U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES 37 Data from Selected U.S. Geological Survey National Stream Water-Quality Monitoring Networks (WQN) [This is the \DOCFILES\DATA_DOS.TXT file] WQN DATA FILES The data are provided in two different forms separately on two CD-ROM discs: (1) The "ASCII disc" contains all WQN data in ASCII form, and is readable on any computer capable of reading ISO 9660 standard CD-ROM discs. These data can be searched or accessed through user-supplied software including Web browser (e.g., Mosaic, Netscape Navigator, or Microsoft Internet Explorer), word processor, spreadsheet, statistical analysis programming software, or geographic information systems. See the DATA_ALL.TXT file for a description of the ASCII data structure. (2) The "DOS disc" can be used to access all WQN data (except for daily streamflow values and selected graphical files associated with the technical memoranda) on a DOS-based computer or under a DOS emulator on another computer (software on this disc is also executable from a Windows operating system). The software supplied on the DOS disc (GSMENU and GSSEARCH) allows the user to browse text files and retrieve and output data according to user-specified criteria. See DATA_DOS.TXT file for a description of the DOS-accessible data structure. [The contents of the DOS disc are described below] THE WQN DOS DATA FILES The WQN data base contains water-quality and streamflow data and supporting information identifying and describing the water-quality and streamflow stations, water-quality constituents, and the methods, remarks, laboratories, sample collection agencies, and the measurement accuracy associated with the WQN data. Water-quality and streamflow data approximately span the periods 1973-95 for the National Stream Quality Accounting Network (NASQAN) and 1962-95 for the Hydrologic Benchmark Network (HBN). Estimates of laboratory measurement accuracy of the stream water-quality data based on water reference samples are included in a quality-control data base covering the water years 1985-95 (Oct. 1, 1984 to Sept. 30, 1995). The DOS-compatible GSSEARCH software allows the user to retrieve and output the water-quality and quality-assurance data and the supporting ancillary information (daily streamflow data can only be accessed from the ASCII disc). Any of the fields in the data bases may be used to specify retrieval criteria. User-selected data may be output in a variety of formats including dBASE, flat ASCII, delimited ASCII, or fixed-field. Text files containing supporting documentation and quality- assurance information on network protocols and field and laboratory methods can be browsed using GSMENU software. These browsable text files include USGS technical memoranda documenting national water-quality network operations and important changes in field and laboratory methods used in the operation of the national networks. GSSEARCH-ACCESSIBLE WQN DATA FILES The data contained in 15 files can be accessed using GSSEARCH software. These files and their contents as well as the field names and their definitions are described below. WQ_PARM.DAT Contains a list of 121 physical, chemical, and ----------- biological constituents for which stream water-quality data are available on the CD-ROM. Their units of measure, chemical expression, and unique five digit parameter code are provided. WQ_GRP A 3-character name assigned to logical groupings of physical, field, chemical, and biological constituents (e.g., NUT = nutrients). These names are used to identify ASCII water-quality datafiles in \WQN sub-directories. SNAME An 8-character constituent short name. PARM A 5-digit unique parameter code for identifying the water-quality constituent. METH_FLAG A 1-character indicator of the availability of information on laboratory analytical methods. The character "*" denotes constituents with information on one or more laboratory analytical methods in the file METHODS.DAT. A blank denotes field parameters or constituents without information on the laboratory method codes. With the exception of alkalinity, bicarbonate, and carbonate, method codes that appear in the water-quality file (WQ_DATA.DAT) for these blank-denoted constituents are not officially maintained. LNAME An 84-character long name of the constituent identifying the units of measure and chemical expression of the constituent. WQ_DATA.DAT Contains all the stream water-quality data and the ----------- attributes for the 679 monitoring stations. The data approximately span the period 1973-95 for NASQAN stations and 1962-95 for HBN stations. STA_NUM Station