, township, or unorganized territory
TOWNSHIPTownship number, PLS
RANGERange number, PLS
RANGEDIRRange direction (E or W), PLS
SECTIONSection number, PLS
SUBSECTIONSubsections, A - northeast, B - northwest, C - southwest, D - southeast (listed order is largest to smallest)
ELEVATIONElevation of surface in feet
ELEVSOURCESource of elevation data: CWI, GPS, survey
DEPTH_COMPDepth of well completed in feet
AQUIFER See the files mgscodes.pdf or mgslut.dbf at MGS ftp site   for related information.
AQUIFER_QQuaternary aquifer name, usually mapped at county scale
PROJECTProject for which data was collected
SITETYPEType of site from which sample collected: well, spring, lake, stream, other

Chemistry Parameters
Measured in the field
DATE_SAMPDate of sample collection
COND_TC25Specific conductance of sample corrected to 25 degrees Celsius and reported as microsiemens per centimeter.
CONDSpecific conductance of sample reported as microsiemens per centimeter - may or may not be corrected for temperature.
TEMP_CTemperature in degrees Celsius of the water at the time of sampling
pHActivity of hydrogen ion
ORPOxidation-reduction potential in millivolts
DODissolved oxygen concentration in milligrams per liter
ALK_CACO3The total alkalinity of the solution reported as calcium carbonate in milligrams per liter
TOCThe total organic carbon in milligrams per liter
Anions
BR_DETBromide detection limit code**
BROMIDEBromide concentration in milligrams per liter
CL_DETChloride detection limit code**
CHLORIDEChloride concentration in milligrams per liter
F_DETFluoride detection limit code**
FLUORIDEFluoride concentration in milligrams per liter
NO3_DETNitrate detection limit code**
NITRATE_NNitrate concentration in milligrams per liter reported as Nitrogen
NO2_DETNitrite detection limit code**
NITRITE_NNitrite concentration in milligrams per liter reported as Nitrogen
PO4_DETPhosphate detection limit code**
PO4_PPhosphate concentration in milligrams per liter reported as Phosphorus
SO4_DETSulfate detection limit code**
SULFATESulfate concentration in milligrams per liter
SO4_SSulfate concentration in milligrams per liter reported as Sulfur
S2O3_DETThiosulfate detection limit code**
THIOSULFATEThiosulfate concentration in milligrams per liter
Cations
AL_DETAluminum detection limit code**
ALUMINUMAluminum concentration in milligrams per liter
BA_DETBarium detection limit code**
BARIUMBarium concentration in milligrams per liter
CA_DETCalcium detection limit code**
CALCIUMCalcium concentration in milligrams per liter
FE_DETIron detection limit code**
IRONIron concentration in milligrams per liter
MG_DETMagnesium detection limit code**
MAGNESIUMMagnesium concentration in milligrams per liter
MN_DETManganese detection limit code**
MANGANESEManganese concentration in milligrams per liter
P_DETPhosphorus detection limit code**
PHOSPHORUSPhosphorus concentration in milligrams per liter
K_DETPotassium detection limit code**
POTASSIUMPotassium concentration in milligrams per liter
SI_DETSilicon detection limit code**
SILICONSilicon concentration in milligrams per liter
NA_DETSodium detection limit code**
SODIUMSodium concentration in milligrams per liter
SR_DETStrontium detection limit code**
STRONTIUMStrontium concentration in milligrams per liter
TOTS_DETTotal sulfur detection limit code**
TOT_SULFURSulfur concentration in milligrams per liter as Sulfur
TOTP_DETTotal phosphorus detection limit code**
TOTP_PTotal phosphorus concentration in milligrams per liter
Trace Elements
SB_DETAntimony detection limit code**
ANTIMONYAntimony concentration in micrograms per liter
AS_DETArsenic detection limit code**
ARSENICArsenic concentration in micrograms per liter
BE_DETBeryllium detection limit code**
BERYLLIUMBeryllium concentration in micrograms per liter
B_DETBoron detection limit code**
BORONBoron concentration in micrograms per liter
CD_DETCadmium detection limit code**
CADMIUMCadmium concentration in micrograms per liter
CS_DETCesium detection limit code**
CESIUMCesium concentration in micrograms per liter
CR_DETChromium detection limit code**
CHROMIUMChromium concentration in micrograms per liter
CO_DETCobalt detection limit code**
COBALTCobalt concentration in micrograms per liter
CU_DETCopper detection limit code**
COPPERCopper concentration in micrograms per liter
I_DETIodine detection limit code**
IODINEIodine concentration in micrograms per liter
PB_DETLead detection limit code**
LEADLead concentration in micrograms per liter
LI_DETLithium detection limit code**
LITHIUMLithium concentration in micrograms per liter
MO_DETMolybdenum detection limit code**
MOLYBDENUMMolybdenum concentration in micrograms per liter
NI_DETNickel detection limit code**
NICKELNickel concentration in micrograms per liter
RB_DETRubidium detection limit code**
RUBIDIUMRubidium concentration in micrograms per liter
SE_DETSelenium detection limit code**
SELENIUMSelenium concentration in micrograms per liter
TL_DETThallium detection limit code**
THALLIUMThallium concentration in micrograms per liter
SN_DETTin detection limit code**
TINTin concentration in micrograms per liter
TI_DETTitanium detection limit code**
TITANIUMTitanium concentration in micrograms per liter
W_DETTungsten detection limit code**
TUNGSTENTungsten concentration in micrograms per liter
U_DETUranium detection limit code**
URANIUMUranium concentration in micrograms per liter
V_DETVanadium detection limit code**
VANADIUMVanadium concentration in micrograms per liter
ZN_DETZinc detection limit code**
ZINCZinc concentration in micrograms per liter
ZR_DETZirconium detection limit code**
ZIRCONIUMZirconium concentration in micrograms per liter
Tritium
H3_DETTritium detection limit code**
TRITIUMTritium in Tritium Units (TU)
H3_ERRORTritium error
Stable Isotopes
DEUTERIUMDeuterium (per mil)
OXYGEN_18Oxygen-18 (per mil)
SULFUR_34Sulfur-34 (per mil)
Carbon 14
C13Carbon-13 (per mil)
C13_SOILEstimate of Carbon-13 (per mil) in soil used in C14 model
C13METHANEEstimate of Carbon-13 (per mil) in produced methane used in C14 model
C14_CORRCorrected Carbon-14 activity; model estimate of Carbon-14 that originated as biospheric carbon
C14_ERRORCarbon-14 error
C14_METHODLaboratory method used to analyze sample
C14_MODELName of model used to estimate age
C14_PMCCarbon-14 reported as percent modern carbon
C14_YEARSModel estimated age in years rounded to 1 significant digit
Calculated Values
HARDNESSHardness in milligrams per liter
HARDNESS_GHardness in grains per gallon
TDSTotal dissolved solids in milligrams per liter

