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U.S. Department of Interior

U.S. Geological Survey

 May 2003

District Web Site: http://il.water.usgs.gov/ Compiled by D.M. Ayers

MESSAGE FROM ROBERT R. HOLMES, JR., ILLINOIS DISTRICT CHIEF

The 10th anniversary of the Great Flood of 1993 on the Mississippi River and tributaries (fig. 1) is this summer. The awe that 

I felt in witnessing, as a Hydraulic Engineer for the U.S. Geological Survey (USGS) in the Missouri District, that historic flood 

firsthand still is fresh in my mind. The 1993 flood was both a tragedy (in the destruction of property and affect on lives), and a 

fascinating opportunity to collect data and conduct studies of an extreme flood (possibly a once-in-a-career opportunity). The 

flood occurred over approximately a 4-month period (May through August 1993 on the Middle Mississippi River), but USGS 

staff from across the entire country collected data and conducted studies well into calendar year 1994. Various aspects of the 

flood (including flow, sediment and water-quality data) are documented in multiple chapters of USGS Circular 1120. The dedication of USGS staff, including Hydrologic Technicians, Hydrologists and Hydraulic Engineers, Administrative Officers, and 

many others, was exceptional during the 1993 flood. The dedication of USGS staff always has been an important aspect of 

USGS service to the Nation. A recent example of this dedication is the USGS efforts during the 2002 flooding in Illinois. Illinois 

District personnel spent hundreds of hours collecting data often under difficult conditions during the flood. A short article on this 

flood is presented on page 5. A USGS Open-File Report thoroughly describing the 2002 flood is planned to be available in early 

summer.

Water Resources Update

Illinois District Newsletter

TABLE OF CONTENTS

The 10th Anniversary of the Great 

Flood of 1993 on the Mississippi 

River and Tributaries . . . . . . . . . . 1

Hydrogeologic Assessment of 

Campton Township. . . . . . . . . . . . 2

When is the Next Earthquake in 

Illinois?. . . . . . . . . . . . . . . . . . . . . 4

Flooding in Illinois, April—June 

2002 . . . . . . . . . . . . . . . . . . . . . . . 5

Cooperator Spotlight . . . . . . . . . . 6

Employee Spotlight . . . . . . . . . . . 6

WaterWatch . . . . . . . . . . . . . . . . . 7

From the Mailbag . . . . . . . . . . . . . 8

Illinois District Publications. . . . . 8

Figure 1. U.S. Geological Survey (USGS) personnel measuring flow at the 

Mississippi River at Thebes during the 1993 flood (USGS personnel are in the 

monorail system, located below the bridge deck, lowering the flow meter and 

300-pound weight by cable to the river.)
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HYDROGEOLOGIC ASSESSMENT OF CAMPTON TOWNSHIP

BY

ROBERT T. KAY, HYDROLOGIST

Campton Township in Kane County, 

north-central Illinois (fig. 1), has experienced substantial residential development in the past 20 years. This 

development is expected to continue. 

Water needs for this residential development have been supplied exclusively by 

ground water, primarily from residential-supply wells, although public-supply systems serve the needs of some 

residents. Ground-water withdrawals for 

residential use have exceeded recharge 

in some of the residential-supply aquifers in parts of the township, resulting in 

large decreases in water levels and 

water-supply interruptions. These interruptions have necessitated lowering of 

pumps and deepening of wells at substantial expense to the affected homeowners. Continued residential 

development will increase the demand 

on the ground-water resources, potentially increasing interruptions in water 

supply. As alternate sources of water 

supply are either unavailable (surface 

water) or would require development of 

expensive infrastructure (deeper aquifers), it is essential that the current aquifers used for water supply be more 

efficiently utilized. To this end, the 

Campton Township Board of Trustees 

has requested that the USGS, Illinois 

and Indiana Districts, characterize the 

ground-water resources in the township 

and, based on this assessment, develop a 

computer model that can be used to 

assess the effects of present and proposed residential development on 

ground-water resources. The computer 

model also will enable the effects of 

changes in climatic conditions, particularly drought, on ground-water 

resources to be predicted.