number - the 8 digit station number uniquely identifying the water-quality station. STA_NAME Station name - the 48 character name of the water-quality station. HUC The 8 digit Hydrologic Unit Code identifying the drainage basin. The first two digits of the HUC specify the Water Resources Council region. The econd two digits specify the sub-basin. The next two digits give the accounting unit. The final two digits give the cataloging unit. [See HUCS.TXT in /WQN/WQ sub-directory for explanation] DRAIN_AREA The area of the drainage basin in square miles. STATE State - the two character abbreviation of the state in which the water-quality station is located. See the STATES.DAT file in /WQN/WQ for a list of these abbreviations. COUNTY County - the code number of the county in which the water-quality station is located. See Federal Information Processing Standards Publication (FIPS PUBS) 6-3 for a list of these codes. LATITUDE Latitude of the water-quality station in the form DDMMSS where D is degrees, M is minutes, and S is seconds. LONGITUDE Longitude of the water-quality station in the form DDDMMSS. NATNET Network identifier (NASQAN = 'N'; Benchmark = 'B'). STA_BEG_DT Station beginning date (YYYYMMDD). STA_END_DT Station ending date (YYYYMMDD). POP_1990 Basin 1990 population density (no. persons/square mile). P_URBAN Basin 1987 urban land area in percent. P_CROP Basin 1987 crop land area in percent. P_PASTURE Basin 1987 pasture land area in percent. P_FOREST Basin 1987 forest land area in percent. P_RANGE Basin 1987 range land area in percent. P_FARM Basin 1987 farm land area in percent. P_OTHER Basin 1987 other land area in percent (includes water, rural transportation, barren land, and federal land). BAS_TYPE Drainage basin used to compile land-cover and population statistics (1=NASQAN; 2=Accounting unit containing NASQAN station; 3=No data -- a Benchmark station or the station is located outside of the conterminous United States -- a missing value indicator of a negative sign and sufficient values of 9 to fill the land-cover or population field width is used). HUC_NAME Hydrologic unit name. SAMP_MONTH Beginning month sample was taken. SAMP_DATE Beginning date sample was taken (YYYYMMDD). SAMP_TIME Beginning time sample was taken (HHMM - 24 hr. clock). SAMP_END_D Ending date sample was taken (YYYYMMDD). AGENCY_CD Sample collection agency code (see AGENCIES.DAT). LAB_CODE Laboratory analysis agency code (see LABS.DAT). INSTFLOW_V Value for parameter 00061 Instantaneous Streamflow (cubic feet per second). INSTFLOW_R Remark code for parameter 00061 Instantaneous Streamflow. INSTFLOW_M Method code for parameter 00061 Instantaneous Streamflow. The following three fields are repeated for each of the 121 parameters listed in the WQ_PARM.DAT file, and give the values and the remark and method codes: wqparm_V Value for indicated parameter. wqparm_R Remark code for indicated parameter (see REMARKS.DAT). wqparm_M Laboratory or field analysis method code for indicated parameter (see METHODS.DAT). where wqparm is equal to the constituent short name (SNAME) listed in WQ_PARM.DAT. A missing value indicator of a negative sign and sufficient values of 9 to fill the specified field width is used. A blank is used to indicate missing value for the method code field. A blank in a remark field indicates that no special conditions are associated with the value. If all water- quality measurements are missing for a single sample, the record was excluded from the file. Negative streamflow values indicate reverse flow resulting from wind, backwater, or tidal effects. WQ_STAS.DAT List the identifying number, name, and other attributes ----------- of the 679 national network stations. STA_NUM Station number - the 8 digit station number uniquely dentifying the water-quality station. STA_NAME Station name - the 48 character name of the water-quality station. HUC The 8 digit Hydrologic Unit Code identifying the drainage basin. The first two digits of the HUC specify the Water Resources Council region. The second two digits specify the sub-basin. The next two digits give the accounting unit. The final two digits give the cataloging unit. [See HUCS.TXT in /WQN/WQ sub-directory for explanation] DRAIN_AREA The area of the drainage basin in square miles. STATE State - the two character abbreviation of the state in which the water-quality station is located. See the STATES.DAT file for a list of these abbreviations. COUNTY County - the code number of the county in which the water-quality station is located. See Federal Information Processing Standards Publication (FIPS PUBS) 6-3 for