The U.S. Geological Survey (USGS), in cooperation adopt water-quality criteria that protect those uses (Public 

with the Wyoming Department of Environmental Law 92-500). In even numbered years, the State of 

Quality (WDEQ), is collecting water samples for Wyoming reports to the U.S. Environmental Protection 

analysis of fecal coliform bacteria at 18 stream sites as Agency (USEPA) the status of its waters through the 

part of a statewide network. Contamination by bacteria 305(b) Water Quality Assessment. Waters that do not meet 

of fecal origin in streams where contact recreation is a water-quality criteria for their designated use are listed as 

designated water use is a concern because of potential required under section 303(d) of the CWA. In Wyoming, 

public-health risk from the presence of enteric patho- streams placed on the section 303(d) list as not fully 

gens. Fecal coliform concentrations are temporally and meeting their designated uses must either show at least two 

spatially variable in Wyoming streams-concentrations exceedences of a numeric water-quality standard within a 

ranged from less than 1 to 45,000 colonies per 100 single 3-year period in the previous 5 years, or clearly 

milliliters of water during 1990-99. Fecal coliform exhibit the failure to achieve State narrative water-quality 

concentrations were less than the water-quality crite- standards (J. Smith, Wyoming Department of Environrion of 400 colonies per 100 milliliters in 83 percent of mental Quality, written commun., 2000). The State of 

the samples, indicating fecal coliform contamination is Wyoming assessed nearly 3,000 stream miles for the 

not a widespread problem in these Wyoming streams. 305(b) report for 2000 (Wyoming Department of EnvironHowever, 14 of the 18 monitoring sites had at least one mental Quality, 2000). In general, Wyoming streams fully 

sample in which the fecal coliform concentration support their designated use. Impairments identified for 

exceeded 400 colonies per 100 milliliters at some time Wyoming streams on the 303(d) list for 2000 include: fecal 

during the 10-year period. Fecal coliform concentra- coliform bacteria, trace metals, nutrients, salinity, physical 

tions generally are higher during April through degradation, and oil deposits (Wyoming Department of 

September than during October 

through March. The higher concentrations coincide with the time period 

when the public-health risk is higher 

because summer months are when 

contact recreation use is more likely 

occurring. Fecal coliform concentrations were positively correlated with 

discharge and stream temperature 

and generally were negatively correlated with pH, specific conductance, 

and dissolved oxygen.

The Clean Water Act (CWA) establishes a process for States to develop 

information on water quality. It requires 

States to designate uses for each 

surface-water body in the State and 

U.S. Department of the Interior

U.S. Geological Survey

Water-Resources Investigations Report 00-4198

Cheyenne, Wyoming 2000

Occurrence of Fecal Coliform Bacteria in Selected Streams in Wyoming,

1990-99

ABSTRACT

1

By Melanie L. Clark and Jodi R. Norris

Prepared in cooperation with the

Wyoming Department of Environmental Quality

science for a changing world

INTRODUCTION
Environmental Quality, 2000). Fecal coliform bacteria was biosolids to fields, crop irrigation from contaminated 

the most commonly listed impairment in 2000-the State storage ponds;

assessed about 250 miles of stream as being impaired for Urban/Residential-failed septic systems, pet waste, 

contact recreation use. landfill leakage;

Recreational-direct discharge of water-craft sewage; 

Bacteriological analyses are used to assess the sanitary and

quality of water because the presence of certain bacteria is Wildlife waste (Wilhelm and Maluk, 1998).

an indicator of the presence of fecal material from warmblooded animals (U.S. Environmental Protection Agency, Historically, the USEPA studies determined that statisti1976). High concentrations of fecal indicator bacteria in cally significant swimming-associated gastrointestinal 

waters where humans have recreational contact may illness may occur when concentrations of fecal-coliform 

present a risk of infection from other pathogenic microor- indicator bacteria are 400 colonies per 100 milliliters of 

ganisms. Indicator bacteria, like fecal coliform, do not water (cols/100 mL) or higher (U.S. Environmental 

necessarily cause illness but are found in association with Protection Agency, 1986).

