U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2014–1212

Documentation for the U.S. Geological Survey PublicSupply Database (PSDB)—A Database of Permitted 

Public-Supply Wells, Surface-Water Intakes, and 

Systems in the United States

Documentation for the U.S. Geological 

Survey Public-Supply Database (PSDB)—A 

Database of Permitted Public-Supply 

Wells, Surface-Water Intakes, and Systems 

in the United States

By Curtis V. Price and Molly A. Maupin

Open-File 2014–1212

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Acting Director

U.S. Geological Survey, Reston, Virginia: 2014

For more information on the USGS—the Federal source for science about the Earth, its natural and living 

resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS.

For an overview of USGS information products, including maps, imagery, and publications, 

visit http://www.usgs.gov/pubprod

To order this and other USGS information products, visit http://store.usgs.gov

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the 

U.S. Government.

Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials 

as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.

Suggested citation:

Price, C.V., and Maupin, M.A., 2014, Documentation for the U.S. Geological Survey Public-Supply Database (PSDB)—

A database of permitted public-supply wells, surface-water intakes, and systems in the United States: U.S. Geological 

Survey Open-File Report 2014–1212, 22 p., http://dx.doi.org/10.3133/ofr20141212.

ISSN 2331-1258 (online)
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Data Security.........................................................................................................................................2

Purpose and Scope ..............................................................................................................................2

Development of the Public-Supply Database ...........................................................................................2

Structure and Data Sources for the Public-Supply Database ...............................................................3

Data Tables ............................................................................................................................................3

Systems Data Table (USADRS)..................................................................................................3

Intakes Data Table (USIN)..........................................................................................................3

Wells Data Table (USWL) ...........................................................................................................7

Domain Tables .......................................................................................................................................9

State and StateCounty Domain Tables.....................................................................................9

DirectSourceType, PurchaseSourceType, PurchaseStatus, and CustomerBase

Domain Tables...............................................................................................................12

Availability Domain Table .........................................................................................................12

SiteType Domain Table..............................................................................................................12

LatLonSource, LatLonDetMethod, and LatLonVerifyMethod Domain Tables..................14

Summary........................................................................................................................................................14

References Cited..........................................................................................................................................19

Glossary.........................................................................................................................................................21

Figure

1. Diagram showing the relations between data tables and domain tables in the

Public-Supply Database ..............................................................................................................4
iv

Tables

1. The USADRS data table containing information about public water systems...................5

2. The USIN data table containing information about surface-water facilities .....................6

3. The USWL data table containing information about groundwater facilities......................8

4. The State domain table documenting State codes and ancillary information.................10

5. The StateCounty domain table documenting State-County codes ....................................12

6. The DirectSourceType domain table documenting fields and contents for direct

source types ................................................................................................................................12

7. The PurchaseSourceType domain table documenting fields and contents for

purchase source types ..............................................................................................................13

8. The PurchaseStatus domain table documenting fields and contents for purchase

information...................................................................................................................................13

9. The CustomerBase domain table documenting fields and contents for systems

that supply water for domestic use .........................................................................................13

10. The Availability domain table fields and contents documenting source availability ......14

11. The SiteType domain table documenting fields and contents for site types....................15

12. The LatLonSource domain table documenting location sources.......................................16

13. The LatLonDetMethod domain table documenting location methods ..............................17

14. The LatLonVerifyMethod domain table documenting location verification methods .....18
v

Conversion Factors

SI to inch/pound

Multiply By To obtain

Length

meter 3.281 foot (ft)

kilometer (km) 0.6214 mile (mi)

Inch/Pound to SI (for tables)

Multiply By To obtain

Flow rate

acre-foot per year (acre-ft/yr) 0.001233 cubic hectometer per year (hm3/yr)

gallon per day (gal/d) 0.003785 cubic meter per day (m3/d)

gallon per minute (gal/min) 0.06309 liter per second (L/s)

Abbreviations

CWS community water system (see Glossary)

EPA U.S. Environmental Protection Agency

FIPS Federal Information Processing Standard (see Glossary)

NAWQA National Water-Quality Assessment

NWIS National Water Information System, a database maintained by the 

 U.S. Geological Survey

NWUIP National Water-Use Information Program

PSDB Public-Supply Database, the database documented in this report

PWS public water system (see Glossary)

PwsID Public Water System Identification number (see Glossary)

SDWA Safe Drinking Water Act

SDWIS Safe Drinking Water Information System; the aggregated Federal database 

 is sometimes referred to as SDWIS/FED

USADRS data table used in the Public-Supply Database for systems

USGS U.S. Geological Survey, a Bureau of the U.S. Department of the Interior

USIN data table used in the Public-Supply Database for intakes 

USWL data table used in the Public-Supply Database for wells

WBD Watershed Boundary Dataset
vi
Documentation for the U.S. Geological Survey PublicSupply Database (PSDB)—A Database of Permitted 

Public-Supply Wells, Surface-Water Intakes, and Systems 

in the United States

By Curtis V. Price and Molly A. Maupin

Abstract

The U.S. Geological Survey (USGS) has developed a 

database containing information about wells, surface-water 

intakes, and distribution systems that are part of public 

water systems across the United States, its territories, and 

possessions. Programs of the USGS such as the National 

Water Census, the National Water Use Information Program, 

and the National Water-Quality Assessment Program all 

require a complete and current inventory of public water 

systems, the sources of water used by those systems, and the 

size of populations served by the systems across the Nation. 

Although the U.S. Environmental Protection Agency’s Safe 

Drinking Water Information System (SDWIS) database 

already exists as the primary national Federal database for 

information on public water systems, the Public-Supply 

Database (PSDB) was developed to add value to SDWIS 

data with enhanced location and ancillary information, and 

to provide links to other databases, including the USGS’s 

National Water Information System (NWIS) database.

The purpose of this report is to document the PSDB and 

explain the methods used to populate and update the data 

from the SDWIS, State datasets, and map and geospatial 

imagery. This report describes 3 data tables and 11 domain 

tables, including field contents, data sources, and relations 

between tables. Although the PSDB database is not available 

to the general public, this information should be useful for 

others who are developing other database systems to store and 

analyze public-supply system and facility data.

Introduction

The Federal government has had the responsibility of 

protection the quality of the Nation’s drinking-water supply 

for decades. The U.S. Department of Health inventoried 

large public water suppliers in the years before the 

U.S. Environmental Protection Agency (EPA) was assigned 

those responsibilities under the auspices of the Safe Drinking 

Water Act (SDWA). The SDWA originally was passed in 1974, 

and was later amended in 1986 and 1996 with requirements to 

protect drinking-water sources such as lakes, rivers, reservoirs, 

springs, and groundwater. The SDWA is the main Federal law 

that ensures the quality of drinking water in the United States, 

its territories, and possessions (U.S. Environmental Protection 

Agency, 2014a). The EPA enforces Federal standards and 

requires State, local, and private water suppliers to implement 

the standards in their practices of water deliveries to the 

public. A public water system (PWS) is strictly defined under 

the SDWA as a system capable of providing water for human 

consumption through pipes or other constructed conveyances 

to at least 15 service connections, or to at least 25 individuals, 

for at least 60 days per year (U.S. Environmental Protection 

Agency, 2014b).

Two major responsibilities of the EPA Office of Ground 

Water and Drinking Water under the SDWA are to (1) set 

national standards for drinking-water quality and (2) to 

ensure that the States that have assumed primary enforcement 

responsibility (“primacy”) are complying with these standards 

(U.S. Environmental Protection Agency, 2014a). In support of 

this program, the EPA has developed the Safe Drinking Water 

Information System (SDWIS) for States to store information 

on PWSs (U.S. Environmental Protection Agency, 2014c):

The Safe Drinking Water Information System 

contains information about public water systems 

and their violations of EPA’s drinking water 

regulations. These statutes and accompanying 

regulations establish maximum contaminant levels, 

treatment techniques, and monitoring and reporting 

requirements to ensure that water provided to 

customers is safe for human consumption.

Although the SDWIS database is a comprehensive 

national database of PWSs and their facilities, the database 

has limitations for use in assessing water use because it is an 

aggregation of local information developed by State, Tribal, 

and local community agencies, and it focuses primarily on 
2 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

population size and water-quality measures with regards to 

compliance and violations. Therefore, it lacks water withdrawal 

data for a specific facilities (surface-water intakes or wells). 

Local databases are uploaded to the national SDWIS database 

by the individual agencies, or by the EPA Regions when a State 

or Tribal entity does not have primacy. Because the SDWIS 

represents an aggregation of local database information 

developed from many sources, it is important as a nationalscale collection of water facility information. However, the 

quality, consistency, and existence of facility location, and 

ancillary data in the SDWIS can be highly variable.

The U.S. Geological Survey (USGS) originally 

developed the Public-Supply Database (PSDB) to enhance 

the structure and content of information available from 

SDWIS, adding value to the data to improve its usefulness 

for USGS studies. Much of this development was supported 

by the USGS National Water-Quality Assessment (NAWQA) 

Program (Gilliom and others, 2001), which required sitespecific water-use information for many of its studies and 

initiatives. The PSDB also was used to link USGS sampling 

sites to the SDWIS database and other hydrologic datasets.