 

*UTM Code Values:
ADigitized at scale of 1:24,000 or greater MManual estimated from map or description)
BDigitized at scale of 1:100,000 to 1:24,000 SSurveyed
CDigitized at scale smaller than 1:100,000 (e.g., 1:200,000) TUTM coordinates calculated using SECTIC from TRS
DDigitized at unknown scale U " " TRS, Q (one Quarter-quad)
GGPS (type unspecified) V " " TRS, QQ (Quarter-Quarter quad, etc.)
GEGPS (engineering grade - horizontal accuracy approx. 1 cm) W " " TRS, QQQ
GHGPS (handheld - horizontal accuracy approx. 10 m) X " " TRS, QQQQ
GMGPS (mapping grade - horizontal accuracy approx. 0.5 m) Y " " TRS, QQQQQ
LUTM coordinates calculated using SECTIC from Lat/Long Z " " TRS, QQQQQQ

 

** Detection Limit Code Values:
  • blank - Reported concentration is the measured value
  • < - Reported concentration is the detection limit

 

Terms and Acronyms
CWICounty Well Index - database of wells in Minnesota maintained by MDH and MGS
DNRMinnesota Department of Natural Resources
GPSGlobal Positioning System
LAKEIDUnique identifier for lakes
MDHMinnesota Department of Health
MGSMinnesota Geological Survey
NAD 83North American Datum  
PLSPublic Land Survey
RELATEIDUnique identifier for wells, lakes, and springs used to relate database tables
SECTICProgram to translate Public Land Survey information to UTM coordinates, or UTM coordinates to PLS. Program and download information.  
USGSUnited States Geological Survey
UTMUniversal Transverse Mercator Map Projection