Data recorder Data recorder

Gage house Gage house

Pressure transducer and temperature 

sensor connected to real-time network Pressure transducer 

and temperature 

sensor connected to 

real-time network

Orifice

Data recorder transmission to satellite

Radio transmitter sends data to recorderRadio transmitter sends data to recorder

Network thermistor connected 

to real-time network

U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2012–3054 

June 2012 Printed on recycled paper

Demonstrating Usefulness of Real-Time Monitoring at Streambank 

Wells Coupled with Active Streamgages—Pilot Studies in 

Wyoming, Montana, and Mississippi

Introduction

Groundwater and surface water in many cases are considered separate resources, but there is growing recognition of 

a need to treat them as a single resource (Winter and others, 

1998; Alley and others, 1999). For example, groundwater 

inflow during low streamflow is vitally important to the health 

of a stream for many reasons, including buffering temperature, 

providing good quality water to the stream, and maintaining flow for aquatic organisms. The U.S. Geological Survey 

(USGS) has measured stream stage and flow at thousands of 

locations since 1889 (Gohn, 2004) and has the ability to distribute the information to the public within hours of collection 

(Nielsen and Norris, 2007; Cunningham, 2001), but collecting 

shallow groundwater data at co-located measuring sites is a 

new concept.

Recently developed techniques using heat as a tracer to 

quantify groundwater and surface-water exchanges (Stonestrom and Constantz, 2004) have shown the value of coupling 

these resources to increase the understanding of the water 

resources of an area. In 2009, the USGS Office of Groundwater began a pilot study to examine the feasibility and utility of widespread use of real-time groundwater monitoring 

at streambank wells coupled with real-time surface-water 

monitoring at active streamgages to assist in understanding the 

exchange of groundwater and surface water in a cost effective 

manner. 

Approach

All sites selected for this pilot study have year-long 

operation and are located in areas expected to have regional 

groundwater flow to or from the stream. Seven sites were 

selected to test the concept over a range of stream settings―

from a small stream in mountainous Wyoming, to a midsized 

intermontane river in Montana, to a large river in the Mississippi Delta. Although the variety of site types dictated some 

variations in site-specific equipment, all observation wells 

were similarly constructed, with well installation 15 to 30 feet 

from the edge of the streambank and completed to a depth of 

10 feet below the estimated lowest level of the water table. As 

such, the well provides an indication of the hydraulic head at a 

specific depth beneath the streambed and does not necessarily 

indicate the elevation of the water table adjacent to the stream.

 The streambank observation wells were instrumented 

to measure water level and temperature at the bottom of the 

well at 15-minute intervals using a pressure transducer and 

temperature sensor. Stream temperature was measured using 

a network thermistor placed in the stream (fig. 1). All data 

were collected by using USGS protocols (Cunningham and 

Schalk, 2011; Sauer and Turnipseed, 2010; Wagner and others, 

2006). The groundwater data and stream temperature data 

were collected and transmitted to the streamgage data recorder 

(fig. 1), which were then transmitted by way of satellite to a 

receiving station. Six of the sites were hard-wired to allow 

Figure 1. Design of generic observation well installation at streamgage featuring hard-wired recorder and radio-transmitted data for surface 

water and groundwater.
06227600

WYOMING

Wind River

Basin

Big Sunflower

River Basin

323045090484300

MISSISSIPPI

07288000

07288500

07288700

Figure 2. Location of 

U.S. Geological Survey 

streamgage at Wind River 

near Kinnear, Wyoming.

Figure 3. Location of 

U.S. Geological Survey 

streamgages on the 

Big Sunflower River, 

Mississippi.

for data transmission from the observation well to the data 

recorder. The exception was the Big Sunflower River at Sunflower in Mississippi, where the desired location for an observation well was across the stream from the data recorder in the 

streamgage. Because the distance between the observation well 

and streamgage was greater than available cable length, radio 

transmissions were used to transmit data from the well to the 

data recorder (fig. 1). Finally, all sites were surveyed to accurately compare elevations with each streamgage datum.

Transmittal of the groundwater data along with the stream 

data to a satellite and then to the Web for viewing in real time 

was an important component of the pilot study (U.S. Geological 

Survey, 2011). Real-time transmission of the data allows timecritical viewing and decisionmaking in response to dynamic 

changes in the near-stream environment, such as reversals in 

flow direction between groundwater and the stream. 