The PSDB also has become an important resource for 

national assessments of water use. The Omnibus Public 

Land Management Act of 2009 (Public Law 111‒11), and 

specifically Subtitle F, also known as the “SECURE Water 

Act,” made recommendations for the establishment of a 

national water availability and use assessment program 

within the USGS. The primary need for this recommendation 

was to complete a national assessment of water use, which 

had not been done since 1978 (Alley and others, 2013). 

The USGS began implementing the “SECURE Water Act” 

recommendations in 2011 by the development of a new 

program, the National Water Census (“Water Census”). The 

Water Census aims to develop and improve water accounting 

tools and assess water availability at the regional and national 

scales (U.S. Geological Survey, 2014a). Additionally, USGS 

has provided water-use estimates and trends analysis for 

the Nation as part of the National Water-Use Information 

Program (NWUIP; U.S. Geological Survey, 2014b), which 

has reported water use in the United States every 5 years since 

1950 (MacKichan, 1951, 1957; MacKichan and Kammerer, 

1961; Murray, 1968; Murray and Reeves, 1972, 1977; Solley 

and others, 1983, 1988, 1993, 1998; Hutson and others, 2004, 

Kenny and others, 2009). The NWUIP is an integral part of the 

Water Census. The Water Census has identified development 

of site-specific public-supply water-use data as one of its 

initial areas of focus required to achieve its objectives. Before 

the inception of the Water Census, NWUIP had not developed 

national site-specific data for PWSs and facilities, and 

depended largely on areal estimates of aggregate water use 

(commonly at the County level).

The USGS National Water Information System (NWIS; 

Dupré and others, 2013) stores many types of water data 

(for example, groundwater levels, surface-water flows, water 

quality, and water use). As part of Water Census activities and 

using PSDB data, the number of new sites in the NWIS has 

increased in an effort to build a comprehensive national set of 

site-specific data for PWSs and their facilities. Data collected 

as part of the NWUIP, such as withdrawals and deliveries 

to customers, are being stored in NWIS as the data become 

available. The PSDB has become a critical resource for the 

development of site-specific water-use information for the 

NWIS database that will be used by Water Census and the 

NWUIP.

Data Security

The location information for PWSs is restricted by the 

EPA from distribution to the general public, but was made 

available to USGS through a USGS–EPA memorandum 

of understanding that adheres to data sharing policies with 

respect to PWS site information. The content of PSDB would 

be available to any entity that had a similar data-sharing 

agreement with the EPA.

Purpose and Scope

The PSDB is a national dataset that includes information 

about wells, surface-water intakes, and distribution systems 

that are part of PWSs across the United States. The PSDB 

contains data from the EPA SDWIS. The purpose of this report 

is to document the PSDB and explain the methods used to 

populate and update the data from the SDWIS, State datasets, 

maps, and geospatial imagery. This report describes 3 data 

tables and 11 domain tables, including field contents, data 

sources, and relations between tables. Although the PSDB 

database is not available to the general public, the contents of 

this report may be useful for others who are developing other 

database systems to store and analyze public-supply system 

and facility data.

Development of the Public-Supply 

Database

The first version of PSDB was a cooperative effort 

between EPA and USGS in 1997. Data about PWSs were 

retrieved from the SDWIS as part of a USGS–EPA project 

evaluating the effects of changing the maximum allowable 

levels of arsenic in drinking water (Focazio and others, 1999). 

The SDWIS system and facility records were reorganized 

into three main tables for PWSs; the tables were composed of 

information about systems, wells, and surface-water intakes. 

Missing system information was updated from State sources.

The PSDB was used for a second USGS‒EPA project 

that required the referencing of PWS intakes to the EPA River 

Reach File Version 1 stream network dataset (Alexander 

and others, 1999). Quality-assured locational information 

was needed for this project to make it possible to assign 

reference numbers to each intake. Commercial off-the-shelf 
Structure and Data Sources for the Public-Supply Database 3

digital mapping software (DeLorme Street Atlas USA; 

DeLorme, 2014) was used to verify the accuracy of latitude 

and longitudes in the PSDB. The USGS Water Science 

Centers requested location information (when surface-water 

intake locations were missing from the SDWIS) from State 

agencies, NWIS, or through direct contact with PWS owners. 

The details of how the locations were verified or changed are 

documented using text fields in the data tables and using codes 

documented in associated domain tables.

The USGS NAWQA Program supported an effort to 

validate locations for surface-water sources in the PSDB for 

PWSs serving less than 10,000 people. The PSDB became an 

important source of data for planning and prioritizing a variety 

of NAWQA studies. In late 2000, the EPA and USGS began 

collaborating on an effort to develop a single set of reliable 

intake locations that would reside in the SDWIS. Staff of the 

USGS provided results of their quality-control work to the 

EPA, who in turn forwarded the information to State staff 

responsible for updating State or local data into the SDWIS. 

Subsequent retrievals (the latest in 2010) were used to update 

the PSDB with new facility and system information.

Structure and Data Sources for the 

Public-Supply Database

The PSDB consists of 3 data tables supported by 

11 domain tables (fig. 1). Relations are defined to link the data 

tables and domain tables.

The PSDB contains two main types of tables—data tables 

and domain tables. Data tables contain information from the 

SDWIS, additional information added from other sources, 

derived fields, and fields used to track updates. The data tables 

are supported by domain tables that promote uniformity by 

providing a list of valid field values and, in many cases, text 

description fields describing the values. Domain tables also are 

used to provide additional ancillary information. Two special 

kinds of fields exist in these tables—a primary key field in 

a table uniquely identifies each row, and its value can be 

accessed by another table to act as a foreign key field to link 

rows across tables. Detailed descriptions of the PSDB data and 

domain tables are included in this report.

Because the SDWIS historically did not include a 

permanent unique identifier for each facility, the PSDB 

includes an identifier that is used to track information about 

facilities in the PSDB, and enables reconciliation between 

updates from SDWIS retrievals provided by EPA. Location 

data from the SDWIS were evaluated and updated using 

information from other sources, if found to be invalid or failed 

an accuracy check. Other locational information and ancillary 

data developed during the course of several USGS‒EPA 

projects also were added to the PSDB. Where a match was 

identified between the PSDB well facilities and public-supply 

well sites in the NWIS database, the NWIS unique station 

identifier was recorded in the PSDB. Additionally, inquiries 

with State and Federal agencies provided unique identifiers 

that are used to relate facilities between NWIS, SDWIS, and 

State databases.

Data Tables

Three main data tables are included in the PSDB. The 

USADRS data table contains records corresponding to 

public water-supply systems (“systems”). The USIN data 

table includes records for surface-water facilities (“intakes”), 

and the USWL data table contains records for groundwater 

facilities (“wells”). The USADRS is the “parent” data table 

for the USIN and USWL data tables, and provides the 

Public Water System Identification number (PwsID), which 

is an identifying code that associates intakes and wells to a 

particular water system.

Systems Data Table (USADRS)

The USADRS data table contains information on 

public water-supply systems (table 1). Nine data fields were 

originally imported from the SDWIS; two of the eight SDWIS 

fields (noted in table 1 with the code “S”) are kept up to date 

with SDWIS, and six of the eight fields (noted in table 1 

with the code “M”), although originally imported from the 

SDWIS, may have been modified using other sources. The 

remaining data fields have been created to record non-SDWIS 

water-resource and database maintenance information. 

These field values are either derived from other fields or 

have been populated from non-SDWIS sources. Six domain 

tables serve the USADRS table data: State, StateCounty, 

DirectSourceType, PurchSourceType, PurchaseStatus, 

and CustomerBase. All of these tables are described in the 

“Domain Tables” section.

Intakes Data Table (USIN)

The USIN data table (table 2) contains information 

about surface-water facilities (“intakes”). Ten data fields were 

originally imported from the SDWIS; 6 of the 10 SDWIS 

fields (noted in table 2 with the code “S”) are kept up to 

date with the SDWIS, and 4 of the 10 fields (noted in table 2 

with the code “M”), although originally imported from the 

SDWIS, may have been modified using other sources. The 

rest of the field values either are derived from other fields or 

have been populated from non-SDWIS sources. In addition to 

the PwsID field that links (as a foreign key) to the USADRS 

data table, seven domain tables serve the USIN data table: 

State, StateCounty, Availability, SiteType, LatLonSource, 

LatLonDetMethod, and LatLonVerifyMethod. All of these 

tables are described in the “Domain Tables” section.
4 Documentation for the U.S. Geological Survey Public-Supply Database in the United States Availability (see table 10) Availability_ID SiteType (see table 11) SiteType_ID LatLonSource (see table 12) LatLonSource_ID LatLonDetMethod (see table 13) LatLonDetMethod_ID LatLonVerifyMethod (see table 14) LatLonVerifyMethod_ID DirectSourceType (see table 6) PurchaseSourceType (see table 7) DirectSrceType_ID PurchaseSrceType_ID PurchaseStatus (see table 8) PurchaseStatus_ID CustomerBase (see table 9) CustomerBase_ID PwsID PCountyCode PStateCode DirectSrceType_ID PurchaseSrceType_ID PurchaseStatus_ID CustomerBase_ID USADRS (public water- supply systems, see table 1) StateCounty (State-County codes, see table 5) CountyCode State (State codes, see table 4) and StateCounty (State-County codes, see table 5) StateCode StatePostal USIN (surface-water intakes, see table 2) PwsSrce_ID PwsID State Availability_ID SiteType_ID LatLonSource_ID LatLonDetMethod_ID LatLonVerifyMethod_ID LatLonCounty USWL (wells, see table 3) PwsSrce_ID PwsID State Availability_ID SiteType_ID LatLonSource_ID LatLonDetMethod_ID LatLonVerifyMethod_ID LatLonCounty EXPLANATION Data table Domain table One-to-many relation Table Name Field name Table Name Field name Figure 1. Relations between data tables and domain tables in the Public-Supply Database (PSDB). Only table fields used as keys to join related tables 

are shown; other fields are not included.
Structure and Data Sources for the Public-Supply Database 5

Table 1. The USADRS data table containing information about public water-supply systems.