Previously published reports pertaining to the hydrogeology in the township and surrounding areas and drillers’ 

logs for the township and parts of the 

surrounding area were reviewed. These 

data show that four hydrogeologic units 

are used for residential-water supply in 

Campton Township—the unconsolidated sand-and-gravel deposits composing the Shallow and Deep Glacial Drift 

aquifers; the shallow bedrock of the 

Alexandrian Series and the Maquoketa 

Group composing the AlexandrianMaquoketa aquifer; the Galena and Platteville Groups composing the GalenaPlatteville aquifer; and the sandstones 

composing the Ancell aquifer (fig. 2).

During the summer of 2002, water 

levels were measured in each of the 

aquifers used for residential supply. 

These water levels were, and compared 

to historical measurements, taken at the 

time of drilling and during a 1995 USGS 

survey. Water levels in wells open to the 

Alexandrian-Maquoketa aquifer showed 

the largest changes between 1995 and 

2002, increasing by as much as 30 feet 

(ft) in a small area in the eastern part of 

Figure 1. Location of Campton Township, Kane County, Illinois.
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the township and decreasing by as much 

as 15 ft in part of the northeastern part of 

the township. Water levels in this aquifer 

declined by 5 ft or more in more than 

half of the wells measured. Wells open 

to the Deep and Shallow Glacial Drift 

aquifers showed substantially less 

change in water levels than wells open 

to the Alexandrian-Maquoketa aquifer. 

Water levels in 30 of 40 wells, measured 

in 1995 and 2000 open to the Deep and 

Shallow Drift aquifers were within 5 ft. 

Declines of 5 ft or more were measured 

in 8 of these 40 wells, whereas increases 

of 5 ft or more were measured in 2 of 

these wells. Water levels in wells open 

to the Galena-Platteville and Ancell 

aquifers showed no consistent trends in 

water levels.

Flow was measured at several 

points in each of the major streams in 

the township during the summer and fall 

of 2002 to determine the contribution of 

ground-water base flow to surface water 

so that recharge to the shallow groundwater-flow system can be estimated. 

Streamflow showed an overall decrease 

over the period of measurement and 

showed that the streams typically were 

gaining. Ground-water recharge to surface water resulted in less than 0.1 cubic 

feet per second (ft3

/s) of flow at Virgil 

Ditch in the northwestern part of the 

township during most of the period of 

measurement. As the name implies, Virgil Ditch is not a natural surface-water 

body. Ground-water recharge to surface 

water, with an apparently small contribution from wastewater, resulted in 

more than 1 ft3

/s at Ferson and Mill 

Creeks in the eastern part of the township.

To support the data already collected, additional work will be performed to complete the resource 

assessment. Constant-discharge aquifer 

tests will be performed during the spring 

and summer of 2003 to determine the 

transmissivity and storativity of the residential-supply aquifers. Geophysical 

logging will be conducted in residentialsupply wells open to the Ancell aquifer 

during the summer of 2003 to further 

characterize the hydraulic properties of 

the aquifers accessed by these wells, 

estimate of the potentiometric surface of 

the Ancell aquifer, and provide an estimate of the volume of water draining out 

of the upper bedrock deposits into the 

Ancell aquifer through these open boreholes.

All of the available information then 

will be used to develop a ground-waterflow model of the residential-supply 

aquifers. The model will be used to predict the effects of current and future 

pumping on water levels in residentialsupply aquifers and local wetlands, as 

well as on the amount of streamflow in 

Campton Township. The model will be 

used as a tool by local government agencies to assist in the management of 

water resources.

Figure 2. Generalized geohydrologic column showing stratigraphy and geohydrologic units, Campton Township, Illinois.
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Illinois is not thought of as a State 

prone to earthquakes, but many people 

throughout the State have experienced the effects of earthquakes in 

2002. An earthquake with it’s epicenter in Alaska caused muddied wells in 

various counties in northern Illinois in 

November, while an earthquake with 

it’s epicenter near Evansville in southwestern Indiana shook people in 

southern Illinois in June. The largest 

earthquakes in historical time in the 

continental United States occurred just 

south of Illinois near New Madrid, 

Missouri in 1811 and 1812. Earthquake effects potentially can occur in 

the entire State of Illinois (fig.1). 