pathogenic microorganisms. High levels of indicator 

bacteria can indicate the possible presence of pathogens As part of a program to monitor long-term water 

that cause such waterborne diseases as gastroenteritis, quality in Wyoming, the U.S. Geological Survey (USGS), 

bacillary dysentery, typhoid fever, and cholera (Myers and in cooperation with the Wyoming Department of EnvironSylvester, 1997). The origin of bacterial contamination mental Quality (WDEQ), monitors fecal coliform indicator 

can be from point or nonpoint sources. Point sources are bacteria at 18 sites statewide on major rivers and their 

from single locations, like the end of a pipe. The primary tributaries (table 1). The purpose of this report is to 

point source of bacterial contamination is sewage- describe the occurrence of fecal coliform in streams in 

treatment-plant outfalls. Nonpoint sources are diffuse in Wyoming for the period 1990-99. This report summarizes 

nature and include: data by water year which is the period from October of the 

previous year to September of the specified year. Seasonal 

Agricultural-animal waste, application of manure and variations are summarized for eight sites that are identified 

2

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

06232600

06235500

06264700

06274300

06276500

06284500

06302200

06304500

06305500

06320210

06426500

06428050

06669050

06756060

09222000

09224050

10038000

13027500

Popo Agie River at Hudson Siding, near Lander, Wyo.

Little Wind River near Riverton, Wyo.

Bighorn River at Lucerne, Wyo.

Bighorn River at Basin, Wyo.

Greybull River at Meeteetse, Wyo.

Bitter Creek near Garland, Wyo.

Big Goose Creek above Park Creek, near Sheridan, Wyo.

Little Goose Creek at Sheridan, Wyo.

Goose Creek below Sheridan, Wyo.

Clear Creek above Kumor Draw, near Buffalo, Wyo.

Belle Fourche River below Moorcroft, Wyo.

Belle Fourche River below Hulett, Wyo.

Wheatland Creek below Wheatland, Wyo.

Crow Creek near Archer, Wyo.

Blacks Fork near Lyman, Wyo.

Hams Fork near Diamondville, Wyo.

Bear River below Smiths Fork, near Cokeville, Wyo.

Salt River above reservoir near Etna, Wyo.

Table 1. Fecal coliform bacteria sampling sites in Wyoming during 2000

Site no.

(fig. 1)

USGS

station no. Station name Latitude Longitude

43°44¢102

44°23¢002

44°09¢202

44°44¢352

44°48¢102

44°49¢252

44°23¢212

44°19¢192

44°42¢042

42°05¢052

41°07¢352

41°27¢082

41°45¢062

42°07¢342

43°04¢472

44°45¢132

42°59¢512

42°51¢592 108°41¢042

106°57¢102

107°07¢452

106°57¢402

106°37¢232

104°56¢242

104°35¢072

104°57¢022

104°39¢042

110°10¢202

110°31¢572

110°58¢232

111°02¢122

108°22¢292

108°09¢382

108°02¢082

108°52¢352

108°35¢292
on the 303(d) list for 2000 for fecal coliform. The State of the larger statewide monitoring network, the constituents 

Wyoming water-quality criterion for fecal coliform to be monitored at each site are selected to provide basic 

bacteria for a water body is not a single number; the statewide water-quality data and to monitor possible 

criterion depends on the class of water, time of year, and water-quality concerns at that site, as determined by landlocation relative to sewage-treatment-plant outfalls use information and historical water-quality records. Of 

(Wyoming Department of Environmental Quality, 1990). the 18 sites being monitored for bacteria, 9 are included on 

The criterion of 400 cols/100 mL applies to most surface the 303(d) list for 2000 with fecal coliform listed as the 

waters in the State during May through September. For impairment for contact recreation uses: Bighorn River at 

this report, 400 cols/100 mL of fecal coliform is used for Basin, Wyo.; Bitter Creek near Garland, Wyo.; Big Goose 

consistency across sites and sampling periods. Creek above Park Creek near Sheridan, Wyo.; Little Goose 