[This data table contained 64,103 records as of August 1, 2014. *, primary key; +, foreign key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); EPA, U.S. Environmental Protection Agency; PWS, public water system; FIPS, Federal Information Processing Standard 

(U.S. Bureau of the Census, 2002, 2014); CWS, community water system; NWIS, National Water Information System (Dupré and others, 2013); ID, identification number; WBD, Watershed Boundary Dataset (U.S. Geological Survey and U.S. Department of Agriculture, Natural Resources Conservation Service, 2013); 

--, not applicable]

Field name SDWIS

field1

Field

fype Associated domain Description

PwsID* S Text -- EPA PWS number.

SystemName M Text -- Name of community water system.

Address M Text -- Contact address.

City M Text -- Contact city.

State+ M Text State (table 4) Contact State (postal code).

ZipCode M Text -- Contact zip code.

Phone M Text -- Contact phone number.

PCountyCode+ S Text CountyCode (table 5) FIPS State-County code for system’s primary service area. 

(Derived from the SDWIS PCounty field).

PStateCode+ -- Text State (table 4) FIPS State code of system.

PWSType -- Text -- Public water-supply type, from the SDWIS: CWS, Community water system; NTNCWS, non-transient, non-community 

water system, TNCWS: transient community water system; 

null, unknown.

PopulationServed S Float -- Population served by system from the SDWIS.

AdjPopulationServed -- Float -- Value to be used in place of the SDWIS value (PopulationServed).

PopulationNotes -- Text -- Notes about PopulationServed and AdjPopulationServed 

values.

DirectSrceType_ID+ -- Text DirectSourceType (table 6) Code identifying types of sources a CWS controls directly.

PurchaseSrceType_ID+ -- Text PurchSourceType (table 7) Code identifying the sources of water purchased by community water systems.

Notes -- Text -- Notes about sources.

PurchaseStatus_ID+ -- Text PurchaseStatus (table 8) Code that records status of system as a purchaser and/or seller 

of water.

CustomerBase_ID+ -- Text CustomerBase (table 9) Code that identifies systems whose customer base includes 

only domestic users. 

InactiveFlag -- Text -- Y, the system is considered inactive (not included in the 

SDWIS retrieval of active sites); N, the system is included 

in the SDWIS retrieval of active sites.

PSDB_SWUDS_SiteID -- Text -- Proposed NWIS site number.

PSDB_SWUDS_SiteName -- Text -- Proposed NWIS site name.

NWIS_AgencyCode -- Text NWIS NWIS agency code.

NWIS_SiteID -- Text NWIS NWIS site number.

NWIS_SiteName -- Text NWIS NWIS site name.

PHUC8 -- Text WBD 8-digit WBD watershed code, determined from overlap of 

primary service area County with WBD boundary polygons.

DateModified -- Date -- Date this record was last modified.

1

S, field value originally imported from the SDWIS, updated only from subsequent SDWIS retrievals; M, field value originally populated from the SDWIS, 

but may be modified using other sources; --, field values not from the SDWIS.
6 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Table 2. The USIN data table containing information about surface-water facilities (“intakes”).

[This data table contained 11,400 records as of August 1, 2014. *, primary key, +, foreign key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); PSDB, Public-Supply Database; ID, identification number; EPA, U.S. Environmental Protection Agency; PWS, public 

water system; FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 2002, 2014); USGS, U.S. Geological Survey; NWIS, National Water 

Information System (Dupré and others, 2013); --, not applicable]

Field name SDWIS

field1

Field

type Associated domain Description

PwsSrce_ID* -- Integer -- PSDB source ID (unique USIN and USWL data tables).

PwsID+ S Text USADRS (table 1) EPA PWS number.

FacID+ S Text -- SDWIS facility ID (unique match to the SDWIS by dual keys 

PwsID + FacID).

State+ -- Text State (table 4) State (postal code) of system owner.

FacilityName S Text -- SDWIS facility name (FacName).

SourceName -- Text -- Name of source (for example, the name of a a river, stream, or 

lake).

SourceType S Text -- SDWIS facility type code (FacTypeCode): CC, Consecutive_connection; CH, Common_headers; CS, Cistern; CW, Clear_well; 

DS, Distribution_system_zone; IG, Infiltration_gallery; IN, 

Intake; NP, Non-piped; OT, Other; PC, Pressure_control; 

PF, Pump_facility; RC, Roof_catchment; RS, Reservoir; SI, 

Surface_impoundment; SP, Spring; SS, Sampling_station; ST, 

Storage; TM, Transmission_main; TP, Treatment_plant; WH, 

Well_head; WL, Well.

SourceWaterType S Text -- SDWIS water type (FacWaterType): GU, groundwater under the 

influence of surface water; GW, groundwater; SW, surface 

water.

Availability_ID+ S Text Availability (table 10) Text code denoting SDWIS temporal availability (Availability).

SiteType_ID+ -- Integer SiteType (table 11) Integer code denoting type of water source.

Latitude -- Text -- Latitude in text format “DDMMSS” (degrees, minutes, seconds).

Longitude -- Text -- Longitude in text format “DDDMMSS” (degrees, minutes, seconds).

LatDD M Float -- Latitude in decimal degrees.

LonDD M Float -- Longitude in decimal degrees (west longitude as negative value).

LatLonDatum M Text -- Horizontal datum: NAD27, North American Datum of 1927; 

NAD83, North American Datum of 1983; WGS84, World Geodetic System 1984; null, unknown.

LatLonValid -- Yes/No -- Yes (true) if location is a valid latitude-longitude.

LatLonSource_ID+ -- Text LatLonSource 

(table 12)

Text code denoting source of latitude/longitude value.

LatLonDetMethod_ID+ M Text LatLonDetMethod

(table 13)

Text code denoting method used to determine latitude/longitude 

value. These codes are based on EPA standard method codes 

used in the SDWIS (Environmental Data Standards Council, 

2006) with additions specific to PSDB (foreign key to USIN 

[table 2] and USWL [table 3]).

LatLonVerifyMethod_ID+ -- Integer LatLonVerifyMethod

(table 14)

Integer code denoting method used to verify latitude/longitude 

value.

NotesOnPSDBLocation -- Text -- Notes on location in PSDB that is different from SDWIS location.

NotesOnSDWISLocation -- Text -- Notes on incorrect SDWIS location.

LatLonCounty+ -- Text CountyCode (table 5) State and County (FIPS) code in which surface-water source is 

located.
Structure and Data Sources for the Public-Supply Database 7

Wells Data Table (USWL)

The USWL data table (table 3) contains information 

about the groundwater facilities (“wells”). These records 

include wells, well fields, and other types of facilities, such as 

springs and cisterns. Ten data fields were originally imported 

from the SDWIS; 6 of the 10 SDWIS fields (noted in table 

2 with the code “S”) are kept up to date with the SDWIS, 

and 4 of the 10 fields (noted in table 2 with the code “M”), 

although originally imported from the SDWIS, may have 

been modified using other sources. The rest of the field values 

either are derived from other fields or have been populated 

from non-SDWIS sources. In addition to the PwsID field that 

links (as a foreign key) to the USADRS data table, seven 

domain tables serve the USIN data table: State, StateCounty, 

Availability, SiteType, LatLonSource, LatLonDetMethod, and 

LatLonVerifyMethod, which are described in the “Domain 

Tables” section.

Location information stored in the USIN and USWL 

tables were reviewed and updated to enhance the information 

available from the SDWIS. During 2004, the USGS NAWQA 

Program and the EPA quality-assured SDWIS well location 

data. The location for each well was plotted to examine 

its location with respect to the County recorded in the 

SDWIS. Wells whose locations were within the County were 

documented as valid, and wells that were within 1,000 meters 

of the County line were noted as outside, but valid. All well 

locations that plotted outside the County line by more than 

1,000 meters were investigated to determine if updates to the 

location were needed. If the location did not overlap with the 

County that was recorded in the SDWIS, but belonged to a 

large PWS that presumably would provide water to multiple 

counties, the well was documented as valid. Otherwise, a 

new location was developed for the well based on a variety 

of available methods. Finally, the sites from the PSDB were 

compared with USGS NWIS groundwater sites. USGS site 

identification numbers were recorded in the PSDB for wells 

that could be matched between the two databases. The same 

procedures were applied to intakes, and the PSDB was 

updated to record the results of these quality-assurance efforts.

