VARIABLE DESCRIPTION SAMPLE_TYPE UNITS RANGE_LOW RANGE_HIGH LEGAL_VALUES AG_ECO3 "NARS 3-level reporting region (2015), based on aggregating AGGR_ECO9_2015 reporting regions" DESIGN EHIGH|PLNLOW|WMTNS AG_ECO3_NM NARS 3-level reporting region Name DESIGN Text names AG_ECO9 "NARS 9-level reporting region (2015), based on aggregated Omernik Level III ecoregions" DESIGN CPL|NAP|NPL|SAP|SPL|TPL|UMW|WMT|XER AG_ECO9_NM NARS 9-level reporting region Name DESIGN Text names BOAT_WADE NRSA 2008-9 site was boatable or wadeable when sampled DESIGN Boatable|Wadeable BORD_RIV Reach occurs on state or country boundaries DESIGN Text of two postal codes: MM:NN where MM is one state and NN is other state the river is on the border. Blank if not a border river CH0813_WGT Site weight for 2008-9 and 2013-14 change analysis DESIGN Numeric: >0 or 0 if site is not to be used for population estimation CHNG_SF "Identifies if site included/excluded from 2008-9, 2013-14, 2018-19 sample frame. Will expand in future to include 2023-24 etc." DESIGN Form: Include18_Include13_Include08 CNTYNAME County name (source ESRI counties based on census 2010) DESIGN Text Names COMID NHD common identifier for NRSA sampling frame and subsequent designs. DESIGN Numeric DATE_COL Date of data collection in field DESC_CODE Land ownership description code derived from USGS PADUS (http://gapanalysis.usgs.gov/padus/data/) - pulled May 2016 version of database DESIGN Numeric of 37 land ownership description codes from PADUS; may legitimately be NA if not covered by PADUS owership ELEVATION "Elevation at Stream site (LAT_DD83, LON_DD83) from USGS elevation point query service (30 m elevation) http://ned.usgs.gov/epqs/" DESIGN Numeric; may legitimately be negative EPA_REG EPA Region DESIGN Region_1 | Region_2 | Region_3 | Region_4 | Region_5 | Region_6 | Region_7 | Region_8 | Region_9 | Region_10 EVALSTAT "Status assigned based on site evaluation guidelines and responses to verification form, if sampled." EVAL TargetSampleable|TargetNotSampled|TargetOther|AccessDenied|Inaccessible-Barrier/Safety|Inaccessible-Effort|Nontarget-CoastalSaline|Nontarget-Ephemeral|Nontarget-MapError|Nontarget-NoRecAquatUse|Nontarget-NotLake|Nontarget-Other|Nontarget-TooSmall|Nontarget-TooShallow|NonTarget-Vegetated|NotNeeded EVALUATED Was site evaluated for sampling? EVAL YES|NO FEOW_ID Freshwater Ecoregions of the World (2015) code DESIGN Numeric FRAME14 "Identifies whether site is part of NRSA_ST, NRSA_only, or state only" DESIGN FRAME18_ID 2018-19 Sampling Frame ID code DESIGN FS_EW Eastern or western US Forest Service land DESIGN East | West | blank if not US Forest Service land GNIS_ID Goegraphic Names Information System ID (from NHD) DESIGN Numeric GNIS_NAME USGS Geographic Names Information System name DESIGN Text name HUC2 USGS Level 2 Hydrologic Unit Code where stream reach is located (based on NHDPlusV2 use of HUCs) DESIGN Alphanumeric: H01 to H20 with H03N :H 03S : H03W | H10L : H10U where region coded preceded by letter H HUC2_REG USGS Level 2 Hydrologic Unit Region Name where stream reach is located (based on NHDPlusV2 use of HUCs) DESIGN Text name of Region HUC8 USGS Level 8 Hydrologic Unit Code where stream reach is located (based on NHDPlusV2 use of HUCs) DESIGN Alphanumeric code; 8-digit preceded by letter H HUC8_NM USGS Level 8 Hydrologic Cataloging Unit Name where stream reach is located DESIGN Text LAT_DD83 Latitude (based on NAD83 datum) for stream site from NHD-based sample frame. DESIGN Numeric LON_DD83 Longitude (based on NAD83 datum) for stream site from NHD-based sample frame. DESIGN Numeric MAJ_BAS_NM Major USGS Hydrologic Basins derived from NHDPlus Names DESIGN Text of 16 basin names MAJ_BASIN Major USGS Hydrologic Basins derived from NHDPlus Codes DESIGN 16 Major Basin Codes from 01 to 18 with 05_06 and 12_13 combined preceeded by letter H MISS_BASIN "The hydrologic basin name for streams in the Mississippi Basin, or NA for streams not in the Mississippi Basin" DESIGN Text of 7 basin names or NA MISS_BASIN_NM Mississippi basin name DESIGN Ohio Region|Tennessee Region|Upper Mississippi Region|Lower Mississippi Region|Lower Missouri Region|Upper Missouri Region|Arkansas-White-Red Region NA_L1CODE CEC North American Level I ecoregion code DESIGN Numeric 5 to 15 excluding 14 and 0 designating HI NA_L1NAME CEC North American Level I ecoregion name DESIGN Text NA_L2CODE CEC North American Level II ecoregion code DESIGN Alphanumeric: n.n where leading position is Level I code and following position is Level 2 designation NA_L2NAME CEC North American Level II ecoregion name DESIGN Text NA_L3CODE CEC North American Level III ecoregion code DESIGN Alphanumeric: n.n.n where leading two positons are Level II code and following position is level 3 designation NA_L3NAME CEC North American Level III ecoregion name DESIGN Text NARS_NAME Name of lake from field evaluation or GNIS NAME if the same DESIGN Text NARS_OWN Land ownership category used by NARS DESIGN Text of 13 land