Creek near Sheridan, Wyo.; Goose Creek below Sheridan, 

Wyo.; Belle Fourche River below Moorcroft, Wyo.; Belle 

Fourche River below Hulett, Wyo.; Crow Creek near 

Archer, Wyo., and Blacks Fork near Lyman, Wyo. During water year 2000, the USGS is collecting water Wheatland Creek below Wheatland, Wyo., is listed on the samples for analysis of fecal coliform bacteria at 18 sites 303(d) list as well, but has ammonia identified as the that are part of the statewide WDEQ monitoring network primary impairment. A less restrictive criterion applies to (fig. 1). Samples are collected on a quarterly basis this reach of Wheatland Creek because of its close proxim- (October-December, January-March, April-June, and July- ity to a sewage-treatment-plant outfall. September) under varying hydrologic conditions. Within 

3

FECAL COLIFORM MONITORING

CROOK PARK

BIG

HORN

SHERIDAN

WASHAKIE

JOHNSON

CAMPBELL

TETON

HOT

SPRINGS

FREMONT

LINCOLN

UINTA

SWEETWATER

NATRONA

CONVERSE

NIOBRARA

WESTON

GOSHEN

PLATTE

ALBANY

CARBON

LARAMIE

SUBLETTE

1

2

3

4

5

6

7

8

10 11

12

13

14

14

15

16

17

18

9

Jackson

 Lake

Fontenelle

 Reservoir

Flaming

Gorge

Reservoir

Seminoe

Reservoir

Pathfinder

Reservoir

Boysen

Reservoir

Glendo

Reservoir

Snake

River

Bighorn

Greybull

River

Rive

Wind

r

River

Green

River

Sweetwater

River

Powder

R vi er

Belle

Fourche

River

North

Platte

River

Crow

Creek

N

Platte

River

Laramie

River

Bighorn

Lake

Yellowstone

 Lake

Figure 1. Location of sampling sites in Wyoming.

111°

110°

109° 108° 107° 106° 105° 104°

44°

43°

42°

41°

45°

Yellowstone

National

Park

Cheyenne

Riverton

Casper

0

0

50

50

100 MILES

100 KILOMETERS Sampling site and number

EXPLANATION
summary. Non-ideal colony 

counts occur when bacteria 

growth outside the ideal range 

of 20-60 colonies occurs on a 

single plate. Time-series 

scatter plots of the data are 

shown for eight of the nine 

sites identified on the 303(d) 

list (fig. 2). Big Goose Creek

(site 7) is not included because

of the small sample size (n=2)

from the current sampling

location.

Fecal coliform concentrations did not exceed the waterquality criterion of 400 

cols/100 mL in 83 percent of 

all samples collected. For all 

sites, minimum and median 

fecal coliform concentrations 

were less than 400 cols/100 

mL. At least one sample at 14 

of the 18 sites, however, did 

exceed 400 cols/100 mL 

during 1990-99. The four sites 

that had no samples exceeding 

this criterion are on the Popo 

Agie River (site 1), the 

Greybull River (site 5), the 

Hams Fork (site 16), and the 

Bear River (site 17).

Fecal coliform concentrations at Goose Creek below 

Sheridan, Wyo., (site 9) 

exceeded the water-quality 

criterion in 35 percent of the 

samples. The highest median 

concentration for all the sites (320 cols/100 mL) was at 

Goose Creek. Fecal coliform exceeded the water-quality 

Summary statistics of fecal coliform concentrations are criterion in 35 percent of the samples from Wheatland 

presented for the 18 sites currently being monitored for Creek (site 13), and the highest maximum fecal coliform 

fecal coliform (table 2). The median was selected as a concentration from all streams (45,000 cols/100 mL) 

measure of the central tendency of the data to minimize the occurred in a sample from that site. High fecal coliform 

effects of outliers. The period of record summarized for concentrations of 14,000 and 17,000 cols/100 mL were 

this report is from 1990 to 1999. For some sites, only a found in samples from sites on the Belle Fourche River 

partial period of record was available, and sampling below Moorcroft, Wyo. (site 11), and below Hulett, Wyo. 

frequency may have been variable between years. A (site 12), respectively. All four of these sampling sites 

median concentration was not calculated for Big Goose occur below mixed urban and agricultural areas.