Table 2. The USIN data table containing information about surface-water facilities (“intakes”).—Continued

[This data table contained 11,400 records as of August 1, 2014. *, primary key, +, foreign key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); PSDB, Public-Supply Database; ID, identification number; EPA, U.S. Environmental Protection Agency; PWS, public 

water system; FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 2002, 2014); USGS, U.S. Geological Survey; NWIS, National Water 

Information System (Dupré and others, 2013); --, not applicable]

Field name SDWIS

field1

Field

type Associated domain Description

HUC12 -- Text WBD 12-digit WBD watershed, determined from overlap of site location 

with WBD boundary polygons (U.S. Geological Survey and 

U.S. Department of Agriculture, Natural Resources Conservation Service, 2013).

AreaSqmi -- Float -- Drainage area, from 2011 NHDPlus analysis (Michael Wieczorek, 

U.S. Geological Survey, oral commun., 2012).

Notes -- Text -- Other notes on site.

PSDB_SWUDS_Site_ID -- Text -- Proposed NWIS site number.

PSDB_SWUDS_SiteName -- Text -- Proposed NWIS site name.

NWIS_AgencyCode -- Text NWIS NWIS agency code.

NWIS_SiteID -- Text NWIS NWIS site number.

NWIS_SiteName -- Text NWIS NWIS site name.

StateID -- Text -- Source identifier used by State agency.

InactiveFlag -- Text -- Y, the site is considered inactive (not included in the SDWIS 

retrieval of active sites); N, the site is included in the SDWIS 

retrieval of active sites.

NotAnIntake -- Text -- Y, the site is tagged as not an intake (for example, conveyance, 

misclassified well); N, the site has not been tagged as not an 

intake.

DuplicateSite -- Text -- Y, the site is tagged as a duplicate of another SDWIS facility; N, 

the site is not tagged as a duplicate.

DateModified -- Date/Time -- Date this record was last modified (working field).

1

S, field value originally imported from the SDWIS, updated only from subsequent SDWIS retrievals; M, field value originally populated from the SDWIS, 

but may be modified using other sources; --, field values not from the SDWIS.
8 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Table 3. The USWL data table containing information about groundwater facilities (“wells”).

[This data table contained 147,775 records as of August 1, 2014. *, primary key, +, foreign key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); PSDB, Public-Supply Database; ID, identification number; EPA, U.S. Environmental Protection Agency; PWS, public 

water system; FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 2002, 2014); USGS, U.S. Geological Survey; NWIS, National Water 

Information System (Dupré and others, 2013); --, not applicable]

Field name SDWIS

field1

Field

type Associated domain Description

PwsSrce_ID* -- Integer -- PSDB Source ID (unique between USIN and USWL data tables).

PwsID+ S Text USADRS

(table 1)

EPA PWS number.

FacID S Text -- SDWIS facility ID (unique match to the SDWIS by dual keys PwsID + 

FacID).

State+ -- Text State (table 4) State (postal code) of system owner.

SDWIS_ID S Integer -- Original SDWIS internal_id for facility (tinwsf_is_number).

FacilityName S Text -- SDWIS source name (FacName).

SourceName -- Text -- Name of source.

SourceType S Text -- SDWIS facility type code (FacTypeCode): CC, Consecutive_connection; CH, Common_headers; CS, Cistern; CW, Clear_well; DS, 

Distribution_system_zone; IG, Infiltration_gallery; IN, Intake; NP, 

Non-piped; OT, Other; PC, Pressure_control; PF, Pump_facility; 

RC, Roof_catchment; RS, Reservoir; SI, Surface_impoundment; SP, 

Spring; SS, Sampling_station; ST, Storage; TM, Transmission_main; 

TP, Treatment_plant; WH, Well_head; WL, Well.

SourceWaterType S Text -- SDWIS water type (FacWaterType): GU, groundwater under the influence of surface water; GW, groundwater; SW, surface water.

Availability_ID S Text Availability (table 10) SDWIS temporal availability code (Availability).

StateSource_ID -- Text Source ID used by State agency.

SiteType_ID+ -- Integer SiteType (table 11) Integer key which uniquely identifies type of water source.

LatDD M Float -- Latitude in decimal degrees.

LonDD M Float -- Longitude in decimal degrees.

LatLonDatum M Text -- Horizontal datum: NAD27, North American Datum of 1927; NAD83, 

North American Datum of 1983; WGS84, World Geodetic System 

1984; null, unknown.

Latitude -- Text -- Latitude in text format “DDMMSS” (degrees, minutes, seconds).

Longitude -- Text -- Longitude in text format “DDDMMSS” (degrees, minutes, seconds).

LatLonValid -- Yes/

No

-- True if valid LatDD and LonDD.

LatLonSource_ID+ M Text LatLonSource 

(table 12)

Source of latitude/longitude.

LatLonDetMethod_ID+ M Text LatLonDetMethod

(table 13)

Text code denoting method used to determine latitude/longitude value. 

These codes are based on EPA standard method codes used in the 

SDWIS These codes are based on EPA standard location method 

codes, with PSDB additions.

LatLonVerifyMethod_ID+ -- Text LatLonVerifyMethod

(table 14)

Integer code denoting method used to verify latitude/longitude value.

NotesOnSDWISLocation -- Text -- Notes on incorrect SDWIS location.

NotesOnPSDBLocation -- Text -- Notes on location in PSDB that is different from SDWIS location.

LatLonCounty -- Text CountyCode (table 5) State and County (FIPS code) in which groundwater source is located.

HUC12 -- -- WBD 12-digit Watershed Boundary Dataset (WBD) watershed, determined from overlap of site location with WBD boundary polygons 

(U.S. Geological Survey and U.S. Department of Agriculture, Natural 

Resources Conservation Service, 2013).
Structure and Data Sources for the Public-Supply Database 9

Domain Tables

The PSDB includes 11 domain tables (fig. 1): State, 

StateCounty, DirectSourceType, PurchaseSourceType, 

PurchaseStatus, CustomerBase, Availability, SiteType, 

LatLonSource, LatLonDetMethod, and LatLonVerifyMethod. 

These domain tables are used to document codes used in the data 

tables, and verify that all codes used in the data tables are valid. 

In addition, these domain tables can be used to build efficient 

database queries to extract or group records from the database.

State and StateCounty Domain Tables

The domain tables for State (table 4) and StateCounty 

(table 5) list State and County codes and names. All three 

data tables (USADRS, USIN, and USWL) use these codes to 

denote State and County areas. In addition, the State table was 

used to record ancillary data on permitting policies in effect 

in these States and primary time zones. These ancillary fields 

have not been verified for accuracy against current State laws 

and policies.

Table 3. The USWL data table containing information about groundwater facilities (“wells”).—Continued

[This data table contained 147,775 records as of August 1, 2014. *, primary key, +, foreign key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); PSDB, Public-Supply Database; ID, identification number; EPA, U.S. Environmental Protection Agency; PWS, public 

water system; FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 2002, 2014); USGS, U.S. Geological Survey; NWIS, National Water 

Information System (Dupré and others, 2013); --, not applicable]

Field name SDWIS

field1

Field

type Associated domain Description

Notes -- -- -- Other notes on site.

PSDB_SWUDS_SiteID -- -- -- Proposed NWIS site ID.

PSDB_SWUDS_SiteName -- -- -- Proposed NWIS site name.

NWIS_AgencyCode -- -- NWIS NWIS agency code.

NWIS_SiteID -- -- NWIS NWIS site number.

NWIS_SiteName -- -- NWIS NWIS site name.

StateLocal_ID -- -- -- State agency name or identifier for well.

StateWellDepth -- -- -- Well depth provided by State agency.

StateTopOfScreen -- -- -- Top of screen from State database.

StateBottomOfScreen -- -- -- Bottom of screen from State database.

StateConstDate -- -- -- Date of well construction from State database as YYYYMMDD (year, 

month, day).

InactiveFlag -- -- -- Y, the site is considered inactive (not included in the SDWIS retrieval 

of active sites); N, the site is included in the SDWIS retrieval of active sites.

NotAWell -- -- -- Y, the site is tagged as not a well (for example, conveyance, misclassified intake); N, the site has not been tagged as not a well. 

DuplicateSite -- -- -- Y, the site is tagged as a duplicate of another SDWIS facility; N, the site 

is not tagged as a duplicate.

DateModified -- -- -- Date this record was last modified (working field).

1

S, field value originally imported from the SDWIS, updated only from subsequent SDWIS retrievals; M, field value originally populated from the SDWIS, 

but may be modified using other sources; --, field values not from the SDWIS.
10 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Table 4. The State domain table documenting State codes and ancillary information.

[This data table contained 61 records as of August 1, 2014. This domain table serves the USADRS, USIN, 

and USWL data tables. *, primary key; FIPS, Federal Information Processing Standard (U.S. Bureau of the 

Census, 2002, 2014); (null), no data available; gal/d, gallons per day; gal/min, gallons per minute; acre-ft/yr, 

acre-feet per year]

Field name Field

type Description

StateCode* Integer Two-digit FIPS State code.