Most site visits to manually measure groundwater, to verify 

measurements with the data recorder, and to adjust the offset in 

the measured and recorded data (if necessary) coincided with 

the regularly scheduled visit for the streamgage. USGS personnel responsible for data collection at specific streamgages were 

responsible for the additional groundwater level and temperature 

measurements, and found the time commitment for the additional measurements to be small compared with the total time 

required to service the streamgage.

Pilot Study Site—Specific Observations

Coupled groundwater and surface-water data obtained for 

the sites were used in a different manner at each site to expand 

the understanding of the interaction. A short summary of how 

collected data were used for four sites in the pilot study are 

shown in figures 2 and 3. Detailed graphic data and results are 

presented for three focus sites: Flat Creek below Cache Creek, 

near Jackson, Wyoming (figs. 4–7), Big Sunflower River at 

Clarksdale, Mississippi (figs. 8–11), and Big Hole River near 

Melrose, Montana (figs. 12–15).

• During June 2011, the Wind 

River near Kinnear, Wyoming 

(streamgage 06227600; fig. 2), 

had near-record flows, resulting 

in flooding and damage to the 

streamflow stage instrumentation. This damage resulted in 

missing data during the highflow period. Because the groundwater level in the observation 

well closely followed the stream 

stage, the groundwater-level data 

were used to provide a better 

estimate of the peak streamflow 

at the site.

• Streamflow in the Big Sunflower 

River (streamgage 07288500; fig. 3) 

has been severely altered by loss of 

base flow owing to declining water 

levels in the underlying alluvial 

aquifer. Historically a predominantly 

gaining stream, the Big Sunflower 

River is now a predominantly losing stream. Flow augmentation is 

now required in the central reaches 

which flow over a cone of depression that has formed in the alluvial 

aquifer (Barlow and Clark, 2011). 

The addition of three coupled 

streambank observation wells at 

streamgages 07288500, 07288700, 

and 323045090484300 along the 

Big Sunflower River has allowed for 

an increased understanding of how 

groundwater/surface-water exchange varies temporally and 

longitudinally. These new data have provided water managers 

with valuable information that can be used to better manage 

and maintain streamflow.

Groundwater level is measured periodically 

to verify readings from pressure transducer 

in observation well. Photograph shows 

measurement taken at Wind River 

near Kinnear, Wyoming site.
6,091

6,093

6,095

6,097

6,099

6,101

6,103

6,105

6,107

11/23/2011 11/28/2011 12/3/2011 12/8/2011 12/13/2011 12/18/2011 12/23/2011 12/28/2011 Elevation, in feet above National Geodetic Vertical Datum of 1929 (NGVD 29)

Period of ice dam

Flat Creek stage elevation

EXPLANATION

Groundwater elevation

Streambed bottom

Ice begins damming creek

Base from U.S. Geological Survey

The National Map, 2012

N

WYOMING

Flat Creek Basin

0 0.5 1 MILE

0 0.5 1 KILOMETER

13018350

89

26

Jackson

Figure 4. Location of U.S. Geological Survey streamgage 13018350 at 

Flat Creek below Cache Creek, near Jackson, Wyoming.

Figure 5. View looking upstream on Flat Creek below Cache Creek, 

near Jackson, Wyoming, on November 21, 2000.

Figure 6. Elevations of Flat Creek below Cache Creek, near Jackson, Wyoming, creek stage, and groundwater level in nearby monitoring well.

30

35

40

45

50

55

11/23/2011 11/28/2011 12/3/2011 12/8/2011 12/13/2011 12/18/2011 12/23/2011 12/28/2011

Temperature, in degrees Fahrenheit

Flat Creek temperature

EXPLANATION

Groundwater temperature 17.6 feet

below streambed (measured in

observation well)

Ice begins damming creek

Flat Creek below Cache Creek, near Jackson, Wyoming (streamgage 13018350)

Figure 7. Water temperature of Flat Creek below Cache Creek, near Jackson, Wyoming, and groundwater in the nearby monitoring well.

Setting.—Flat Creek (figs. 4 and 5) originates in the mountains of 

western Wyoming. After the creek leaves the mountains, it flows 

through a large grassland and meadow. The observation well is 

15 feet from Flat Creek at the USGS streamgage. The well is completed 17.6 feet below the streambed in sand and gravel.