Creek (site 7) because only two samples have been 

collected by the USGS from the current sampling location The Bighorn River, Goose Creek, and the Belle 

established in May 1999. Prior to May 1999, samples on Fourche River have upstream and downstream sites that 

Big Goose Creek were collected about 4 miles upstream can be compared for spatial changes in the basin. The 

from the present sampling site. Because inflows from median concentrations of fecal coliform varied on the 

tributaries in between the sites may contribute fecal Bighorn River from 87 cols/100 mL at the upstream site at 

coliform, the data for the two sites were not combined. Lucerne (site 3) to 120 cols/100 mL at the downstream site 

For all sites, fecal coliform concentrations from analyses at Basin (site 4). The maximum concentration at Lucerne 

with non-ideal colony counts are included in the statistical (3,200 cols/100 mL) was much lower than the maximum 

 

 

 

 

4

FECAL COLIFORM RESULTS

06232600

06235500

06264700

06274300*

06276500

06284500*

06302000*

06304500*

06305500*

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

1990-1999 (28)

1990-1999 (40)

1990-1999 (41)

1990-1999 (41)

1996-1999 (16)

1993-1999 (29)

1999 (2)

1990-1999 (40)

1990-1999 (40)

1993-1999 (28)

1990-1999 (37)

1993-1999 (28)

1990-1999 (40)

1991-1999 (36)

1996-1999 (16)

1993-1999 (28)

1993-1998 (28)

1990-1999 (20)

<1

1

6

1

2

2

22

1

1

2

<1

3

8

9

3

<1

<1

<1

32

65

87

120

21

140

--

62

320

44

200

51

170

140

88

28

21

15

400

2,600

3,200

8,900

390

1,100

1,000

860

8,500

500

14,000

17,000

45,000

6,800

9,000

220

340

500

0

15

7

20

0

21

--

15

35

14

30

21

35

17

19

0

0

5

06320210

06426500*

06428050*

06669050

06756060*

09222000*

09224050

10038000

13027500

USGS

station no.

Site no.

(fig. 1)

Period

of record

(no. of samples)

Percent

Minimum Median exceedence

Fecal coliform concentrations

Maximum

Table 2. Summary statistics for fecal coliform concentrations for sampling sites on

Wyoming streams, 1990-1999

[Fecal coliform concentrations in colonies per 100 milliliters; * indicates site is included on the 303(d) list for

2000 for fecal coliform impairment; percent exceedence is the percent of samples at that site exceeding

400 colonies per 100 milliliters.]
concentration at Basin (8,900 cols/100 mL). Most of the 51 cols/100 mL) than at the upstream site (site 11, 200 

land use in Bighorn River Basin is agricultural and cols/100 mL). In contrast, the maximum concentration 

rangeland, with small, dispersed urban areas (Zelt and was greater at the downstream site (17,000 cols/100 mL) 

others, 1999). In the Goose Creek watershed, the elevated than at the upstream site (14,000 cols/100 mL).

median fecal coliform concentration (320 cols/100 mL) in 

samples from Goose Creek (site 9) may result from its Boxplots are presented to show the al variations

location downstream of the Sheridan, Wyo., urban area. in fecal coliform concentrations and stream discharge at

The median concentration was lower (62 cols/100 mL) in eight of the nine stations identified on the 303(d) list 

samples from Little Goose Creek (site 8) which flows (fig. 3). Individual sample points are shown instead of

through part of the urban area as well. Concentrations of boxes where the number of samples is less than nine.

fecal coliform in Big Goose Creek (site 7) indicate bacteria Some general patterns are discernible in the fecal coliform

were present upstream from the urban area as well. Mixed data from different sites. At all sites except Goose Creek

land use occurs upstream from the Big Goose Creek site, (site 9), the maximum fecal coliform concentration

including agricultural, rangeland, and rural domestic. On occurred during April-June or July-September. The high

the Belle Fourche River, the median fecal coliform concentrations during April-June on the Bighorn River

concentration was lower at the downstream site (site 12, (site 4), Bitter Creek (site 6), the Belle Fourche River 

 tempor

 