StatePostal Text State postal code.

StateName Text Name of State or Territory.

Registration Text Notes on community water system registration rules for a State.

Permitting Text Notes on community water system permitting rules for a State.

Reporting Text Notes on required reporting period for a State.

Table contents:

StateCodeStatePostal StateName Registration Permitting Reporting

01 AL Alabama (null) 100,000 gal/d monthly

02 AK Alaska (null) 1,500 gal/d monthly

03 AZ Arizona (null) variable (null)

04 AR Arkansas (null) 50,000 gal/d monthly

06 CA California (null) variable (null)

08 CO Colorado (null) variable (null)

09 CT Connecticut (null) 50,000 gal/d monthly to annual

10 DE Delaware (null) 50,000 gal/d monthly

11 DC Washington D.C. (null) (null) (null)

12 FL Florida (null) variable (null)

13 GA Georgia (null) 100,000 gal/d (null)

15 HI Hawaii (null) 1,000 gal/d monthly

16 ID Idaho (null) 108 gal/min (null)

17 IL Illinois (null) (null) (null)

18 IN Indiana 100,000 gal/d (null) monthly

19 IA Iowa (null) 25,000 gal/d (null)

20 KS Kansas (null) all monthly

21 KY Kentucky (null) 10,000 gal/d at least 2 times per year

22 LA Louisiana (null) 1,000,000 gal/d at least 4 times per year

23 ME Maine (null) all monthly

24 MD Maryland (null) 10,000 gal/d 2 times per year

25 MA Massachusetts (null) 100,000 gal/d monthly

26 MI Michigan (null) 100,000 gal/d monthly

27 MN Minnesota (null) 10,000 gal/d monthly

28 MS Mississippi (null) all annual

29 MO Missouri 100,000 gal/d (null) annual

30 MT Montana (null) variable (null)

31 NE Nebraska (null) variable (null)

32 NV Nevada (null) variable variable

33 NH New Hampshire 20,000 gal/d (null) monthly
Structure and Data Sources for the Public-Supply Database 11

Table 4. The State domain table documenting State codes and ancillary information.—Continued

[This data table contained 61 records as of August 1, 2014. This domain table serves the USADRS, USIN, and USWL data 

tables. *, primary key; FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 2002, 2014); (null), no 

data available; gal/d, gallons per day; gal/min, gallons per minute; acre-ft/yr, acre-feet per year]

StateCodeStatePostal StateName Registration Permitting Reporting

34 NJ New Jersey (null) 100,000 gal/d monthly

35 NM New Mexico (null) all quarterly or annual

36 NY New York (null) variable variable

37 NC North Carolina (null) variable variable

38 ND North Dakota (null) all annual

39 OH Ohio (null) 100,000 gal/d annual

40 OK Oklahoma (null) all annual

41 OR Oregon (null) 15,000 gal/d monthly

42 PA Pennsylvania (null) variable variable

44 RI Rhode Island (null) 100,000 gal/d variable

45 SC South Carolina (null) 100,000 gal/d quarterly

46 SD South Dakota (null) all variable

47 TN Tennessee (null) (null) monthly

48 TX Texas (null) variable variable

49 UT Utah (null) 20 acre-ft/yr annual

50 VT Vermont (null) (null) (null)

51 VA Virginia (null) 10,000 gal/d monthly

53 WA Washington (null) (null) no

54 WV West Virginia (null) (null) no

55 WI Wisconsin (null) all annual

56 WY Wyoming (null) variable variable

60 AS American Samoa (null) (null) (null)

64 FM Federated States of Micronesia (null) (null) (null)

66 GU Guam (null) (null) (null)

68 MH Marshall Islands (null) (null) (null)

69 MP Northern Mariana Islands (null) (null) (null)

70 PW Palau (null) (null) (null)

72 PR Puerto Rico (null) (null) (null)

74 UM U.S. minor outlying islands (null) (null) (null)

78 VI U.S. Virgin Islands (null) (null) (null)

NN NN Navajo Nation (null) (null) (null)
12 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

DirectSourceType, PurchaseSourceType, 

PurchaseStatus, and CustomerBase Domain 

Tables

The three domain tables that document codes used in the 

PSDB to describe characteristics of PWSs in USADRS are 

DirectSourceType (table 6), PurchaseSourceType (table 7), 

and PurchaseStatus (table 8). These domain tables are 

assigned based on analysis of the relations between systems 

(USADRS), intakes (USIN), and wells (USWL). When these 

three data tables are joined together, the number of wells and 

intakes associated with each system can be counted. These 

counts have been used to classify USADRS records by the 

number of associated direct sources (wells and intakes). 

The SDWIS also includes information recording possible 

transfers between systems (system-to-system conveyances) 

that has been included in this analysis to identify systems 

that appear (based on the information in the SDWIS) to only 

purchase water from other systems and classifies them using 

the PurchaseSource domain (table 8). The CustomerBase 

domain table (table 9) documents the codes describing systems 

that only service domestic users for systems that have been 

evaluated to determine this information.

Availability Domain Table

The Availability domain table (table 10) serves the 

USIN and the USWL data tables. Public water supplies 

sometimes use wells or intakes occasionally or seasonally. 

The SDWIS database includes a data field (Availability) that 

describes when a water source is available for use. In the 

PSDB, this information is intermittently updated to match the 

most recently available version of the SDWIS; in the PSDB, 

the SDWIS value has been converted to a single-character 

alphabetic code for ease of use (table 10).

SiteType Domain Table

The SiteType domain table (table 11) serves both the 

USIN and the USWL data tables, and in the PSDB, refers to 

the water source classification. In many cases, a site type used 

for a water source can be assigned based on the source name 

provided in the SDWIS. Most SDWIS site types correspond 

directly to site types used in the USGS NWIS database. A set 

of codes were developed for the PSDB to record these site 

types. In addition to the PSDB codes, the SiteType domain 

table lists (if possible) corresponding site types used in the 

USGS NWIS database. The site type code “0” (“unknown”) is 

used for sites for which the site type could not be determined.

Table 5. The StateCounty domain table documenting StateCounty codes.

[This data table1 contained 3,224 records as of August 1, 2014. This domain 

table serves the USADRS, USIN, and USWL data tables. *, primary key; 

FIPS, Federal Information Processing Standard (U.S. Bureau of the Census, 

2002, 2014)]

Field name Field

type Description

CountyCode* Integer Five-digit FIPS State-County code.

StateCode Text Two-digit FIPS State code.

StatePostal Text State postal code.

StateName Text State name.

CountyName Text County name.

TimeZone Text County time zone.

1

Table contents are too large to include in this report.

Table 6. The DirectSourceType domain table documenting fields and contents for 

direct source types.

[This data table contained five records as of August 1, 2014. This domain table serves the USADRS 

data table. *, primary key; CWS, community water system]

Field name Field

type Description

DirectSrceType_ID* Text Code identifying types of sources a CWS controls directly.

DirectSrceType Text Text description of source types.

Table contents:

DirectSrceType_ID DirectSrceType

C system includes both groundwater and surface-water sources

G system includes only groundwater sources

P system includes no sources (only purchased water)

S system includes only surface-water sources

U unknown (no information available about sources of water)
Structure and Data Sources for the Public-Supply Database 13

Table 7. The PurchaseSourceType domain table documenting fields and contents for purchase source types.

[This data table contained six records as of August 1, 2014. This domain serves the USADRS data table. *, primary key]

Field name Field

type Description

PurchaseSrceType_ID* Text Code identifying the sources of water purchased by community water systems.

PurchaseSrceType Text Text description of purchase water types.

Table contents:

PurchaseSrceType_ID PurchaseSrceType

C system purchases combined groundwater and surface water

G system purchases only groundwater

N system does not purchase water

S system purchases only surface water

U unknown (no purchase information available)

Y system purchases water (unknown type)

Table 8. The PurchaseStatus domain table documenting fields and contents for purchase information.

[This data table contained five records as of August 1, 2014. This domain serves the USADRS data table. *, primary key]

Field Name Field

Type Description

PurchaseStatus_ID* Text Code denoting types of sources a community water system uses through purchases 

from other suppliers.

PurchaseStatus Text Text description of source-water types.

Table contents:

PurchaseStatus_ID PurchaseStatus

B system only purchases water (does not sell)

I system is isolated (does not purchase or sell water)

S system only sells water (does not purchase)

T system both purchases and sells water

U purchase status is unknown

Table 9. The CustomerBase domain table documenting fields and contents for systems that supply water for 

domestic use.

[This data table contained three records as of August 1, 2014. This domain serves the USADRS data table. *, primary key]

Field Name Field

Type Description

CustomerBase_ID* Text Code that identifies systems whose customer base includes only domestic users. 

CustomerBase Text Text description of customer base.

Table contents:

CustomerBase_ID CustomerBase

A all

D domestic

U unknown
14 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

LatLonSource, LatLonDetMethod, and 

LatLonVerifyMethod Domain Tables

The three domain tables for locational information are 

LatLonSource (table 12), LatLonDetMethod (table 13), and 

LatLonVerifyMethod (table 14). These three domain tables 

document the sources and verification codes used for locational 

data in the USIN and USWL data tables. The PSDB includes 

locational information from the SDWIS, from other databases, 

and from other sources, including geocoded system mailing 

addresses, County and ZIP-code centroids, DeLorme Street Atlas 

USA (DeLorme, Inc., 2014), State agencies, and Web maps.