Flat Creek below Cache Creek near Jackson, Wyoming.—The 

drainage area at the streamgage is 129 square miles of primarily 

mountainous terrain with a mean annual streamflow of 78 cubic feet 

per second (water years 1989–2011; U.S. Geological Survey, 2011).

Data.—During most of the winter, the groundwater level does 

not closely follow the creek stage. Flat Creek commonly freezes 

during the winter, causing ice dams along the river, including the 

streamgage location, noted by the blue circles on figures 6 and 7. 

The extended period of freezing temperatures in early December 

caused an increase in the amount of water backed up by the ice 

dam. Around December 9, 2011, this higher stage and subsequent 

infiltration of surface water into the ground is indicated by the rise 

in the local groundwater level (fig. 6). The infiltration of near-freezing water also can be detected in groundwater temperature with a 

noticeable decline starting on December 12. Residential basements 

began flooding near the creek with rising groundwater levels. On 

December 13, a nearby thaw-well (a deep well that pumps relatively 

warm groundwater) was turned on, pumping warmer water into the 

creek to melt ice and allow the creek to flow freely again, decreasing water infiltrating into groundwater (Sean O’Malley, Town of 

Jackson, personal commun., 2012).

Practical applications.—This is an example of how real-time 

groundwater data can be used by water managers to be able to mitigate the effects of rising groundwater. Once this relation between 

surface water and groundwater is understood, a USGS service 

called WaterAlert (U.S. Geological Survey, 2012) can be used. The 

USGS WaterAlert service allows individuals to be notified when 

water data reach user-specified conditions. This will allow water 

managers to be notified when stream stage or groundwater levels 

are nearing critical elevations, and data can be viewed to potentially 

take action before a problem occurs and without needing a site visit.
N

Big Sunflower

River Basin

MISSISSIPPI

Clarksdale

streamgage

drainage

area

07288000

Clarksdale

322

0 0.5 1 MILE

0 0.5 1 KILOMETER

Base from U.S. Geological Survey

The National Map, 2012

130

135

140

145

150

155

Elevation, in feet above National Geodetic

Vertical Datum of 1929 (NGVD 29)

Big Sunflower River stage elevation

EXPLANATION

Groundwater elevation

Streambed bottom

Installation of downstream weir

10/1/2010 11/1/2010 12/1/2010 1/1/2011 2/1/2011 3/1/2011 4/1/2011 5/1/2011 6/1/2011 7/1/2011 8/1/2011 9/1/2011 10/1/2011

Figure 10. Elevation of Big Sunflower River at Clarksdale, Mississippi, river stage, and groundwater level in nearby monitoring well.

Big Sunflower River temperature

EXPLANATION

Groundwater temperature 6 feet

below streambed (measured

in observation well)

30

40

50

60

70

80

90

100

10/1/2010 12/1/2010 2/1/2011 4/1/2011 6/1/2011 8/1/2011 10/1/2011

Temperature, in degrees Fahrenheit

Figure 11. Water temperature of Big Sunflower River at Clarksdale, Mississippi, and groundwater in nearby monitoring well.

Big Sunflower River at Clarksdale, Mississippi (streamgage 07288000)

Setting.—The Big Sunflower River (figs. 8 and 9) is located 

within northwestern Mississippi. The drainage for streamgage 

07288000 previously was a flood plain to the Mississippi 

River and is dominated by irrigated agricultural land use. The 

observation well is 10 feet from the Big Sunflower River at 

the USGS streamgage. The well is completed 6 feet below the 

streambed in silt and fine sand.

Big Sunflower River at Clarksdale, Mississippi.—The 

streamgage represents a 108-square-mile drainage area with a 

mean annual streamflow of 166 cubic feet per second (water 

years 2009–2011; U.S. Geological Survey, 2011).

Data.—The Big Sunflower River at Clarksdale, Mississippi, 

is located near the headwaters of the Big Sunflower River 

and is in connection with the water table of the underlying 

aquifer. Water-level and temperature data (U.S. Geological 

Survey, 2011) indicate that the stream is gaining throughout 

most of the period of record (figs. 10 and 11). The groundwater 

temperature varies seasonally and is not affected by the stream 

temperature (fig. 11). Additionally, the installation of a weir 

in July 2011 is indicated by an increase in the stream stage 

(fig. 10). 

