Storage and Retrieval of 

Ground-Water Data at the 

U.S. Geological Survey 

GEOLOGICAL SURVEY CIRCULAR 856 

Yes 

Yes 

Storage and Retrieval of 

Ground-Water Data at the 

U.S. Geological Survey 

By Maria W. Mercer and Charles 0. Morgan 

GEOLOGICAL SURVEY CIRCULAR 856 

1982 
United States Department of the Interior 

JAMES G. WATT, Secretary 

Geological Survey 

Dallas L. Peck, Director 

Library of Congress catalog-card No. 82-600558 

Free on application to Distribution Branch, Text Products Section, 

U.S. Geological Survey, 604 South Pickett Street, Alexandria, VA 22304 
CONTENTS 

Page 

)lbstract-------------------------------------------------------------------------------

lntroduction----------------------------------------------------------------------------

Purpose -------------------------------------------------------------------------------

History of the G WSI--------------------------------------------------------------------- 1 

Structure of GWSI ---------------------------------------------------------------------- 2 

Collection of data for GWSI -------------------------------------------------------------- 2 

Quality control and entry of GWSI data ---------------------------------------------------- 4 

Retrieval of data from GWSI-------------------------------------------------------------- 6 

Users and use of the GWSI---------------------------------------------------------------- 6 

Conclusions---------------------------------------------------------------------------- 9 

Referencescited------------------------------------------------------------------------- 9 

ILLUSTRATIONS 

Page 

Figure 1. Chart showing the hierarchical structure of GWSI data base--------------------------- 2 

2. Graph showing increase in the number of sites in the GWSI data base ------------------- 5 

3. Map showing the number of GWSI sites per State and Puerto Rico --------------------- 5 

4. Water-level table produced by using a natural language retrieval 

command, which is listed above the table ------------------------------------------- 6 

5. Report table of GWSI data produced by PLEX program------------------------------ 7 

6. Hydrograph showing water levels in a typical well during a 20-year 

period of record ---------------------------------------------------------------- 7 

7. Computerized map plot from GWSI data base on 

a Kansas county outline --------------------------------------------------------- 8 

TABLES 

Page 

Table 1. Description of GWSI schema records----------------------------------------------- 3 

2. Location of N)l WDEX )lssistance Centers------------------------------------------ 9 

III 

Storage and Retrieval of Ground-Water Data 

at the U.S. Geological Survey 

By Maria W. Mercer and Charles 0. Morgan 

ABSTRACT 

The U.S. Geological Survey maintains a computerized GroundWater Site-Inventory (GWSI) file that contains information about 

wells and springs at sites from all States of the United States. This 

file contains data collected by U.S. Geological Survey personnel 

and personnel of cooperating State, local, and Federal agencies. 

The file is easily accessible to members or users of the National 

Water Data Exchange (NA WDEX). Since the establishment of the 

GWSI file in 1974, the data base has grown 19 percent per year and 

contains information on about 770,000 sites as of February 1981. 

INTRODUCTION 

In the mid-1960's, ever-increasing amounts of data 

and a need for timely access to these data necessitated 

computerized data banks for the storage of information such as personnel records, daily business and financial records, and, in the case of the U.S. Geological Survey, hydrologic records. In keeping with one 

of the Survey's missions, that of collecting and publishing information about the Nation's natural resources (U.S. Geological Survey, 1981), the Survey 

created and maintains a central storage facility for 

water resources data known as the National Water 

Data Storage and Retrieval System (W A TSTORE), 

at its National Headquarters in Reston, Va. Included 

in this computerized storage facility are representative ground-water data collected throughout the 

United States·. This ground-water information resides 

in an online computer data file, which is maintained 

by a Data Base Management System (DBMS) called 

SYSTEM 20001 (MRI Systems Corp., 1974a). The 

name and acronym given this data base is the 

Ground- Water Site-Inventory (GWSI) file. 

'The use of brand or company names in this report is for identification 

purposes and does not constitute endorsement by the U.S. Geological 

Survey. 

1 

PURPOSE 

As demand for ground water increases, the availability of site-specific ground-water data becomes 

very important in solving such problems as those involving water-supply and waste-disposal operations. 