 

 

 

 

 

 

 

 

 

5

Water-quality criterion

Sample

EXPLANATION

1

1

100,000

100,000

2

2

5

5

10

10

20

20

50

50

100

100

200

200

500

500

1,000

1,000

2,000

2,000

5,000

5,000

10,000

10,000

20,000

20,000

50,000

50,000

100,000 100,000

100,000

100,000

100,000

100,000

1 1

1

1

1

1

2 2

2

2

2

2

5 5

5

5

5

5

10 10

10

10

10

10

20 20

20

20

20

20

50 50

50

50

50

50

100 100

100

100

100

100

200 200

200

200

200

200

500 500

500

500

500

500

1,000 1,000

1,000

1,000

1,000

1,000

2,000 2,000

2,000

2,000

2,000

2,000

5,000 5,000

5,000

5,000

5,000

5,000

10,000 10,000

10,000

10,000

10,000

10,000

20,000 20,000

20,000

20,000

20,000

20,000

50,000 50,000

50,000

50,000

50,000

50,000

FE

C

AL C

OLIFO

R

M

C

O

N

C

E

N

T

R

ATIO

N, IN

C

OLO

NIE

S

P

E

R 100 MILLILIT

E

R

S

WATER YEAR WATER YEAR

WATER YEAR

Figure 2. Fecal coliform concentrations for selected Wyoming streams, 1990-99.

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

1990 1992 1994 1996 1998

SITE 4 (Station No. 06274300)

SITE 9 (Station No. 06305500)

SITE 14 (Station No. 06756060)

SITE 6 (Station No. 06284500)

SITE 11 (Station No. 06426500)

SITE 15 (Station No. 09222000)

SITE 8 (Station No. 06304500)

SITE 12 (Station No. 06428050)
(sites 11 and 12), and Crow Creek (site 14) coincide with bacteria in sediment may be longer than 30 days, comthe period of increased discharge. Fecal coliform concen- pared to die-off rates of several days in the water column 

trations generally show positive correlations with dis- (Sherer and others, 1992). In addition to transport procharge because surface runoff from pastures, feedlots, and cesses and variable survival rates, land-use activity, such 

urban areas can contribute sediment and associated fecal as cattle grazing and outdoor recreational activities, 

coliform to streams (Smith and others, 1993, Wilhelm and generally increase during spring and summer months as 

Maluk, 1998). Increased discharge can also resuspend fine well. The elevated concentrations and sources coincide 

bottom sediments. Bacteria can survive in the protective with the time period when public-health risk is also higher 

environment of bottom sediment, particularly those with at because contact recreation potentially is occurring during 

least 25 percent clay (S. Embrey, 1991). Survival rates of warmer months. However, most of the health risk studies 

6

(10)

(11)

(10)

(10)

(10) (11)

(10)

(9)

(7)

(8)

(7)

(7)

(8)

(6) (7)

(7)

(9)

(9)

(9)

(9)

(4)

(4)

(4)

(4)

(10)

(10)

(9)

(11)

(10)

(10)

(9)

(8)

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

0.1

100,000

0.2

0.5

1

2

5

10

20

50

100

200

500

1,000

2,000

5,000

10,000

20,000

50,000

Data value

Data value

75th percentile

75th percentile

Median

Median

25th percentile

25th percentile

10th percentile

10th percentile

90th percentile

90th percentile

Fecal Concentration

Discharge

Number in parentheses

is number of samples.

EXPLANATION

FE

C

AL C

OLIFO

R

M

C

O

N

C

E

N

T

R

ATIO

N, IN

C

OLO

NIE

S

P

E

R 100 MILLILIT

E

R

S

S

T

R

E

A

M

DIS

C

H

A

R

G

E, IN

C

U

BIC FE

E

T

P

E

R

S

E

C

O

N

D

SAMPLING PERIOD SAMPLING PERIOD

SAMPLING PERIOD

Figure 3. Temporal variations in fecal coliform concentrations and discharge for selected Wyoming streams.