Summary

Protecting the quality of the Nation’s drinking-water 

supply has been a reponsibilty of the Federal government 

for decades. The U.S. Environmental Protection Agency 

(EPA) enforces Federal standards and requires State, local, 

and private water suppliers to implement the standards in 

their practices of water deliveries to the public. The EPA 

has developed the Safe Drinking Water Information System 

(SDWIS) for States to store information on public water 

systems. Although the SDWIS database is a comprehensive 

national database of public water systems and their facilities, 

the database has limitations. The U.S. Geological Survey 

(USGS) developed the Public-Supply Database (PSDB) to 

enhance the structure and content of information available 

from the SDWIS, adding value to the data to improve their 

usefulness for USGS studies.

The PSDB is a national dataset that includes information 

about wells, surface-water intakes, and distribution systems 

that are part of public water systems across the United States, 

its territories, and possessions. The purpose of this report is to 

document the PSDB and explain the methods used to populate 

and update the data from the SDWIS, State datasets, maps, 

and geospatial imagery. This report describes 3 data tables and 

11 domain tables, including field contents, data sources, and 

relations between tables. Although the PSDB database is not 

available to the general public, this report should be useful for 

others who are developing other database systems to store and 

analyze public water-supply system and facility data.

Table 10. The Availability domain table fields and contents documenting source availability.

[This data table contained seven records as of August 1, 2014. This domain serves the USIN and USWL data 

tables. *, primary key; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection 

Agency, 2014c)]

Field name Field

type Description

Availability_ID* Text Text code denoting SDWIS temporal availability (Availability).

Availability Text Text description of water availability.

Table contents:

Availability_ID Availability

E emergency

I interim (peak)

O other

P permanent

S seasonal

N no SDWIS value available

U unknown (no current match to SDWIS)
Summary 15

Table 11. The SiteType domain table documenting fields and contents for site types.

[This data table contained 24 records as of August 1, 2014. This domain serves the USIN and USWL data tables. *, primary key; 

NWIS, National Water Information System (Dupré and others, 2013); (null), not applicable]

Field name Field

type Description

SiteType_ID* Integer Integer code denoting type of water source.

SiteType Text Text description of source-water (site) type.

NWISType Text Corresponding site type used in NWIS after version 4.8.

NWISTypeOld Text Corresponding site type code used in older versions of NWIS (before version 4.8).

Table contents:

SiteType_ID SiteType NWISType NWISTypeOld

0 unknown (null) (null)

1 stream ST ST

2 lake LK LK

3 reservoir LK RS

4 infiltration gallery GW-CR RC

5 canal ST-CA CN

6 lock and dam ST ST

7 spring SP SP

8 great lakes LK LK

9 upstream end of reservoir ST ST

10 low-head dam (pool) LK RS

11 aqueduct ST-CA CN

12 off-stream reservoir LK SG

13 terminal reservoir canal ST-CA SG

14 mine or quarry SB-TSM MQ

15 water bank (conjunctive) (null) (null)

16 seawater OC-CO (null)

17 cistern FA-CI (null)

18 mine drain SB-TSM MQ

19 well under influence sw WL (null)

20 california aqueduct ST-CA CN

21 well GW W

22 wellfield GW-MW M
16 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Table 12. The LatLonSource domain table documenting location sources.

[This data table contained 54 records as of August 1, 2014. This domain serves the USIN and USWL data tables. *, primary key]

Field name Field

type Description

LatLonSource_ID* Text Text code denoting source of latitude/longitude value.

LatLonSourceDesc Text Description of location source.

Table contents:

LatLonSource_ID LatLonSourceDesc

AZ STATE State of Arizona

CDEC California Data Exchange Center (CDEC)

CT STATE DEP/USGS-NH Connecticut State DEP (modified by USGS-NH)

DE State State of Delaware

FL051 Hendry County, FL

IN STATE DEM/USGS-NH Indiana State Dept. of Environmental management

KS003 Anderson County, KS

MA STATE DEP Massachusetts Dept of Environmental Protection

MO STATE State of Missouri

NC STATE DWR North Carolina Dept of Water Resources

NC STATE DWR-NH North Carolina Dept of Water Resources (modified by USGS-NH)

NH STATE DES New Hampshire State Dept of Environmental Services

NH STATE DES-NH New Hampshire State Dept of Environmental Services (modified by USGS-NH)

OH STATE-NH State of Ohio (modified by USGS-NH)

SDWIS SDWIS/FED (date unknown)

SDWIS* SDWIS/FED (assumed - was blank)

SDWIS03 SDWIS/FED (2003 retrieval)

SDWIS05 SDWIS/FED (2005 retrieval)

SDWIS05-NH SDWIS/FED (2005 retrieval) (modified by USGS-NH)

SDWIS-CA SDWIS California

SDWIS-ID SDWIS Idaho

SDWIS-NH SDWIS New Hampshire

SDWIS-OLD SDWIS - older (original) retrieval

TX STATE State of Texas

TX STATE-NH State of Texas (modified by USGS-NH)

TX WDB Texas Water Development Board

USGS-CA USGS USGS-CA Water Science Center staff

USGS-CA-NH USGS USGS-CA Water Science Center staff (modified by USGS-NH)

USGS-CO USGS USGS-CO Water Science Center staff

USGS-CT USGS USGS-CT Water Science Center staff

USGS-GA USGS USGS-GA Water Science Center staff

USGS-IA-NH USGS USGS-IA-NH Water Science Center staff (modified by USGS-NH)

USGS-IN USGS USGS-IN Water Science Center staff

USGS-LA USGS USGS-LA Water Science Center staff

USGS-MA USGS USGS-MA Water Science Center staff

USGS-MA/RI USGS USGS-MA/RI Water Science Center staff

USGS-MI USGS USGS-MI Water Science Center staff

USGS-NH USGS USGS-NH Water Science Center staff

USGS-NJ USGS USGS-NJ Water Science Center staff

USGS-NJ-NH USGS USGS-NJ Water Science Center staff (modified by USGS-NH)

USGS-NV USGS USGS-NV Water Science Center staff

USGS-OK USGS USGS-OK Water Science Center staff

USGS-OR USGS USGS-OR Water Science Center staff

USGS-PA USGS USGS-PA Water Science Center staff

USGS-SD USGS USGS-SD Water Science Center staff

USGS-TN USGS USGS-TN Water Science Center staff

USGS-TX USGS USGS-TX Water Science Center staff

USGS-UT USGS USGS-UT Water Science Center staff

USGS-VA USGS USGS-VA Water Science Center staff

USGS-VOC USGS USGS-VOC Water Science Center staff

USGS-VT USGS USGS-VT Water Science Center staff

USGS-WA USGS USGS-WA Water Science Center staff

USGS-WV-NH USGS USGS-WV-NH Water Science Center staff (modified by USGS-NH)

VT STATE ANR-NH Vermont Agency of Natural Resources (modified by USGS-NH)
Summary 17

Table 13. The LatLonDetMethod domain table documenting location methods.

[This data table contained 48 records as of August 1, 2014. This domain serves the USIN and USWL data tables. *, primary key; EPA, U.S. Environmental 

Protection Agency; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection Agency, 2014c); PSDB, Public-Supply Database; NWIS, 

National Water Information System (Dupré and others, 2013); NAD83, North American Datum of 1983; NAD27; North American Datum of 1927; CWS, community water sytem; DeLorme Street Atlas USA, software product (DeLorme, Inc., 2014); GNIS, Geographic Names Information System (Yost and Carswell, 

2009)]

Field name Field

type Description

LatLonDetMethod_ID* Text Text code denoting method used to determine latitude/longitude value. These codes are based on EPA 

standard method codes used in the SDWIS (Environmental Data Standards Council, 2006) with additions specific to the PSDB.

LatLonDetMethod Text Text description of location method.

NWISMethod Text Corresponding NWIS coordinate method code.

EstDatum Text Horizontal datum to use for locations (as “best estimate”) if no other horizontal datum information is 

available.