To make competent management decisions concerning these problems, all available ground-water data 

in the vicinity of a site should be scrutinized as part 

of the evaluation process. This paper describes the 

various ground-water data elements that reside in the 

GWSI and explains how these data are entered and 

retrieved. 

HISTORY OF THE GWSI 

Twenty years ago, ground-water data collected in 

field offices by Survey hydrologists were stored in filing cabinets, many times on locally devised nonstandard inventory forms. During the 1960's, an attempt 

was made within the Survey to establish a standard 

approach to the storage of ground-water data in anational computer file (Lang and Leonard, 1967). Because of the specialized needs of hydrologists in 

diverse climatic and geologic areas of the country and 

the limitations of the data system, the national computer file was not used widely. 

Because of the increasing demand for timely 

ground-water data, a need arose to redesign the 

structure of the data system to satisfy more fully the 

requirements of hydrologists and to establish a centrally controlled computer file that could be easily accessed by all users. A decision was reached in the 

early 1970's to obtain a commercially developed 

computerized DBMS to organize and maintain this 

file of raw ground-water data. The GWSI was designed and implemented in 1974, as documented in 

the "WATSTORE User's Guide, Volume 2" (U.S. 

Geological Survey, 1975), using the newly acquired 
DBMS, SYSTEM 2000. The chief purposes of the 

GWSI are (1) to meet the need for storage of nationally standardized ground-water data and (2) to 

provide nationwide computer access to these data. 

Because nationwide ground-water data are stored 

in one easily accessible computer file, the GWSI is a 

very useful tool for interpreting the hydrogeology of 

an area. An organization using the GWSI to work on 

projects throughout the Nation needs to learn only 

one retrieval technique to obtain the output in a standard format; this allows more time for the analysis of 

the findings. The tedious computer programing required for adjusting to different data sources is 

eliminated by using the standardized G WSI data 

base. 

STRUCTURE OF GWSI 

The structure of a SYSTEM 2000 data base is 

hierarchical, sometimes called a tree structure (see 

fig. 1). The top node (box) of this treelike structure 

is, in fact, the root, and, if turned upside down, the 

structure resembles a tree with its limbs branching upward. The top node, called ENTRY, which contains 

a unique identification number and location information for a ground-water site, can have many descendants (branches downward). However, no descendants may have more than one parent (branches 

upward). Figure 1 illustrates these relations. ENli:2 

! 

z: 

I 

I l I 

TRY, the top node, has descendants, including 

LIFT, CONSTRUCTION, and GEOLOGY data. 

However, LIFT has only one parent, ENTRY. 

Each of these nodes, called schema records, contains 

up to 46 components of site information leading to 

270 possible data items per site. Not all 270 possible 

data items are coded for any one site. Some items are 

unique to specific site types; for example, springs. If 

a ground-water site contains only the data listed in 

the top node (ENTRY (location data)) then only 

these data are in the file. The other schema records 

are not established until pertinent data are entered into the GWSI and, thus, do not occupy valuable computer disk file space. The SYSTEM 2000 DBMS uses 

indexing techniques to keep track of the locations of 

data items that are stored randomly in an online computer disk file. This indexing feature simplifies the 

addition of data to the GWSI file and makes retrievals more efficient. 

COLLECTION OF DATA FOR GWSI 

The bulk of the data in the GWSI file is collected 

by Survey personnel as part of water-resources investigations and water-level monitoring programs, 

in cooperation with State and local governments and 

other Federal agencies. Typically, data are collected 

by a hydrologist who inventories wells or springs by 

I I I I l I I I 

FIGURE I.-Hierarchical structure of GWSI data base. 

2 
examining them in the field. The information obtained 

is transcribed onto standard forms designed for the 

recording of data for input to the computer file. 

Most data in the GWSI file are raw ground-water 

data entered by the inputting agency. Few statistical 

items are stored because these values can be readily 

calculated from raw data residing in the data base. 

Some of the categories of data that can be stored in 

schema records for each site in the GWSI are listed in 

table 1. Table 1 describes the schema records in 

figure 1 starting with the top node ENTRY, proceeding down each branch, then left to right. 

TABLE !.-Description ofGWSI schema records 

[For a detailed explanation of all components within each schema record available in the GWSI see "WATSTORE User's Guide, Volume 2," 

Chapter II, Section B ] 

Schema record Description of information 

ENTRY ----------------------------------Site identifiers such as latitude and longitude, altitude, State, county, and so forth. 