What other earthquakes have occurred 

in Illinois, and where? When will the 

next earthquake occur in Illinois, and 

how big will it be?

Earthquakes in Illinois can originate from a number of source areas. 

There have been historical records 

since 1795 of earthquakes in Illinois, 

primarily in three general areas. There 

is potential for further earthquake 

activity in all three areas.

The area with the most potential 

for damage, in fact, the most potential 

for damage to the Nation east of the 

Rocky Mountains, is the New Madrid 

seismic zone that extends from Cairo, 

Illinois to Arkansas. This area has had 

repeated earthquakes since 1811–

1812, but none as severe as the 1811–

1812 earthquakes, which had estimated magnitudes around 8.0 (Richter 

scale). The largest recent (since 1900) 

earthquake in Illinois occurred in this 

area on November 9, 1968, in southern Illinois. The 5.5 magnitude earthquake caused cracked foundations, 

toppled chimneys, broken glass, and 

tipped gravestones, along with other 

reported damage.

The Wabash Valley seismic zone 

is another active seismic area located 

in southern Illinois and southern Indiana. Moderate earthquakes have 

occurred as frequently in the Wabash 

Valley area as the New Madrid area. 

WHEN IS THE NEXT EARTHQUAKE IN ILLINOIS?

BY

WILLIAM MORROW, HYDROLOGIST

Figure 1. Potential damage from earthquake effects in Illinois. Modified from Illinois 

Emergency Management Agency, “Illinois Earthquake Zones” Web site, last accessed 

February 18, 2003: http://www.state.il.us/iema/Prep/earth_zonemap.htm.
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The last major earthquake in this area 

was on June 18, 2002, when a 5.0 

magnitude earthquake cracked chimneys and broke glass in Evansville, 

Indiana. The earthquake was felt in 

Illinois, but caused no reported damage.

Northern Illinois also is an area of 

seismic activity. The largest fault 

structure in the area is the Sandwich 

fault, trending approximately northwest from Kendall County to Ogle 

County, with up to an 800-foot displacement. The fault has not been historically active. However, nearby 

geological structures, such as the La 

Salle Anticline and the Peru Monocline, are likely related to earthquake 

origins. In 1999, a 3.5 magnitude 

earthquake occurred near Dixon, Illinois. No damage was reported, but 

past earthquakes in the 20th century in 

the area have caused cracked chimneys and wall plaster, along with other 

damage.

Can these earthquakes be predicted? There is no reliable way today 

to predict exactly when and where 

earthquakes will occur, or how large 

these earthquakes will be, but the 

USGS has calculated long-range 

earthquake probability forecasts in 

seismically active areas. The USGS 

and the Center for Earthquake 

Research and Information at the University of Memphis have examined 

the New Madrid seismic area and have 

estimated that the probability of a 7.5–

8.0 magnitude earthquake, or as large 

as the earthquakes of 1811–1812, 

occurring in the next 50 years is from 

7 to 10 percent. The probability of an 

earthquake of a magnitude of 6.0 or 

larger occurring in the next 50 years is 

from 25 to 40 percent. The potential 

for damage to man-made structures 

likely to be affected by earthquakes of 

these magnitudes is high because the 

New Madrid seismic area overlies 

thick unconsolidated sediments, which 

can amplify shaking motion as the 

earthquake travels from hard bedrock 

to the thick unconsolidated sediments.

For more information on earthquake hazards in the central United 

States, the USGS Fact Sheet FS-131-

02, “Earthquake Hazard in the Heart 

of the Homeland,” is available on the 

Web at http://pubs.usgs.gov/fs/fs-131-

02/fs-131-02.pdf. Other earthquake 

information sources available on the 

Web are the Center for Earthquake 

Research and Information at the University of Memphis at 

http://www.ceri.memphis.edu/ and the 

USGS National Earthquake Information Center at http://neic.usgs.gov/.

FLOODING IN ILLINOIS, APRIL—JUNE 2002

BY

CHARLES F. AVERY, HYDROLOGIST

Widespread flooding occurred throughout most of Illinois in spring 2002 as a result of multiple, intense rainstorms that 

moved across the State during an extended period from the third week in April through the month of May in central and southern Illinois, the first week in June in northern Illinois, and the second week in June in west-central Illinois. Because the flooding resulted from multiple rainfall events stretched along successive frontal boundaries, many of which stalled as they passed 

over Illinois, the scale of flooding was highly variable in time and intensity throughout the State.