Practical applications.—Data from this site show that even 

in river systems where the stream is almost always gaining, 

the relation between the groundwater level and river stage is 

dynamic, and changes in a river system can potentially affect 

the groundwater levels.

Figure 9. Big Sunflower River at Clarksdale, Mississippi, on 

November 24, 2010.

Figure 8. Location of U.S. Geological Survey streamgage 07288000 at 

the Big Sunflower River at Clarksdale, Mississippi.
5,030

5,032

5,034

5,036

5,038

5,040

4/1/2010 5/1/2010 6/1/2010 7/1/2010 8/1/2010 9/1/2010 Elevation, in feet above National Geodetic Vertical Datum of 1929 (NGVD 29)

Big Hole River stage elevation

EXPLANATION

Groundwater elevation

Streambed bottom

Flood irrigation of nearby pasture

N

MONTANA

Big Hole River Basin

06025500

0 0.5 1 MILE

0 0.5 1 KILOMETER

Base from U.S. Geological Survey

The National Map, 2012

15

91

30

35

40

45

50

55

60

65

70

4/1/2010 5/1/2010 6/1/2010 7/1/2010 8/1/2010 9/1/2010

Temperature, in degrees Fahrenheit

Big Hole River temperature

EXPLANATION

Groundwater temperature 8.5 feet

below streambed (measured

in observation well)

Big Hole River near Melrose, Montana (streamgage 06025500)

Setting.—The Big Hole River Basin is an intermontane 

basin in southwestern Montana with grassland and irrigated 

agriculture in the valleys surrounded by mountains consisting of rangeland and coniferous forests (figs. 12 and 13). The 

observation well is 30 feet from the Big Hole River at the 

USGS streamgage. The well is completed 8.5 feet below the 

streambed in sand and gravel.

Big Hole River near Melrose, Montana.—The streamgage 

represents a 2,476-square-mile drainage area with a mean 

annual streamflow of 1,105 cubic feet per second (water 

years 1924–2011; U.S. Geological Survey, 2011).

Data.—Groundwater levels (U.S. Geological Survey, 2011) 

followed the general trend of the stream stage during most of 

the year (for example, April 1, 2010, through September 30, 

2010; fig. 14). Groundwater levels noticeably deviated from 

the stream stage during a period of local canal operation 

and the flood irrigation of a nearby pasture (fig. 15). Stream 

temperatures showed diel fluctuations and varied as much 

as 32 degrees Fahrenheit annually (fig. 15). Groundwater 

temperature at the bottom of the well lacked diel fluctuation, 

followed a dampened trend of the stream, and varied about 

9 degrees annually (fig 14). The groundwater temperature 

and water-level data may indicate minimal leakage from 

the stream to groundwater because water-level gradients 

were small and dynamic changes in temperature below the 

streambed were not observed. However, the seasonal change 

in groundwater temperature may indicate local recharge to 

the groundwater system through irrigation practices.

Practical applications.—Data from this type of site can be 

used by water-resource managers in agricultural settings 

where irrigation practices and the hydrologic response to 

groundwater and surface-water systems is of interest.

Figure 12. Location of U.S. Geological Survey streamgage 06025500 at 

the Big Hole River near Melrose, Montana.

Figure 13. Big Hole River near Melrose, Montana, on November 10, 

2010.

Figure 14. Elevation of Big Hole River near Melrose, Montana, river stage, and groundwater level in the nearby monitoring well.

Figure 15. Water temperature of the Big Hole River near Melrose, Montana, and groundwater in the nearby monitoring well.
What Value Does Real-Time Groundwater Monitoring Add 

to Streamgages?

This pilot study showed that coupled real-time monitoring 

of groundwater and surface water at streambank observation 

wells and streamgages can substantially enhance the information gained from a streamgage alone. The costs of the additional 

data collection, quality assurance, transmission of data, and 

additional maintenance incurred to collect the groundwater 

levels and the stream and groundwater temperatures added 

about 5 percent more to the cost of an established, year-round 

streamgage. Data from the coupled real-time observation wells 

and streamgages have been shown to be useful for:

• Determining the effects of irrigation practices on local 

groundwater levels. 

• Early warning of flooding from rapidly rising groundwater 

caused by infiltration from a stream.

• Determining an estimate of stream stage at sites where 

streamgages are damaged by floods.