a list of these codes. LATITUDE Latitude of the water-quality station in the form DDMMSS where D is degrees, M is minutes, and S is seconds. LONGITUDE Longitude of the water-quality station in the form DDDMMSS. NATNET Network identifier (NASQAN = N; Benchmark = B). STA_BEG_DT Station beginning date (YYYYMMDD). STA_END_DT Station ending date (YYYYMMDD). POP_1990 Basin 1990 population density (no. persons/square mile). P_URBAN Basin 1987 urban land area in percent. P_CROP Basin 1987 crop land area in percent. P_PASTURE Basin 1987 pasture land area in percent. P_FOREST Basin 1987 forest land area in percent. P_RANGE Basin 1987 range land area in percent. P_FARM Basin 1987 farm land area in percent. P_OTHER Basin 1987 other land area in percent (includes water, rural transportation, barren land, and federal land). BAS_TYPE Drainage basin used to compile land-cover and population statistics (1=NASQAN; 2=Accounting unit containing NASQAN station; 3=No data -- a Benchmark station or the station is located outside of the conterminous United States -- a missing value indicator of a negative sign and sufficient values of 9 to fill the land-cover or population field width is used). HUC_NAME Hydrologic unit name [See HUCS.TXT in /WQN/WQ sub-directory for explanation] WQ_RELOC.DAT A list of 48 NASQAN water-quality stations that were ------------ relocated during their period of operation. This file gives the 8-digit station number, station name, and dates of network operation. This information may be used to identify stations where records may be suitable for merging. RELOC_MRK Indicator of type of relocation ('*' indicates that the station was moved to another river; a blank indicates that the site was moved to another location in the same river). STA_NUM Station number - the 8 digit station number uniquely identifying the water-quality station. STA_NAME Station name - the 48 character name of the water-quality station. STA_BEG_DT Station beginning date (YYYYMMDD). STA_END_DT Station ending date (YYYYMMDD). RSTA_NUM New relocated station number - the 8 digit station number uniquely identifying the water-quality station. RSTA_NAME New reloctated station name - the 48 character name of the water-quality station. RSTA_BEG_D New relocated station beginning date (YYYYMMDD). RSTA_END_D New relocated station ending date (YYYYMMDD). WQ_MVNET.DAT A list of 2 stations that belonged to both national ------------ networks (NASQAN and Benchmark) during the period of operations. STA_NUM Station number - the 8 digit station number uniquely identifying the water-quality station. STA_NAME Station name - the 48 character name of the water-quality station. STA_BEG_DT NASQAN station beginning date (YYYYMMDD). STA_END_DT NASQAN station ending date (YYYYMMDD). BSTA_BEG_D Benchmark station beginning date (YYYYMMDD). WQ_FLOW.DAT Contains information on the availability of streamflow ----------- records for each of the 679 water-quality stations. Alternate streamflow stations, located in the vicinity of 79 NASQAN monitoring stations, are identified. In some cases, the alternate streamflow gaging station is a relocated NASQAN station (19 stations). In one case, the streamflow at NASQAN site 01096550 can be determined from the streamflow of two upstream gaging sites, 01100000 and 01099500 [contact the USGS New England District office for details; see the file CONTACTS.TXT for instructions]. STA_NUM Station number - the 8 digit station number uniquely dentifying the water-quality station. STA_NAME Station name - the 48 character name of the water-quality station. CODE Streamflow station/record code (0=streamflow is recorded at the water-quality station; 1=streamflow is recorded at a nearby alternate streamflow gaging site or a nearby relocated NASQAN station; 2=no streamflow record is available for the water-quality station.) FSTA_NUM Alternate streamflow gaging station number -- the 8-digit number uniquely identifying the streamflow station. FSTA_NAME Alternate streamflow gaging station name -- the 48 character name of the streamflow station. BEGIN_YR Beginning year of daily streamflow record. END_YR Ending year of daily streamflow record. NUM_FLOW Number of daily streamflow values. FLOWSTAS.DAT Gives the master index of 61 alternate stream gaging ------------ stations (with daily mean values) located in the vicinity of NASQAN monitoring sites. Records of daily mean streamflow from these stations are suitable for estimating daily flow at the national network monitoring sites. FSTA_NUM Station number - the 8 digit station number uniquely identifying the streamflow gaging station. FSTA_NAME