Total amounts of rain for the 2-month period from mid-April to mid-June 2002 ranged from less than 8 inches in extreme 

northeastern Illinois to over 23 inches in the central part of the State. During the flooding, numerous highways and bridges 

were washed out, inundated, or threatened by high water, levees were breached, agricultural land and low-lying residential 

areas were inundated for extensive periods of time, and several deaths were attributed to lightning strikes, tornado damage, and 

drownings in the floodwaters.

The USGS operates discharge or stage-recording streamflow-gaging stations throughout Illinois, in drainages just 

upstream of the State, and on the Mississippi, Ohio, and Wabash Rivers. Most of the stations have 10 or more years of record 

and, subsequently, have an established flood-frequency distribution relating annual maximum instantaneous peak flows to 

recurrence intervals at the station.

New maximum instantaneous discharge was recorded at 12 streamflow-gaging stations during this flood period, and new 

maximum stage was recorded at 15 stations. Flood stage was exceeded for at least 1 day during this 2-month period at 67 of the 

82 stations with established flood-stage elevations determined by the National Weather Service. Of the 162 streamflow-gaging 

stations for which flood-frequency distributions have been determined, a 5-year or greater flood discharge was recorded at 87 

stations. A 100-year or greater flood discharge was recorded at six stations.

A Federal Disaster Declaration was issued May 21, 2002, by President George W. Bush that provided aid to individuals, 

families, and businesses in 30 counties in southern Illinois affected by storms, tornadoes, and flooding that began April 21. An 

amendment to that Declaration issued May 30, 2002, expanded the area to include 68 counties of central and southern Illinois. 

On June 6, 2002, disaster assistance was expanded to include aid for local governments in 33 counties. The aid to local governments later was expanded on June 21, 2002, to 38 counties. By June 28, 2002, the amount of disaster assistance to individuals 

and businesses had exceeded $10.3 million.
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Winnebago County covers an area 

of approximately 520 square miles in 

north-central Illinois. The county, with 

a total population of approximately 

275,000, is located approximately 90 

miles west of Chicago and 90 miles 

east of the Mississippi River at the 

Iowa State line. The city of Rockford 

(second largest city in Illinois by population, approximately 175,000) is the 

county seat.

Various important waterways in 

Winnebago County are utilized for 

commercial, industrial, and recreational purposes. The Rock River 

(largest river flowing through the 

county) flows from north to south. 

The Pecatonica River flows from west 

to east in the western/northwestern 

portion of the county and empties into 

the Rock River at Rockton. The Sugar 

River flows from north to south and 

drains into the Pecatonica River near 

Harrison. In southeastern Winnebago 

County, the Kishwaukee River empties into the Rock River just south of 

Rockford. The Rock River drains 

approximately 7,700 square miles 

(calculated to the southern Winnebago 

County line) in northern Illinois and 

southern Wisconsin. Major and minor 

flooding has resulted in these and 

other county waterways, especially 

during the last 10-20 years.

The Winnebago County Sheriff’s 

Office is responsible for patrolling and 

monitoring the waterways, and the 

Winnebago County Emergency Service and Disaster Agency also is 

responsible for monitoring and for all 

emergency coordination concerning 

the waterways. Little information was 

available to the county for monitoring 

of the waterway and other waterresources activities. Because of the 

need for this information, the Sheriff’s 

Office and Disaster Agency met with 

the USGS-Illinois District, the U.S. 

Army Corps of Engineers, and the 

National Weather Service in 2000 to 

discuss improvements to streamflow 

monitoring and other activities. Meeting results led to the establishment of 

three streamgaging stations in the 

county. Two daily-discharge stations 

were established by the USGS-Illinois 

District in 2002 on the Pecatonica 

River near Meridian Road and the 

Rock River near Latham Road. A third 

stage-only station was established by 

the USGS-Illinois District in 2002 on 

the Rock River near Auburn Street 

Bridge at the end of the pool created 

by a dam maintained and operated by 

Commonwealth Edison, a major 

power supplier in the area.