• Understanding the groundwater/surface-water interactions 

and how changes to any part of the system, such as a weir 

installation, affect the dynamics of the interaction.

These types of data could be collected at selected 

streamgages across the United States and could be used for a 

variety of purposes, such as:

• Understanding the effects of groundwater/surface-water 

exchange on fisheries and other aquatic populations.

• Managing irrigation practices to minimize changes on 

instream flows to reduce potential effects on endangered species.

• Estimating water fluxes across the streambed by using waterlevel and temperature-based simulations.

• Real-time modeling of chemical fluxes moving between the 

groundwater and streams.

• Pairing with existing groundwater wells in a watershed to 

understand ecosystem dynamics and water exchange.

In summary, the pilot study has demonstrated that real-time 

groundwater monitoring at active streamgages is capable of 

rapidly providing a suite of four fundamental water characteristics—stream stage, groundwater level, surface-water temperature, and groundwater temperature—as combined resource tools 

available to the public, ranging from farmers to fisherman to 

teachers to water-resource managers, with only minor additional 

costs to existing real-time streamgages.

References Cited

Alley, W.M., Reilly, T.E., and Franke, O.L., 1999, Sustainability 

of ground-water resources: U.S. Geological Survey Circular 

1186, 79 p. (Also available online at http://pubs.usgs.gov/

circ/circ1186/.)

Barlow, J.R.B., and Clark, B.R., 2011, Simulation of water-use 

conservation scenarios for the Mississippi Delta using an 

existing regional groundwater flow model: U.S. Geological 

Survey Scientific Investigations Report 2011–5019, 14 p. 

(Also available online at http://pubs.usgs.gov/fs/fs-090-01/.)

Cunningham, W.L., 2001, Real-time ground-water data for 

the Nation: U.S. Geological Survey Fact Sheet 090–01, 2 p. 

(Also available online at http://pubs.usgs.gov/fs/fs-090-01/.)

Cunningham, W.L., and Schalk, C.W., compilers, 2011, 

Groundwater technical procedures of the U.S. Geological 

Survey: U.S. Geological Survey Techniques and Methods, 

book 1, chap. A1, 151 p. (Also available online at http://pubs.

usgs.gov/tm/1a1/.)

Gohn, K.K., compiler, 2004, Celebrating 125 years of the U.S. 

Geological Survey: U.S. Geological Survey 1274, 56 p. (Also 

available online at http://pubs.usgs.gov/circ/2004/1274/.)

Nielsen, J.P., and Norris, J.M., 2007, From the river to you―

USGS real-time streamflow information: U.S. Geological 

Survey Fact Sheet 2007–3043, 4 p. (Also available online at 

http://pubs.usgs.gov/fs/2007/3043/.)

Sauer, V.B., and Turnipseed, D.P., 2010, Stage measurement 

at gaging stations: U.S. Geological Survey Techniques and 

Methods, book 3, chap. A7, 45 p. (Also available online at 

http://pubs.usgs.gov/tm/tm3-a7/.)

Stonestrom, D.A., and Constantz, Jim, 2004, Using temperature 

to study stream-ground water exchanges: U.S. Geological 

Survey Fact Sheet 2004–3010, 4 p. (Also available online at 

http://pubs.usgs.gov/fs/2004/3010/.)

U.S. Geological Survey, 2011, National Water Information System, accessed December 15, 2011, at http://nwis.waterdata.

usgs.gov/nwis.

U.S. Geological Survey, 2012, USGS WaterAlert, accessed 

January 9, 2012, at http://water.usgs.gov/wateralert/.

Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, 

B.A., 2006, Guidelines and standard procedures for continuous water-quality monitors—Station operation, record computation, and data reporting: U.S. Geological Survey Techniques and Methods, book 1, chap. D3, 51 p. (Also available 

online at http://pubs.usgs.gov/tm/2006/tm1D3/.)

Winter, T.C., Harvey, J.W., Franke, O.L., and Alley, W.M., 

1998, Ground water and surface water―A single resource: 

U.S. Geological Survey Circular 1139, 79 p. (Also available 

online at http://pubs.usgs.gov/circ/circ1139/.)

By Cheryl A. Eddy-Miller, Jim Constantz, Jerrod D. Wheeler, 

Rodney R. Caldwell, and Jeannie R.B. Barlow

For more information:

http://wy.water.usgs.gov/projects/ogw