LIFT-----------------------------------Type, such as pump or bucket; includes horsepower, intake setting, and so forth. 

MAJOR PUMP------------------------Manufacturer, serial number, energy consumption, capacity, and so forth. 

STANDBY ----------------------------Alternative power types. 

CONSTRUCTION 

CONSTRUCTION ---------------------Date of completion, contractor, seal type, finish, and seal bottom. 

HOLES-----------------------------Type of well and dimensions, including diameter of top and bottom of hole. 

OPENINGS-------------------------Depth intervals of perforated zones, size and shape, and screen material. 

CASINGS --------------------------Type and material, top in reference to land surface, depth to bottom, and diameter of 

each string. 

MINOR REPAIRS---------------------Repair information. 

GEOLOGY 

GEOHYDROLOGIC UNITS ------------Name of formation, including unit identifier and its depth. 

AQUIFERS -------------------------Includes static water level in aquifer. 

HYDRAULIC---------------------------Includes the unit identifier. 

COEFFICIENTS ----------------------Includes conductivity, diffusivity, and leakance. 

NETWORKS 

QUALITY NETWORK-----------------Water-quality network, including name of agency that gathers samples at site. 

LEVEL NETWORK--------------------Water-level network, including name of agency that collects water-level measurements 

at site. 

PUMP AGE NETWORK----------------Pumpage network, including name of agency that monitors water withdrawal at site. 

PRODUCTION 

FLOW DATA -------------------------Information about springs, including flow period and discharge. 

PUMP PRODUCTION -----------------Production of the well, including production date and method. 

OWNERS-------------------------------The site's owner, name, and ownership date. 

SPRINGS-------------------------------Spring data; for example, name and number of openings. 

ADDITIONAL INFORMATION 

REMARKS ---------------------------Additional remarks about the site. 

MISCELLANEOUS DATA ---------------Other references and sources of data. 

SITE VISITS --------------------------Visits to the site, such as the inventory person and date of visit. 

OTHER DATA------------------------Location and formats of other data available about the site. 

OTHER IDENTIFICATION ------------Other site identifiers. 

3 
TABLE !.-Description ofGWS/ schema records-Continued 

Schema record 

ENTRY -Continued 

WATER QUALITY 

Description of information 

FIELD WATER QUALITY1-------------Field water-quality data, such as the sample date, the constituent, its measurement, and 

source (aquifer name). 

LOG 

LOGS --------------------------------Type of geophysical or other logs available for the well, including type and source. 

SPECIAL CASES 

WELL GROUP------------------------Multiple wells that are manifolded to a single discharge pipe, including the number of 

wells and the deepest and shallowest wells in the group. 

POND, TUNNEL, DRAIN--------------The length, width, and depth of a pond, tunnel, or drain. 

COOPERATOR DATA-----------------Data that cooperating local agencies need, such as cooperator's site identifier, registration number, and so forth. 

LATERALS---------------------------Information about Ranney wells, including the depth, length, and diameter of the 

laterals that drain to the central well. 

MISCELLANEOUS VALUES -----------Data for which no other schema record has been established. 

STATE WATER USE ------------------The State's use of water, including water type and the amount of water. 

OBSERVATION WELLS 

HEADING----------------------------Textual information about the site. 

YEAR --------------------------------Specific year for data in the lower level schema record(s). 

WATER LEVELS--------------------Includes water-level measurements and respective dates. 

MEASURING POINT ------------------Includes the measuring point height and the date when the measurement was made. 

1 Although several field collected parameters of water-quality data (including temperature, conductance, and pH) are stored in the GWSI, the bulk of waterquality data reside in a nationwide file called Storage and Retrieval (STORET), a file maintained by the U.S. Environmental Protection Agency (1973). The 

National Water Data Exchange (NA WDEX) Local Assistance Centers provided in table 2 are authorized users of the STORET file and may retrieve groundwater-quality data for its subscribers. 