Funding for the installation and 

maintenance of streamgaging stations 

was obtained from State grants 

awarded to the county, Commonwealth Edison, and the USGS. Also, 

Winnebago County provided right-ofway to county property adjacent to 

bridges where stations are located, and 

the Winnebago County Highway 

Department provided equipment for 

station construction. Data collected at 

the three stations, as well as approximately 180 other streamgaging stations located throughout Illinois, are 

available on a real-time basis at the 

USGS Illinois District Web site. The 

National Weather Service uses these 

data to prepare flood warnings and 

forecasts as well as other uses (for 

example, implement mitigation efforts 

during droughts and for safe boating 

and recreation). Flood warnings and 

forecasts allow local, State, and Federal officials to take early actions, 

such as evacuations and road closures.

Close cooperation among Winnebago County and various State, Federal, and private organizations has 

been vital to the successful installation, maintenance, and operation of 

the streamgaging stations.

COOPERATOR SPOTLIGHT

WINNEBAGO COUNTY

EMERGENCY SERVICE AND DISASTER AGENCY, SHERIFF’S OFFICE

Perry Draper has been a fulltime employee with the USGS-Illinois District, since 1987. He began 

working as a student in the Mt. Vernon Field Office, while attending 

Rend Lake Jr. College. Perry 

received his B.S. in Geology from 

Eastern Illinois University in 1984.

Perry has installed, serviced, 

and worked records for many 

streamgaging stations throughout 

Illinois. His field area, over the 

years, has included streamgaging 

stations on or connected to the Mississippi, Ohio, Illinois, Kaskaskia, 

Embarras, Wabash, and Big Muddy 

river systems.

Perry transferred to the Urbana 

District Office in 2000 from Mt. 

Vernon. While continuing his 

streamgaging duties, he has 

installed, maintained, and collected 

data at stream rapid assessment 

project sites throughout the State. 

Recently, he has been involved with 

collecting and processing sediment 

data in the Illinois District. He has 

been selected to attend a USGS 

National Training Center course, 

“Sediment Data Collection Techniques,” this year.

Perry and his wife, Michelle, 

reside with their daughter, Megan, in 

Champaign, Illinois. Perry enjoys 

spending time with his family, tennis, and scuba diving.

EMPLOYEE SPOTLIGHT

PERRY DRAPER

HYDROLOGIC TECHNICIAN
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WaterWatch is the official 

USGS Web site for maps and 

graphs, showing real-time 

streamflow conditions in the 

United States and Puerto Rico. 

WaterWatch maps depict current 

streamflow as color-coded dots at 

about 3,000 streamgages 

throughout the Nation. Only stations having at least 30 years of 

continuous record are used in the 

maps to ensure that the calculated 

streamflows are representative of 

historical conditions. The WaterWatch Web site is available at 

http://water.usgs.gov/waterwatch/.

WaterWatch features a pointand-click interface allowing users 

to retrieve maps and graphs of 

real-time stage and discharge data 

for individual stations. From the 

National map, you can click on a 

State to find State data and click 

further to find real-time data at an 

individual streamgage. This feature facilitates rapid assessment 

of both general and specific 

water-resources conditions. 

WaterWatch also serves as a 

geospatial front end to 

NWISWeb, the USGS online 

National Water Information System that provides access by home 

or office computer to real-time 

and historical surface-water, 

ground-water, and water-quality 

data. Access to data (including 

real-time streamflow and historical flood peaks) by NWISWeb 

can be obtained at http://waterdata.usgs.gov/nwis/. To provide 

users with a broad perspective on 

short-term and long-term streamflow conditions and variations, 

WaterWatch maps and graphs are 

organized into three distinct categories: real-time, daily, and 7-day 

average streamflow. The latter 

category is particularly useful for 

identifying regions undergoing 

prolonged wet and dry periods.

USGS has provided real-time 

streamflow and historical streamflow data on the Web for the last 

5–10 years. WaterWatch marks 

the first time that these data have 

been combined with a geospatial 

or map-based front end. Users 

also can access other types of 

water data including historical 

water-quality data from rivers and 

aquifers, historical ground-waterlevel data, and real-time water 

quality, precipitation, and 

ground-water levels.