Station name - the 48 character name of the streamflow gaging station. HUC The 8 digit Hydrologic Unit Code identifying the drainage basin. The first two digits of the HUC specify the Water Resources Council region. The second two digits specify the sub-basin. The next two digits give the accounting unit. The final two digits give the cataloging unit. DRAIN_AREA The area of the drainage basin in square miles. STATE State - the two character abbreviation of the state in which the gaging station is located. See the STATES.DAT file for a list of these abbreviations. COUNTY County - the code number of the county in which the gaging station is located. See Federal Information Processing Standards Publication (FIPS PUBS) 6-3 for a list of these codes. LATITUDE Latitude of the gaging station in the form DDMMSS where D is degrees, M is minutes, and S is seconds. LONGITUDE Longitude of the gaging station in the form DDDMMSS. POP_1990 Accounting unit 1990 population density (no. persons/square mile). P_URBAN Accounting unit 1987 urban land area in percent. P_CROP Accounting unit 1987 crop land area in percent. P_PASTURE Accounting unit 1987 pasture land area in percent. P_FOREST Accounting unit 1987 forest land area in percent. P_RANGE Accounting unit 1987 range land area in percent. P_FARM Accounting unit 1987 farm land area in percent. P_OTHER Accounting unit 1987 other land area in percent (includes water, rural transportation, barren land, and federal land). HUC_NAME Hydrologic unit name. AGENCIES.DAT List the governmental and private organizations ------------ responsible for sample collection of the network stream water-quality data and their corresponding sample collection codes (AGENCY_CD) given in the WQ_DATA.DAT file. These codes were frequently reported in the data base beginning in the early 1980s. Non-USGS agencies may have periodically collected data at WQN sites as part of local investigations. AGENCY_CD Sample collection agency code. AGENCY_NAM Agency or organizational name. LABS.DAT List the governmental and private organizations -------- responsible for laboratory analysis of the network stream water-quality data and their corresponding laboratory analytical codes (LAB_CODE) given in the WQ_DATA.DAT file. These codes were frequently reported in the data base beginning in the early 1980s. Non-USGS laboratories may have periodically analyzed samples collected as part of local investigations conducted at WQN sites. LAB_CODE Laboratory analysis agency code. LAB_NAME Agency or organizational name. METHODS.DAT Contains definitions of the laboratory analytical methods ----------- codes corresponding to the values of water quality in the WQ_DATA.DAT file. These codes are reported beginning in 1985. Descriptive information is given for 209 laboratory methods used to analyze 76 of the 121 water-quality constituents (other analytical methods not listed in this file may have been used to analyze some of these constituents; information on these methods was unavailable at the time of CD-ROM production). The remaining 46 constituents include 17 laboratory-analyzed parameters for which codes were unavailable at the time of CD-ROM production, 27 field parameters, and 2 computed parameters. The 17 constituents include 1 trace element, 4 radiochemicals, and 12 biological constituents (these predated the use of method codes). Although method codes are reported in the water-quality data base for the 27 field and 2 computed parameters, these codes are not officially supported by the USGS. PARM A 5-digit unique parameter code for identifying the water-quality constituent (see character identification in the WQ_PARM.DAT file). METH_CODE Water-quality constituent laboratory analysis method code (Code corresponds to the wqparm_M codes associated with the water-quality value for each parameter code in the WQ_DATA.DAT file). FMETH_CODE Fishman laboratory method code (see Fishman and others, 1994). CNAME Water-quality constituent descriptor (64 characters). METH_SNAME Laboratory analytical method short name (5 character). MRL Method reporting limit of the analytical method. REF USGS publication including Techniques of Water Resources Investigations (TWRI) or Open-File Report (OFR). METH_LNAME Laboratory analytical method long name descriptor (47 chars). REMARKS.DAT Contains definitions for remark codes corresponding ----------- to the values of water quality in the WQ_DATA.DAT file. REMARK Remark code (Code corresponds to the wqparm_R codes associated with the water-quality value for each parameter code in the WQ_DATA.DAT file). RMK_EXPLAN Explanation of remark code (69 characters). BSP_PARM.DAT Contains the list of 34 dissolved chemical constituents ------------ for which Blind Sample Program (BSP) reference sample data are available for water years 1985-95 (Oct. 1, 1984 to Sept. 30, 1995). The BSP data can be used to estimate the laboratory measurement bias and variability associated with national network stream water-quality observations. The methods, laboratories, and collection agencies should be identical for the BSP data and WQN stream water- quality data. See the accompanying Open-File Report for a complete discussion of the characteristics of BSP data and statistical methods for using these data to assist in the interpretation of WQN data. BSP_GRP A 3-character name assigned to logical groupings of the chemical constituents (e.g., NUT = nutrients). SNAME An 8-character constituent short name. PARM A 5-digit unique parameter code for identifying the water-quality constituent. LNAME An 56-character long name of the constituent identifying the units of measure and chemical expression of the constituent. BSP_METH.DAT Contains a listing of the laboratory analytical methods ------------ and years for the 34 chemical constituents for which BSP quality-assurance data were selected (Table 9 in the accompanying Open-File Report). These analytical methods were used for the analysis of national network water-quality data for the years and constituents indicated. BSP_GRP A 3-character name assigned to logical groupings of the chemical constituents (e.g., NUT = nutrients). LNAME A 36-character long name of the constituent. PARM A 5-digit unique parameter code for identifying the water-quality constituent. METH_CODE Water-quality constituent laboratory analysis method code. BEGIN_WY Beginning water year (Oct. to Sept.) for use of laboratory analytical method. END_WY Ending water year (Oct. to Sept.) for use of laboratory analytical method. MRL Method reporting limit of the analytical method. BIAS.DAT Contains the Blind Sample Program (BSP) data on laboratory -------- measurement error for 34 chemical constituents for water years 1985-95 (Oct. 1, 1984 to Sept. 30, 1995). See BSP_PARM.DAT for a listing of the constituents. These data provide estimates of the laboratory measurement error associated with selected WQN stream water-quality constituents. See the accompanying Open-File Report for a complete discussion of the characteristics of BSP data and statistical methods for using these data to estimate laboratory measurement bias and to assist in the interpretation of WQN data. LOG_DATE Laboratory sample login date (YYYYMMDD) of the BSP reference sample. BSP_MIX Unique 12-character mixture number identifying the BSP sample. SEQ A sequence number indicating the number of BSP samples with an identical mix analyzed on the same day. The following five fields are repeated for each of the 34 parameters listed in the BSP_PARM.DAT file, and give the following BSP error statistics: wqparm_V Laboratory measurement value for indicated parameter. wqparm_MPV BSP MPV (most probable value) for indicated parameter. wqparm_NSD BSP NSD (number of standard deviations) for indicated parameter. wqparm_ERR Laboratory measurement error in percent for indicated parameter (Computed as the difference between the laboratory measurement and the MPV of the reference sample, expressed as a percent of the MPV. For remarked values, the error is computed by expressing the reporting limit as a percentage of the MPV. A negative sign is assigned to error values where a negative difference is obtained between the laboratory measurement and the MPV). wqparm_R Error remark code ("<") for indicated parameter (Identifies error values--in absolute units--that are less than or equal to the method reporting limit). where wqparm is equal to the constituent short name (SNAME) listed in BSP_PARM.DAT. VAR.DAT Contains the Blind Sample Program (BSP) estimates of ------- laboratory measurement variability for 34 chemical constituents for the years 1985-95 (Oct. 1, 1984 to Sept. 30, 1995). See BSP_PARM.DAT for a listing of the constituents. These data provide estimates of the laboratory measurement variability associated with selected WQN stream water- quality constituents. See the accompanying Open-File Report for a complete discussion of the characteristics of the BSP data and statistical methods for using these data to assist in the interpretation of WQN data. BLOG_DATE Earliest laboratory login date (YYYYMMDD) of the BSP reference sample. ELOG_DATE Latest laboratory login date (YYYYMMDD) of the BSP reference sample. BSP_MIX Unique 12-character mixture number