QUALITY CONTROL AND ENTRY OF 

GWSI DATA 

All ground-water data input to the GWSI data 

base should be reviewed for accuracy. The primary 

quality control measures are the responsibility of the 

inputting office. Once that office is satisfied that the 

data on field forms are correct, these data are transcribed to the format required for entry into the computer; for example, punched cards. Before entry into 

the GWSI file, the data are checked for logic and syntax errors by the inputting office by using a computerized verification system. This series of computer 

programs provides several types of error checks, such 

as (1) syntax check, which ensures valid input data 

(for example, correct codes are used and alphabetic 

characters are not entered where numeric data belong); (2) compatibility check, which ensures compatibility between data elements that are being 

entered or between input values and those that 

already reside in the data base (the depth to water, 

for example, cannot exceed the depth of the well); 

and (3) out-of-range check, which indicates whether 

input data fall within the bounds of certain parameters provided in tables in the computer programs 

4 

(for example, maximum and m1mmum values of 

latitude, longitude, and altitude reside in the tables 

for each State). 

Input data will be entered into the GWSI file by the 

GWSI Data Base Manager (DBM) at the Survey's 

National Headquarters when all data have passed the 

error checks. All reports concerning final verification 

of the update process to the GWSI are sent to the 

originating office. 

The inputting office may not directly update the 

GWSI data base. Only the DBM may update. Once 

the data are in the GWSI file, the inputting office 

must verify these data and correct any errors, such as 

transposition of numbers or misspelling of names 

that were not detected earlier in the proofing process. 

Erroneous data can be modified easily by the inputting office. 

Non-Survey organizations that wish to enter data 

into GWSI must establish access to the data base by 

registering with the NA WDEX Program Manager. 

Detailed information about accessing the GWSI is 

discussed in a subsequent section entitled "Users and 

Use of the GWSI." Non-Survey organizations may 

obtain standard forms for encoding input informa-
tion in the GWSI format by contacting GWSI personnel of the Survey at the National Headquarters. 

Since the inception of the GWSI file, the data base 

has grown at an average of 19 percent per year and 

contains information related to about 770,000 sites, 

800 

""" Q 

:z: 

:'i 

5 

i5 

a!: 700 

"' ~ 

~ 

t:=; 

311:: 

~ 

.... 600 0 

a.: 

..... 

CD 

2: 

:z: = 

soo 

1978 1979 

as of February 1981. Figure 2 indicates the growth 

pattern for the past 3 years. The number of groundwater sites for which data have been entered into the 

GWSI file for each State, including Puerto Rico, is 

shown in figure 3. 

769,451 

(2/15/81) 

1980 1981 

FIGURE 2.-Increase in the number of sites in the GWSI data base. 

ALASKA 

13,158 

43,749 

PUERTO RICO 

~1680 0 80 MILES 

0 

~ 

80 KILOMETERS 

\l\\q ~\\\\) 

\~~Ab~~~) 

t> \11Mlt\) 

l111~0) 

56110U1 

l~Ui) 

0 400 MILES 

I I II II I I I 

0 400 KILOMETERS 

FIGURE 3.-Number of GWSI sites per State and Puerto Rico. 

5 
RETRIEVAL OF DATA FROM GWSI 

Once data reside in the GWSI, their retrieval is 

relatively simple. This capacity for quick, efficient 

retrieval is the primary purpose for choosing a 

DBMS for storage of ground-water data. The SYSTEM 

2000 DBMS "Natural Language" (MRI Systems 

Corp., 1974b) computer program allows persons not 

trained in computer languages to use brief, Englishlike commands to retrieve simple printouts of data. A 

water-level table produced by using this program is 

shown in figure 4. For more elaborate presentation 

of data, a feature called "Report Writer" (MRI 

Systems Corp., 1974c) is available as part of the 

DBMS. 

If the "Natural Language" and "Report Writer" 

facilities are insufficient for retrieving data in a 

prescribed format, SYSTEM 2000 has an additional 

feature, "Programing Language Extension" (PLEX) 

(MRI Systems Corp., 1979) that can include 

prescribed SYSTEM 2000 statements in the code of a 

higher level programing language, such as COBOL, 

LIST/REPEAT SUPPRESS/ C1 ,C235,C237 

WH C1 EO 392854106024501 OR 

C1 EO 393439106055901 OR 

C1 EO 393633105580601: 

FORTRAN, and PL/1. With PLEX, any GWSI data 

item can be manipulated at the user's discretion. The 

user may produce specialized reports, use statistical 

or graphical routines, and pass data to or merge with 

other computer files. The Survey has several PLEX 

computer programs that produce report tables, X-Y 

plots, and map plots for many of the data in the 

GWSI (see figures 5, 6, and 7). 