Daily WaterWatch maps also 

can be viewed as animations. The 

daily maps are grouped into 

monthly animations dating back 

to June 1999. These animations 

provide a useful visual characterization of streamflow changes 

from day to day, particularly in 

showing the response of a river 

during a large storm. Animations 

also show the speed at which a 

drought can intensify along rivers 

and streams.

WaterWatch and NWISWeb 

are integral parts of the USGS 

mission to disseminate important 

water-quality and quantity data to 

the public. These data can help 

water managers, engineers, scientists, emergency managers, recreational water users and utilities 

to:

• evaluate current water supplies and plan for future supplies,

• forecast floods and droughts,

• operate reservoirs for hydropower, flood control, or water 

supplies; evaluate and control water quality, navigate 

rivers and streams,

• safely fish, canoe, kayak, or 

raft.

WATERWATCH

BY

ANGEL MARTIN, JR., SUPERVISORY HYDROLOGIST
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From the Mailbag

If you have comments about 

our newsletter or our Web site, 

please use the form on the back 

page. Comments also can be sent 

to dc_il@usgs.gov.

“All good news. Particularly 

liked info on watershed studies: 

Judy’s branch. I’m not yet discerning or specialized enough to 

desire any changes, so just keep 

up the good work...”

“Thank you very much for 

your help, and those sites 

worked out perfectly!!”

“Thank you for your quick 

response to my question. It is 

very strange that my well problems and my neighbors happened shortly after the quake. I 

have been told that our water 

supply originates from the 

Alaska area. I have had my well 

treated. The water is fine now. I 

will be contacting the two other 

source which you provided. I 

appreciate your opinion and help 

in this matter.”

“I just wanted to write and tell 

you how impressed I am with 

your CEE 398 FM lecture 

notes/class handouts that I found 

on the web yesterday. I printed 

cle-Tracking Analysis of 

Ground-Water Flow Underlying Belvidere, Illinois, by P.C. 

Mills, K.J. Halford, and R.P. 

Cobb

WRIR 02-4213, Use of Isotopes to 

Identify Sources of Ground 

Water, Estimate GroundWater-Flow Rates, and Assess 

Aquifer Vulnerability in the 

Calumet Region of Northwestern Indiana and Northeastern 

Illinois, by R.T. Kay, E. R. 

Bayless, and R.A. Solak

“At the Printer”

The following District publications 

are not yet available for distribution.

OFR 02-487, Flooding in Illinois, 

April–June 2002, by C.F. 

Avery and D.F. Smith

WRIR 02-4097, Pesticides in Surface Water in the Lower Illinois River Basin, 1996–98, by 

R.B. King

WRIR 02-4293, Anthropogenic 

Constituents in Shallow 

Ground Water in the Upper 

Illinois River Basin, by W.S. 

Morrow

ILLINOIS DISTRICT

PUBLICATIONS

Listed below are publications that 

were published recently. Federal 

Fiscal Year (FY) covers October 1 

through September 30. District 

policy is to provide copies of our 

publications to requestors at no 

cost as long as the publication is in 

stock in the District office. To 

obtain copies of the following, or 

any other Illinois District publication, you may contact Donna Ayers 

at (217) 344-0037, extension 3053 

or by email at dmayers@usgs.gov.

FY 2003

WRIR 01-4121, Monitoring and 

Analysis of Combined Sewer 

Overflows, Riverside and 

Evanston, Illinois, by A.M. 

Waite, N.J. Hornewer, and G.P. 

Johnson

WRIR 02-4062, Delineation of the 

Troy Bedrock Valley and Partiout Volume 1 on surface water 

data collection and gave it a 

thorough once-over. I was hired 

as a tech in the ... district about a 

year and a half ago and have 

since been promoted to hydrologist... I wish I would have had 

something as clear, concise and 

up to date as what you have 

taken the time to put together. I 

feel that a new hire would be 

more apt to read and digest your 

manual as opposed to WS 2175 

vols 1 and 2. I have suggested 

that your manual be required 

reading material for all new 

hires. Thanks again for doing 

such an outstanding job.”