Table contents:

LatLonDetMethod_ID LatLonDetMethod NWISMethod EstDatum

001 Address matching--house number U NAD83

006 Address matching--digitized U NAD83

007 Address matching--other: derived through the use of nonspecific matching techniques U NAD83

012 Global positioning system--carrier phase static relative positioning technique G NAD83

013 Global positioning system--carrier phase kinematic relative positioning technique G NAD83

014 Global positioning system-- (pseudo range) differentially corrected D NAD83

015 Global positioning system--(pseudo range) precise positioning service G NAD83

016 Global positioning system--(pseudo range) standard positioning service (selective 

availability off)

G NAD83

017 Global positioning system--(pseudo range) standard positioning service (selective 

availability on)

G NAD83

018 Interpolation--map M NAD27

019 Interpolation--photo M NAD27

020 Interpolation--to be defined M NAD27

021 Interpolation--other U NAD27

021OS Interpolated from other source owned by CWS U NAD27

022 Loran C positioning device L NAD83

023 Public land survey--quarter section M NAD27

024 Public land survey--section M NAD27

025 Classical surveying techniques S NAD83

026 Zip5 code--approximate centroid U NAD83

027 Unknown (no information available) U NAD83

027G Guess to County U NAD83

027NWIS Unknown method, data from NWIS U NAD83

027PS Unknown method, data from CWS U NAD27

028 Global positioning system--unspecified G NAD83

029 Global positioning system--(pseudo range) standard positioning service corrected using Canadian Active Control SystemG NAD83

030 Interpolation--digital map source N NAD83

030D Interpolation--DeLorme Street Atlas USA digital map source N NAD83

030DPS Interpolation--DeLorme Street Atlas USA digital map source and information from 

CWS

N NAD83

030GE Interpolation--Google Earth digital map source N NAD83

030GNIS Interpolation--GNIS digital map source N NAD83

030TS Interpolation--TerraServer digital aerial photo source N NAD83

030TZ Interpolation--Topozone digital map source N NAD83

034 Public land survey--eighth section N NAD83

035 Public land survey--sixteenth section N NAD83

038 ZIP+2 Code--centroid N NAD83
18 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Table 14. The LatLonVerifyMethod domain table documenting location verification methods.

[This data table contained 22 records as of August 1, 2014. This domain serves the USIN and USWL data tables. *, primary 

key; DeLorme, DeLorme Street Atlas USA, (DeLorme, Inc., 2014); EPA, U.S. Environmental Protection Agency; GNIS, 

Geographic Names Information System; SDWIS, Safe Drinking Water Information System (U.S. Environmental Protection 

Agency, 2014c); USGS, U.S. Geological Survey; NWIS, National Water Information System (Dupré and others, 2013); GIS, 

geographic information system; <, less than; >, greater than]

Field Name Field

Type Description

LatLonVerifyMethod_ID* Integer Integer code denoting method used to verify latitude/longitude value.

LatLonVerifyMethod Text Description of method used to evaluate locations.

Table contents:

LatLonVerifyMethod_ID LatLonVerifyMethod

0 none (not verified)

1 DeLorme and State/EPA data to 6 seconds

2 latitude/longitude based on source name and DeLorme

3 DeLorme

4 Web address and DeLorme

5 DeLorme and State/EPA data, not obviously wrong

6 State/EPA data, DeLorme and Web pages

7 DeLorme and State/EPA data, minor adjustment

8 DeLorme and owner location, not to specific source

9 DeLorme and owner location, to specific source

10 DeLorme and town location

11 GNIS and DeLorme

12 Web document and DeLorme

13 DeLorme and SDWIS location for other sources

14 DeLorme and State/EPA data OK, but no source name

15 DeLorme and State/EPA data, close

16 latitude/longitude within 5 seconds of NWIS

17 latitude/longitude plotted within County using GIS

18 latitude/longitude plotted outside County, checked as OK

19 latitude/longitude outside County by < 1 kilometer

20 latitude/longitude plotted outside County by > 1 kilometer

21 latitude/longitude from NWIS
References Cited 19

References Cited

Alexander, R.B., Smith, R.A., Focazio, M.J., and Horn, 

M.A., 1999, Source-area characteristics of large public 

surface-water supplies in the conterminous United 

States—An information resource for source-water assessment: U.S. Geological Survey Open-File Report 99‒248 

[cd-rom].

Alley, W.M., Evenson, E.J., Barber, N.L., Bruce, B.W., 

Dennehy, K.F., Freeman, M.C., Freeman, W.O., Fischer, 

J.M., Hughes, W.B., Kennen, J.G., Kiang, J.E., Maloney, 

K.O., Musgrove, MaryLynn, Ralston, Barbara, Tessler, 

Steven, and Verdin, J.P., 2013, Progress toward establishing a national assessment of water availability and use: 

U.S. Geological Survey Circular 1384, 34 p., accessed 

March 14, 2014, at http://pubs.usgs.gov/circ/1384.

DeLorme, Inc., 2014, DeLorme Street Atlas USA [software 

product information Web page]: accessed March 14, 2014, 

at http://delorme.com.

Dupré, D.H., Scott, J.C., Clark, M.L., Canova, M.G., and 

Stoker, Y.E., 2013, User’s manual for the National Water 

Information System of the U.S. Geological Survey—WaterQuality System, version 5.0: U.S. Geological Survey OpenFile Report 2013‒1054, 730 p., accessed March 14, 2014, at 

http://pubs.usgs.gov/of/2013/1054/. 

Environmental Data Standards Council, 2006, Latitude/Longitude Data Standard: Environmental Data Standards Council, 

Standard No. EX000017.2, January 6, 2006, 24 p., accessed 

March 14, 2014, at http://www.exchangenetwork.net/

standards/lat_long_standard_08_11_2006_final.pdf.

Focazio, M.J., Welch, A.H., Watkins, S.A., Helsel, D.R., and 

Horn, M.A., 1999, A retrospective analysis on the occurrence of arsenic in ground-water resources of the United 

States and limitations in drinking-water-supply characterizations: U.S. Geological Survey Water-Resources Investigations Report 99‒4279, 21 p., accessed March 14, 2014, at 

http://pubs.usgs.gov/wri/wri994279/. 

Gilliom, R.J., Hamilton, P.A., and Miller, T.L., 2001, The 

National Water-Quality Assessment Program—Entering a 

new decade of investigations: U.S. Geological Survey Fact 

Sheet 071‒01, accessed March 14, 2014, at http://pubs.usgs.

gov/fs/fs-071-01/.

Hutson, S.S., Barber, N.L., Kenny, J.F., Linsey, K.S., Lumia, 

D.S., and Maupin, M.A., 2004, Estimated use of water in 

the United States in 2000: U.S. Geological Survey Circular 

1268, 46 p., accessed March 14, 2014, at http://pubs.usgs.

gov/circ/2004/circ1268/.

Kenny, J.F., Barber, N.L., Hutson, S.S., Linsey, K.S., 

Lovelace, J.K., and Maupin, M.A., 2009, Estimated use of 

water in the United States in 2005: U.S. Geological Survey 

Circular 1344, 52 p., accessed March 14, 2014, at http://

pubs.usgs.gov/circ/1344/.

MacKichan, K.A., 1951, Estimated use of water in the United 

States—1950: U.S. Geological Survey Circular 115, 13 p., 

accessed March 14, 2014, at http://pubs.usgs.gov/circ/1951/

circ115/. 

MacKichan, K.A., 1957, Estimated use of water in the United 

States, 1955: U.S. Geological Survey Circular 398, 18 p., 

accessed March 14, 2014, at http://pubs.er.usgs.gov/

publication/cir398.

MacKichan, K.A., and Kammerer, J.C., 1961, Estimated use 

of water in the United States, 1960: U.S. Geological Survey 

Circular 456, 26 p., accessed March 14, 2014, at http://pubs.

er.usgs.gov/publication/cir456.

Murray, C.R., 1968, Estimated use of water in the United 

States, 1965: U.S. Geological Survey Circular 556, 53 p., 

accessed March 14, 2014, at http://pubs.er.usgs.gov/

publication/cir556.

Murray, C.R., and Reeves, E.B., 1972, Estimated use of water 

in the United States, 1970: U.S. Geological Survey Circular 

676, 37 p., accessed March 14, 2014, at http://pubs.er.usgs.

gov/publication/cir676.

Murray, C.R., and Reeves, E.B., 1977, Estimated use of 

water in the United States in 1975: U.S. Geological Survey 

Circular 765, 39 p., accessed March 14, 2014, at http://pubs.

er.usgs.gov/publication/cir765.

Seaber, P.R., Kapinos, F.P., and Knapp, G.L., 1994, Hydrologic unit maps: U.S. Geological Survey Water-Supply 

Paper 2294, 63 p., accessed March 14, 2014, at http://pubs.

usgs.gov/wsp/wsp2294/.

Solley, W.B., Chase, E.B., and Mann, W.B., IV, 1983, Estimated use of water in the United States in 1980: U.S. 

Geological Survey Circular 1001, 56 p., accessed March 14, 

2014, at http://pubs.er.usgs.gov/publication/cir1001.

Solley, W.B., Merk, C.F., and Pierce, R.R., 1988, Estimated 

use of water in the United States in 1985: U.S. Geological 

Survey Circular 1004, 82 p., accessed March 14, 2014, at 

http://pubs.er.usgs.gov/publication/cir1004.

Solley, W.B., Pierce, R.R., and Perlman, H.A., 1993, 

Estimated use of water in the United States in 1990: 

U.S. Geological Survey Circular 1081, 76 p., accessed 

March 14, 2014, at http://pubs.er.usgs.gov/publication/

cir1081.
20 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

Solley, W.B., Pierce, R.R., and Perlman, H.A., 1998, Estimated 

use of water in the United States in 1995: U.S. Geological 

Survey Circular 1200, 71 p., accessed March 14, 2014, at

http://pubs.er.usgs.gov/publication/cir1200.

U.S. Bureau of the Census, 2002, Federal Information 

Processing System (FIPS) Codes for States and Counties, 

revised May 6, 2002 [online document]: accessed March 

14, 2014, at http://www.census.gov/popest/data/counties/

totals/1990s/files/90s-fips.txt.