USERS AND USE OF THE GWSI 

The principal contributors to, and users of, the 

GWSI are personnel of the Survey. However, many 

engineering and environmental consultants retrieve 

data from the GWSI file, as do university researchers 

and State and local governmental agencies. Individuals also request ground-water information for their 

own use. 

An evaluation of the ground-water resources of an 

area generally begins with a perusal of the existing 

data. For many areas, GWSI provides this starting 

point by supplying information about many of the 

* SITE-10 WL-MEAS-DATE WL-MEASUREMENT 

*** 

* 392854106024501 08/10/1976 19.73 

* 09/13/1973 21.00 

* 09/17/1975 20.31 

* 10/14/1974 25.44 

* 393439106055901 08/09/1977 18.91 

* 08/10/1976 12.40 

* 09/14/1973 11.88 

* 09/17/1975 11.96 

* 08/09/1978 13.23 

* 08/22/1979 11.89 

* 393633105580601 08/10/1976 40.66 

* 09/23/1977 42.27 

* 09/13/1973 43.41 

* 09/17/1975 41.89 

* 10/14/1974 43.90 

* 08/09/1978 41.62 

* 08/22/1979 43.39 

* 08/07/1980 43.58 

FIGURE 4.-Water-level table produced by using a "Natural Language" retrieval command, which is listed above the table. 

6 
ALTITUDE 

OF LAND USE 

SURFACE OF 

LOCAL NUMBER (FEET) SITE 

SC01604632DDAC1 0 75 w 

SC01604634BCBC 1 0 50 w 

SC01604634BCDD1 0 55 w 

SC01604634BCDD2 0 55 w 

SC01604634CBAD1 0 35 w 

SC01704429CBDC1 0 90 u 

SC01704510DCCC1 0 60 w 

SC01704514BDDD1 0 80 w 

SC01704522BBBC1 0 50 w 

SC01704522CCAB 1 0 25 w 

SC01704523ABAC 1 0 75 w 

SC01704523ACCB 1 0 50 u 

SC01704523ADCC1 0 75 z 

SC01704523BACD1 0 75 w 

SC01704523BACD2 0 75 w 

SC01704523BBAB1 0 75 w 

SC01704523CDCB 1 0 35 u 

SC01704523CDCB2 0 35 w 

SC01704523CDCB3 0 35 w 

SC01704523CDCD1 0 35 w 

( 1) Use of Water 

W Withdrawal of Water 

U Unused 

Z Destroyed 

USE 

OF 

WATER OWNER 

H HAZENBERG, HANK 

H ERICKSON, ARNE 

H COOK, TIM 

H BLUSH, ROBERT 

H HILL, FRANK 

u USAF KGSLM, 3RD RADIO 

H ANGASAN, RALPH 

c RCA WH ALC, KING SLM 

H WILLIAMS, BERTHA 

p FAA, KING SLM 

USAF, KING SLM 

u USAF, KING SLM 

u USAF, KING SLM 

p USAF, KING SLM 

p USAF, KING SLMN 

p USAF, KING SLM 

u WOOD Z, LODGE 

c WOOD Z, LODGE 

c EDDIES, FRPLC IN 

z ADF & G, KING SLM 

Explanation of codes: 

(2) Use of Water 

H Domestic 

U Unused 

C Commercial 

P Public Supply 

Z Other 

PRINCIPAL TEMPERATURE 

AQUIFER (DEGREES C) 

1100RNR 

110QRNR 

1100RNR 

1100RNR 3.0 

1100RNR 

1100RNR 

1100RNR 

110QRNR 

110QRNR 5.0 

1100RNR 

1100RNR 

1100RNR 

1100RNR 5.0 

1100RNR 

1100RNR 

(3) Principal Aquifer 

Quaternary System 

SPECIFIC 

CONDUCTANCE 

(UMHOS/CM 

AT 25 C) 

70 

1100 

280 

FIGURE 5.-Report table of GWSI data produced by PLEX program. 

w 

(.) 