Oct-Dec Jan-Mar Apr-Jun July-Sep Oct-Dec Jan-Mar Apr-Jun July-Sep

Oct-Dec Jan-Mar Apr-Jun July-Sep

Oct-Dec Jan-Mar Apr-Jun July-Sep

Oct-Dec Jan-Mar Apr-Jun July-Sep

Oct-Dec Jan-Mar Apr-Jun July-Sep Oct-Dec Jan-Mar Apr-Jun July-Sep

Oct-Dec Jan-Mar Apr-Jun July-Sep

SITE 4 (Station No. 06274300)

SITE 9 (Station No. 06305500)

SITE 14 (Station No. 06756060)

SITE 6 (Station No. 06284500)

SITE 11 (Station No. 06426500)

SITE 15 (Station No. 09222000)

SITE 8 (Station No. 06304500)

SITE 12 (Station No. 06428050)
have focused on swimming-associated illness. While full conductance, pH, 

contact swimming does occur in some Wyoming streams, and dissolved 

recreational contact is generally more passive in the form oxygen generally 

of canoeing, rafting, and fishing. were negatively 

correlated with 

The highest fecal coliform concentration in samples fecal coliform. 

collected from Goose Creek below Sheridan, Wyo. (site 9), The correlation 

occurred during October-December. However, this with discharge 

concentration is outside the range that is typical for that was statistically 

time period. The highest median concentration at Goose significant for 

Creek occurred during January-March. Although fecal three sites: the 

coliform concentrations were generally lower during the Bighorn River 

summer months on Goose Creek, the concentrations in (site 4), Bitter 

some summer samples were higher than 400 cols/100 mL. Creek (site 6) and 

These fecal coliform data indicate the need for monitoring Blacks Fork (site 

streams for fecal coliform throughout the year to account 15). Specific 

for varying hydrologic conditions and levels and types of conductance, 

land and water use. which generally is 

inversely correEnvironmental conditions can affect the survival rate of lated with 

bacteria once they leave the digestive tract of warm- discharge, also 

blooded animals. Spearman's rank correlation procedure had significant 

was used to determine the relation between various water- negative correlations with fecal coliform at the Bighorn 

quality field measurements during sample collection. The River (site 4) and Bitter Creek (site 6) sites. A positive 

procedure provides a measure of the intensity of associa- correlation between fecal coliform and water temperature 

tion between two variables. The correlation coefficient, was statistically significant at all sites, except Goose Creek 

rho, is computed using ranks of the data rather than actual (site 9). A negative correlation between fecal coliform and 

data values (Helsel and Hirsh, 1995). Rho values range dissolved oxygen was statistically significant at all sites, 

between 1 and +1; a negative value indicates an inverse except Goose Creek (site 9). The correlations with disrelation between the data ranks. Correlation coefficients solved oxygen generally were stronger than the correlabetween fecal coliform concentrations and selected water- tions with temperature for these sites.

quality field measurements for eight sites are shown in 

table 3. Spearman correlation coefficients were considered 

statistically significant where p-values were less than 0.05. 

Discharge and water temperature were positively corre- Analyses for fecal coliform indicator bacteria are an lated with fecal coliform concentrations, whereas specific easy, inexpensive method for determining the potential 

presence of other pathogens. 

However, more detailed information would be beneficial on 

the nature of the fecal contamination in selected Wyoming 

streams. Specific types of 

fecal coliform bacteria, like 

Escherichia coli (E. coli), are 

more closely linked with 

swimming-associated gastrointestinal illness than the more 

general fecal coliform analyzed in this study (Dufour, 

1984). As a result of freshwater beach studies, the U.S. 

Environmental Protection 

Agency recommended the use 

of E. coli or enterococci as 

better indicators for State 

water-quality criteria (U.S. 