identifying the BSP sample. The following five fields are repeated for each of the 34 parameters listed in the BSP_PARM.DAT file, and give the following BSP error statistics: wqparm_MPV BSP MPV (most probable value) for indicated parameter. wqparm_MN NWQL mean for indicated parameter. wqparm_STD NWQL standard deviation for indicated parameter. wqparm_NUM The number of observations used to estimate the mean and standard deviation for indicated parameter. wqparm_RSD NWQL RSD (relative standard deviation) for indicated parameter. where wqparm is equal to the constituent short name (SNAME) listed in BSP_PARM.DAT. GSMENU-BROWSABLE WQN DATA FILES The data contained in 69 text files can be browsed using GSMENU software. These files and their contents are described below. WQ_PARM.TXT A list of the 63 water properties for which data are ----------- available on the CD-ROM and their approximate sampling frequencies. (This file is Table 2 in the accompanying Open-File Report) WQ_DEFS.TXT Explains the total constituent analyses performed on ----------- WQN samples. The total form reflects different characteristics of the analytical methods and the water-suspended sediment mixture of the samples. (This file is Table 7 in the accompanying Open-File Report) SEAS_DEF.TXT Contains NASQAN and HBN time periods of sample collection ------------ for bimonthly and quarterly sampling frequencies. (This file is Table 3 in the accompanying Open-File Report) ALK_PARM.TXT Contains the applicable parameter/method codes and ------------ dates used to compile national network alkalinity, bicarbonate, and carbonate data on the CD-ROM. (This file is Table 6 in the accompanying Open-File Report) REPORT.TXT The accompanying USGS Open-File Report discussing the ---------- history and characteristics of the WQN data including the stream water-quality data and the Blind Sample Program (BSP) reference sample data. This report also describes statistical methods for using the BSP reference sample data to evaluate the accuracy of network stream water- quality data. [The accompanying report is entitled "Data from Selected U.S. Geological Survey National Stream Water Quality Monitoring Networks (WQN) on CD-ROM" by R.B. Alexander, A.S. Ludtke, K.K. Fitzgerald, and T.L. Schertz, U.S. Geological Survey Open-File Report 96-337.] BIBLIO.TXT A bibliography of publications on national network field and ---------- laboratory methods, network historical background, interpretations of network data at the national, regional, and local levels, and statistical and computer software methods that have been developed for use with data having characteristics similar to those of the national network data. QA_FLD.TXT Gives a summary of important changes in WQN field ---------- methods, constituent coverage, and field sample contamination that may affect the use and interpretation of WQN stream water-quality data. (This file is Table 4 in the accompanying Open-File Report) QA_LAB.TXT Gives a summary of important changes in WQN laboratory ---------- methods, reporting conventions, and laboratory sample contamination that may affect the use and interpretation of WQN stream water-quality data. (This file is Table 8 in the accompanying Open-File Report) QA_MEMOS.TXT Gives a brief summary of 60 USGS water-quality memoranda ------------ cited in QA_FLD.TXT and QA_LAB.TXT and describing changes in methods, constituent coverage, and sample contamination that may affect the use and interpretation of WQN stream water-quality data. The memoranda are listed chronologically within six topical areas. (This file is Table 5 in the accompanying Open-File Report) XXyy_nn.TXT The text of the separate USGS water-quality memoranda ----------- (listed in QA_MEMOS.TXT) are identified according to this unique memorandum number where XX is the originating office (QW = Office of Water Quality, NL = National Water Quality Laboratory), yy refers to the year the memorandum was released and nn is a sequential number of the year's memoranda or a special character string. The sub-directory \WQN\QASURE\GRAPHICS contains figures and tables (landscape mode) stored in PostScript (PS) and GIF format for seven of the memoranda. The naming convention for these files is QWyy_nna.TXT where 'a' is a sequential character corresponding to the order of presentation of figures and tables in the memoranda. A user-supplied graphical viewer is required to access these files. Versions of these files provided on the ASCII disc are viewable via user-supplied Web browser. Refer to the 1ST_READ.ME file in this sub-directory for a listing of the figure and table names.