ownership category names NFWAWGTCAT Categories used to create weights for the analysis of NRSA 2008-9 survey DESIGN NRS13_EVAL NRSA 2013/14 site evaluation result. DESIGN Text NRS13_MDC Multi-density categories used in NRSA 2013/14 survey design within a stratum DESIGN Text NRS13_PNL NRSA 2013/14 Panel Assignment DESIGN "Text that has form NRSnn_mmXXXn_YYYY, where nn is current cycle year (07, 12, 17, etc), mm is cycle year stream site was first selected for sampling, XXXn denotes revisit status, and YYYY denotes base or over sample status. XXXN equals either RVT2 (if site should be visited twice in current cycle year) or RVT (if site should be visited once in current cycle and was previously visited in a prior cycle year) and is blank otherwise. YYYY is either blank (if the stream site is a base site) or equals OverSamp (if the stream site is an over sample site). Note: For state specific designs, state two letter code is added." NRS13_SF Lake included/excluded from NRSA 2013/14 survey design DESIGN Exclude|Include | Not Present Blank values are not allowed or NA for missing NRS13_STRA Strata used in NRSA 2013/14 survey design DESIGN Text NRS13_TNT NRS 2013/14 target status assigned based on stream site evaluation for use in national assessments. DESIGN Target | Target_Presumed |Uncertain | Non_Target | Not_Needed | blank NRS13_URBN Stream site identified as an urban or non-urban stream. Source: https://www.census.gov/geo/maps-data/data/cbf/cbf_ua.html. Used 2015 Urban Areas cartographic boundaries shapefile DESIGN NonUrban|Urban NRS13_VST Number of times NRSA 2013/14 site was actually sampled in 2013/14 DESIGN Zero | One | Two Blank is site not evaluated NRS13_WGTD NRSA 2013/14 Initial site weight assigned during site selection. DO NOT USE FOR POPULATION ESTIMATION! DESIGN Numeric: >0 or 0 if site is not to be used for population estimation NRSA_USE Include site in NRSA analyses? DESIGN YES|NO OWN_CODE Land ownership code derived from USGS PADUS (http://gapanalysis.usgs.gov/padus/data/) - pulled May 2016 version of database DESIGN Numeric of 45 detailed PADUS ownership codes; may legitimately by NA if not covered by PADUS owership OWN_DESC Land ownership protective category derived from USGS PADUS (http://gapanalysis.usgs.gov/padus/data/) - pulled May 2016 version of database DESIGN Text of 37 protective category names from PADUS; may legitimately by NA if not covered by PADUS owership OWN_TYPE Basic land ownership category derived from USGS PADUS (http://gapanalysis.usgs.gov/padus/data/) - pulled May 2016 version of database DESIGN Text of 9 basic ownership category names from PADUS; may legitimately by NA if not covered by PADUS owership OWNSHP Detailed land ownership category derived from USGS PADUS (http://gapanalysis.usgs.gov/padus/data/) - pulled May 2016 version of database DESIGN Text of 45 detailed ownership category names from PADUS; may legitimately by NA if not covered by PADUS owership PSTL_CODE State two-letter postal code DESIGN PUBLICATION_DATE Date of data file publication REACHCODE NHD Reach code assigned DESIGN Numeric RT_NRSA "NRSA Reference Class Assignment: R=reference, In=intermediate, Im=impacted, ?=Cannot be evaluated due to missing info" EVAL R|S|T|? SITE_ID Site ID SITETYPE Site type (Probability-based or hand-picked) DESIGN PROB | HAND SO NHD-Plus new Strahler order DESIGN SORT13_ID Design sort ID of site for NRSA 2013-14 survey DESIGN SORT18_ID Design sort ID of site for NRSA 2018-19 survey DESIGN SOURCE Sample frame source DESIGN NHDPlusv2| State frame names STATE State of site STATECTY FIPS state and county code DESIGN Text - numeric with leading zero STATEID State Site ID DESIGN STRAH_CAL Strahler calculator from NHDPlusv2. Used to identify braided reaches. DESIGN Numeric: 0 to 10. STRAH_CAT Strahler category used to classify reaches. RiversMajor (5th and higher) RiversOther (5th and higher) LargeStreams (3rd and 4th) SmallStreams (1st and 2nd) DESIGN RiversMajor | RiversOther | LargeStreams | SmallStreams STRAH_ORD Strahler order from NHDPlusv2 DESIGN Numeric: 0 to 10. STUDY Study to which site belongs DESIGN ALASKA|HAWAII|MSQA|BLM|CALAPOOIA|NRSA|WISCONSIN UID Unique site visit ID US_L3CODE Omernik Level III ecoregion code DESIGN Numeric 1 to 85 US_L3NAME Omernik Level III ecoregion name DESIGN Text name US_L4CODE Omernik Level IV ecoregion code DESIGN Level three codes plus aphabetic ending identifying level 4 subregion US_L4NAME Omernik Level IV ecoregion name DESIGN Text name VISIT_NO Number identifying which visit this is XCOORD x-coordinate from US Contiguous Albers Equal Area Conic projection EXCEPT Hawaii sites which are calculated from Hawaii Albers Equal Area Conic projection DESIGN Numeric YCOORD y-coordinate from US Contiguous Albers Equal Area Conic projection EXCEPT Hawaii sites which are calculated from Hawaii Albers Equal Area Conic projection DESIGN Numeric SITESAMP Site sampled (Y/N) VERIF WGT_EXT_SP Length of sampled streams represented by site in km DESIGN