Environmental Protection 

Agency, 1986). Methods for 

7

ADDITIONAL MONITORING

06274300

06284500

06304500

06305500

06426500

06428050

06756060

09222000

4

6

8

9

11

12

14

15

0.495

0.775

0.266

0.021

0.309

0.331

0.287

0.696

-0.545

-0.843

-0.079

0.012

-0.123

-0.350

-0.397

-0.494

-0.498

-0.556

-0.237

-0.066

-0.166

-0.249

0.034

-0.403

0.713

0.549

0.605

0.019

0.551

0.420

0.425

0.572

-0.776

-0.634

-0.735

-0.214

-0.581

-0.692

-0.342

-0.684

USGS

station no.

Site no.

(fig. 1) Discharge

Dissolved

oxygen

Specific

conductance pH

Water

temperature

Table 3. Spearman rank correlation coefficients between fecal coliform and water-quality

field measurements for selected Wyoming streams

[Italicized numbers indicate a significant relation where p-values were less than 0.05]
direct analysis for pathogens generally are expensive and (S. Parveen, University of Florida, written commun., 

sampling procedures can be complicated; however, these 2000). Additional monitoring using other indicators or 

methods are evolving. Techniques for differentiating direct analysis of pathogens may help to better define the 

sources of fecal contamination also are evolving, including occurrence and sources of pathogenic contamination in 

multiple antibiotic resistance and ribotype profiles Wyoming's streams. 

U.S. Environmental Protection Agency, 1976, Quality 

criteria for water: Washington, D.C., U.S. 

Environmental Protection Agency, 256 p.

____1986, Ambient water quality criteria for bacteria1986: U.S. Environmental Protection Agency, 

440/5-84-002, 18 p.

Wilhelm, L.J., and Maluk, T.L., 1998, Fecal-indicator 

bacteria in surface waters of the Santee River Basin 

and coastal drainages, North and South Carolina, 

1995-98: U.S. Geological Survey Fact Sheet 

FS-085-98, 6 p.

Wyoming Department of Environmental Quality, 1990, 

Water quality rules and regulations: Quality 

standards for Wyoming surface waters: Wyoming 

Department of Environmental Quality, Water 

Quality Division, Chap. I, 87 p.

____2000, 2000 305(b) Water quality assessment: 

Wyoming Department of Environmental Quality, 

Water Quality Division, [variously paged].

Zelt, R.B., Boughton, G.K., Miller, K.A., Mason, J.P., and 

Gianakos, L.M., 1999, Environmental setting of the 

Yellowstone River Basin, Montana, North Dakota, 

and Wyoming: U.S. Geological Survey WaterResources Investigations Report 98-4269, 112 p.

Dufour, A.P., 1984, Health effects criteria for fresh 

recreational waters, Cincinnati, Ohio, U.S. 

Environmental Protection Agency, 

EPA-600/1-84-004, 33 p.

Embrey, S.S., 1992, Surface-water-quality assessment of 

the Yakima River Basin, Washington: Areal 

distribution of fecal indicator bacteria, July, 1988: 

U.S. Geological Survey Open-File Report 91-4073, 

34 p.

Helsel, D.R., and Hirsh, R.M., 1995, Statistical methods in

water resources: New York, Elsevier Science

Publishing Company, Inc., 529 p.

Myers, D.M., and Sylvester, M.A., 1997, National field 

manual for the collection of water-quality data, 

biological indicators: U.S. Geological Survey 

Techniques of Water-Resources Investigations, 

book 9, chapter A7, 49 p.

Sherer, B.M., Miner, J.R., Moore, J.A., and Buckhouse, 

J.C., 1992, Indicator bacteria survival in stream 

sediments, Journal of Environmental Quality, v. 21, 

p. 591-595.

Smith, R.A., Alexander, R.B., and Lanfear, K.J., 1993, 

Stream water quality in the conter-minous United 

States-status of trends of selected indicators during 

the 1980's, in National Water Summary 1990-91, 

Hydrologic events and stream water quality: U.S. 

Geological Survey Water-Supply Paper 2400, p. 

111-140.

 

 

 

For copies of this report or additional information,

contact:

District Chief

U.S. Geological Survey, WRD

2617 E. Lincolnway, Suite B

Cheyenne, Wyoming 82001-5662

Email: state_rep_wy@usgs.gov

Internet: http://wy.water.usgs.gov/

Printed on recycled paper

REFERENCES

8