<( 

LL 

a: 

:::> 

8 

en 10 

c 

z 12 <( 

...J 

~ 22 

:i 1- 24 Q. 

~ 26~--4---~--~--~--~---L---L--~--~--~--~~--~--._--~--~--~---L--~--~---J 

1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 

BN-24/20E/18-0013 MONTHLY LOW WATER LEVEL 

FIGURE 6.-Hydrograph showing water levels in a typical well during a 20-year period of record. Dashed line indicates period of 

intermittent record. 

7 
r-------..,..__. ------------r----

I • o.~3 • -1.89 • • -0.36 o.93 ---------------l 

I •-3.44 I 

I • • I 

I ·-0.52 ·-0.47 •-1.79 • 0.99 I ·-3.00 

/

1 •• -3 .• 75 • 2.61 ! -6.40. 

• • -5.91 -1.87. 

I •-5.67 • • I 

I 

•-1.40 • • -5.08 I 

• -5.25 

/

1 • -3.53. • -7.06 • • I •-3.51 

·-0.05 ·-2.87 • -1.22 0.94. • -0.!.9 •-26.50 • _ 0_

53 I 

I • •-9.35 I 

I . -0.97 • -2. 10 • -3.51 • • 0.00 -5.43 • 

• -2.39 • -0.66 .-3.90 r----_____ 2.00 -092 I .-8.oo ... -----... -· ----_ ----J 

I -5.49: •-6.16 • -1.48 -1.99• 

I •• • •-7.16 I • .. -5.41 I • • • •-4.55 .-2.45 I ••• • .-2.54 

•-3.83 :• -3,80 •-2.06 -2.42• •-1.35 • -0.75 I 

I -7.22• •o.66 I ·-3.96 •11.31 1 -3.98• ._3_

63 • 1.98 

I 

• -0.05 II • -2.44• .-1.98. -1.34 

Ll •-4· 29 -3.42. ·-2.78 •-2.75 • I .-3.07 • -3.21 I 

I • -3.51 -2. 10f 

1 .-2.69 I 1 • -7.92 • •-7.06 

L____ I ---------- -2.82• _ 599 -3.2_7 1 --- --...a.:~--- !...1 

0 5 10 MILES 

I I I I I 0 5 10 KILOMETERS 

FIGURE 7 .-Example of computerized map plot from the GWSI data base, on a Kansas county outline. Water level changes, in feet, 

are indicated at many sites. 

existing wells and springs. Historical water-level 

data, from which hydrographs and maps of potentiometric surfaces may be constructed, are particularly 

helpful. These data also may aid in interpreting the 

effects of climate fluctuations and resource development in the area under study. 

Data may be obtained from the GWSI either by 

submitting a request to NA WDEX (Edwards, 1978) 

or by establishing direct, online access to the data 

bases. NA WDEX services are available through a nationwide network of Assistance Centers (Edwards, 

1980) located in 45 States and Puerto Rico. The locations of these centers are given in table 2, and a free 

directory of all Assistance Centers may be obtained 

8 

from NA WDEX (see the address given below). 

Charges for retrieving data are assessed at the rate of 

the actual cost of retrieval of the requested data 

from the GWSI. Those users desiring direct, online 

access to the GWSI must sign a Memorandum of 

Agreement with the Survey for this purpose and must 

assume full financial responsibility for their use of 

the Survey's computer system. This agreement 

authorizes users to input data to the GWSI, as well as 

make retrievals from it. Requests for direct access to 

the data base must be submitted in writing to the Program Manager, National Water Data Exchange, U.S. 

Geological Survey, 421 National Center, Reston, VA 

22092. 
TABLE 2.-Locations of NA WDEX Assistance Centers 

ALABAMA----------------Tuscaloosa. 

ALASKA ------------------Anchorage. 

ARIZONA-----------------Tucson. 

ARKANSAS Little Rock. 

CALIFORNIA -------------Menlo Park. 

COLORADO---------------Lakewood (Denver) and 

Ft. Collins. 

CONNECTICUT -----------Hartford. 

FLORIDA -----------------Tallahassee, Miami, Orlando, and 

Tampa. 

GEORGIA -----------------Doraville (Atlanta). 