U.S. Bureau of the Census, 2014, American National 

Standards Institute (ANSI) Codes [online document]: 

accessed March 14, 2014, at http://www.census.gov/geo/

reference/ansi.html.

U.S. Environmental Protection Agency, 2014a, Laws & 

Statues—The Safe Drinking Water Act: accessed March 

14, 2014, at http://water.epa.gov/lawsregs/guidance/sdwa/

laws_statutes.cfm.

U.S. Environmental Protection Agency, 2014b, Public 

drinking water systems—Facts and figures: accessed 

March 14, 2014, at http://water.epa.gov/infrastructure/

drinkingwater/pws/factoids.cfm.

U.S Environmental Protection Agency, 2014c, Overview: 

Envirofacts—SDWIS: accessed March 14, 2014, at http://

www.epa.gov/enviro/facts/sdwis/.

U.S. Government Printing Office, 2012, Part 141.2, 

Definitions—National Primary Drinking Water Regulation, 

in Electronic Code of Federal Regulations: accessed March 

14, 2014, at http://www.gpo.gov/fdsys/pkg/CFR-2012-

title40-vol24/pdf/CFR-2012-title40-vol24-sec141-2.pdf.

U.S. Geological Survey and U.S. Department of Agriculture, 

Natural Resources Conservation Service, 2013, Federal 

standards and procedures for the National Watershed 

Boundary Dataset (WBD), Techniques and Methods 11‒A3, 

63 p., accessed March 14, 2014, at http://pubs.usgs.gov/

tm/11/a3/.

U.S. Geological Survey, 2014a, National Water Census: 

accessed March 14, 2014, at http://water.usgs.gov/

watercensus/.

U.S. Geological Survey, 2014b, Water use in the United 

States: accessed March 14, 2014, at http://water.usgs.gov/

watuse/.

U.S. Geological Survey, 2014c, Water use terminology: 

accessed March 14, 2014, at http://water.usgs.gov/watuse/

wuglossary.html.

Yost, A.Y., and Carswell, W.J., Jr., 2009, Geographic 

names: U.S. Geological Survey Fact Sheet 2009–3016, 

2 p., accessed March 14, 2014, at http://pubs.usgs.gov/

fs/2009/3016/.
Glossary 21

Glossary

active A public water system that is 

recorded in the Safe Drinking Water Information System (SDWIS) database as operating; only active systems and facility records 

have been included in SDWIS data retrievals 

used to populate the Public-Supply Database 

(PSDB). This terminology is used in this 

report specifically for the classification within 

the SDWIS, as it is clear that some of these 

“active” facilities are no longer in use (for 

example, the facility is named “WELL 01–

DESTROYED”). See inactive.

commercial water use Water that is used 

for motels, hotels, restaurants, office buildings, other commercial facilities, and military 

and nonmilitary institutions (U.S. Geological 

Survey, 2014c).

community water system A public water 

system that serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents 

(U.S. Environmental Protection Agency, 

2014b).

data table A database table whose rows 

contain data. Some field values in the table 

may be limited to a list of values. See domain 

table.

domain table A database table whose 

field values are used to define unique values 

(“keys”) that are the only values allowed in 

particular data table field. Other information 

associated with each key may be included 

in the domain table; for example, if the key 

value represents a State code, fields containing State name and information about each 

State also may be included in the domain 

table. Domain tables can be used for database 

quality control and in the building of queries 

that join selected rows with other tables in the 

database.

domestic water use Water used for indoor 

household purposes such as drinking, 

food preparation, bathing, washing clothes 

and dishes, flushing toilets, and outdoor 

purposes such as watering lawns and gardens 

(U.S. Geological Survey, 2014c).

distribution system A network of storage 

tanks, valves, pumps, pipes or other 

constructed conveyances that transport 

finished water from a treatment plant, or 

wherever the water is diverted or pumped 

from, to consumers (U.S. Government Printing Office, 2012).

facility A groundwater source or surfacewater source used to collect water to be 

distributed by a public water system. See

groundwater source, surface-water source, 

and public water system.

Federal Information Processing Standard 

(FIPS) FIPS codes uniquely identify 

geographical areas in the United States and 

its territories and possessions. FIPS codes are 

maintained by the National Institute of Standards and Technology, and used extensively 

by Federal agencies. The U.S. Census Bureau 

uses FIPS codes to identify legal and statistical entities for geographical tabulations of 

population, demographic, and economic data 

(U.S. Bureau of the Census, 2002, 2014). 

foreign key A database table field that is 

used to join rows between two tables. The 

values of this field need not be unique in the 

source table but must be unique in the destination table (forming a “one-to-many join”).

groundwater Water that public water 

systems pump and treat from groundwater 

sources. 

groundwater source A groundwater 

source is a source of water that is taken from 

beneath the earth’s surface. Most public water 

systems with groundwater sources pump and 

treat groundwater from wells drilled into 

the ground to capture water flowing below 

surface level. Although other types of sources 

may be used (such as well fields, springs, and 

cisterns), in the context of this report, groundwater sources are referred to in this report as 

wells.

inactive A facility or public water system in 

the Safe Drinking Water Information System 

(SDWIS) database that is recorded as not in 

operation. See active.
22 Documentation for the U.S. Geological Survey Public-Supply Database in the United States

industrial water use Water used for fabrication, processing, washing, and cooling 

(U.S. Geological Survey, 2014c).

intake See surface-water source.

non-transient non-community water 

system A public water system that supplies 

water to 25 or more of the same persons at 

least 6 months per year in places other than 

their residences. Some examples are schools, 

factories, office buildings, and hospitals that 

have their own water systems (U.S. Environmental Protection Agency, 2014b).

primary key A database table field with 

a unique value. This field can be used to 

uniquely identify each table row.

population served The estimated number of 

individuals that are served by the public water 

system or the aggregated estimated number 

of individuals that are served by a group of 

public water systems.

public water system (PWS) A system of 

pipes or other constructed conveyances 

capable of providing water for human 

consumption to at least 15 service connections, or regularly serves at least 25 individuals, for at least 60 days per year. Public water 

systems are subject to the National Primary 

Drinking Water Regulations under the Safe 

Drinking Water Act. A public water system 

is either a community water system or a noncommunity water system (U.S. Government 

Printing Office, 2012).

Public Water System Identification 

(PwsID) A number that identifies a specific 

public water system. PwsID numbers are 

composed of alphanumeric characters and are 

created by the U.S. Environmental Protection Agency Information Collection Rule 

Water Utility Database System. The PwsID is 

used in the Safe Drinking Water Information 

System (SDWIS) and Public-Supply Database 

(PSDB) to link facilities with public water 

systems.

Safe Drinking Water Information System 

(SDWIS) The SDWIS is used by the 

U.S. Environmental Protection Agency to 

collect and manage drinking-water system 

inventory and compliance data submitted by 

the States and Tribes. Data are collected by 

the States and other agencies using SDWIS; 

these data are then compiled into a nationwide aggregated database known as “SDWIS/

Federal” or “SDWIS/FED.” In the context of 

this report, the term “SDWIS” is used to refer 

to this aggregated National database.

source-water type Type of water collected 

at a facility or used in a public water system. 

Examples of source-water types include 

stream, lake, reservoir, spring, or well.

surface water Water that public water 

systems pump and treat from sources open 

to the atmosphere, such as rivers, lakes, and 

reservoirs (U.S. Government Printing Office, 

2012).

surface-water source A source of water 

that is open to the atmosphere and subject to 

surface runoff. Examples of surface-water 

sources include lakes, rivers, reservoirs, and 

infiltration galleries. For simplicity, in the 

context of this report, a surface-water source 

is referred to as an intake.

transient non-community water system A 

non-community water system that does not 

regularly serve at least 25 of the same persons 

over six months per year (U.S. Government Printing Office, 2012). These systems 

do not have to test or treat their water for 

contaminants that pose long-term health risks, 

because fewer than 25 people drink the water 

over a long period of time. They still must test 

the water for microbes and several chemicals.

water use In a restrictive sense, the term 

refers to water that is withdrawn for a 

specific purpose, such as for public supply, 

domestic use, commercial, industrial, or 

other types of uses. A broader definition 

of water use includes the interaction of 

humans with and influence on the hydrologic 

cycle, and includes elements such as water 

withdrawal delivery, consumptive use, and 

wastewater returns to the hydrologic system 

(U.S. Geological Survey, 2014c).

well See groundwater source.

withdrawal Water removed from the ground 

or diverted from a surface-water source for 

use (U.S. Geological Survey, 2014c).
Glossary 23

Publishing support provided by: 

Rolla Publishing Service Center

For more information concerning this publication, contact:

Director, USGS South Dakota Water Science Center

1608 Mountain View Road

Rapid City, South Dakota 57702

(605) 394–3200

Or visit the South Dakota Water Science Center Web site at: 

http://sd.water.usgs.gov/
Price and Maupin—Documentation for the U.S. Geological Survey Public-Supply Database in the United States—OFR 2014–1212

ISSN 2331-1258 (online)

http://dx.doi.org/10.3133/ofr20141212