HAW All ------------------Honolulu (also serves American 

Samoa and Guam). 

IDAHO -------------------Boise. 

ILLINOIS -----------------Champaign. 

IND lANA -----------------Indianapolis. 

IOWA---------------------Iowa City (2 locations). 

KANSAS ------------------Lawrence. 

KENTUCKY ---------------Louisville. 

LOUISIANA---------------Baton Rouge. 

MARYLAND --------------Towson (also serves Delaware 

and District of Columbia). 

MASSACHUSETTS --------Boston (also serves Maine, New 

Hampshire, Rhode Island, 

and Vermont). 

MICHIGAN ---------------Okemos (Lansing) and 

Ann Arbor. 

MINNESOTA --------------St. Paul. 

MISSISSIPPI --------------Jackson. 

MISSOURI ----------------Rolla. 

MONT ANA----------------Helena. 

NEBRASKA ---------------Lincoln (2 locations). 

NEVADA------------------Carson City. 

NEW JERSEY--------------Trenton. 

NEW MEXICO-------------Albuquerque. 

NEW YORK ---------------Albany and Syosset. 

NORTH CAROLINA -------Raleigh. 

NORTH DAKOTA----------Bismarck. 

0 HI 0 ---------------------Columbus. 

OKLAHOMA --------------Oklahoma City. 

OREGON------------------Portland and Salem. 

PENNSYLVANIA ----------Harrisburg and Philadelphia. 

PUERTO RICO ------------Ft. Buchanan (San Juan) (also 

serves Virgin Islands). 

SOUTH CAROLINA--------Columbia. 

SOUTH DAKOTA ----------Huron. 

TENNESSEE---------------Nashville. 

TEXAS--------------------Austin. 

UTAH --------------------Salt Lake City (2 locations) and 

Logan. 

VIRGINIA-----------------Richmond, Blacksburg, and 

Reston. 

WASHINGTON------------Tacoma. 

WEST VIRGINIA ----------Charleston. 

WISCONSIN ---------------Madison. 

WYOMING ----------------Cheyenne. 

9 

CONCLUSIONS 

Solution of today's complex hydrologic problems 

requires the timely availability of reliable groundwater data. The GWSI data base, in conjunction with 

the SYSTEM 2000 data base management system, 

provides these reliable and unbiased ground-water 

data for the hydrologist or planner who requires 

quick and easy access to them. 

Standardization of input-retrieval procedures and 

data formats exists in the GWSI for all data, and the 

techniques of manipulating the ground-water data 

are the same throughout the United States. The goals 

of the Survey in establishing a nationwide groundwater data base, thus, have been accomplished. 

REFERENCES CITED 

Baker, C. H., Jr., and Foulk, D. G., 1975, WATSTORE user's 

guide, volume 2, ground-water file: U.S. Geological Survey 

Open-File Report 75-589, 159 p. (Revised 1980.) 

Edwards, M.D., 1978, NAWDEX: A key to finding water dataNational Water Data Exchange: U.S. Geological Survey, 15 p. 

__ , 1980, Directory of assistance centers of the National Water 

Data Exchange (NA WDEX): U.S. Geological Survey OpenFile Report 80-1193, 14 p. 

Lang, S.M., and Leonard, A. R., 1967, Instructions for using the 

punchcard system for the storage and retrieval of groundwater data: U.S. Geological Survey open-file report, 93 p. 

MRI Systems Corp., 1974a, SYSTEM 2000 reference manual: 

Austin, Tex. 

, 1974b, SYSTEM 2000 NATURAL LANGUAGE 

--re-f-er-ence manual for IBM releases: Austin, Tex. 

____ , 1974c, SYSTEM 2000 report writer feature: Austin, 

Tex. 

____ , 1979, SYSTEM 2000-The language specification 

manual for the (PL/1 or COBOL) programing language, extension (PLEX) for IBM OS/VS: Austin, Tex. 

U.S. Environmental Protection Agency, 1973, Water quality 

control information system: STORET: Washington, D.C., 

U.S. Government Printing Office. 

U.S. Geological Survey, 1981, United States Geological Survey 

Yearbook, Fiscal year 1980: U.S. Geological Survey, 161 p. 

*U.S. GOVERNMENT PRINTING OFFICE: 1982-361-614/44