WYOMING DEPARTMENT OF ENVIRONMENTAL QUALITY WATER QUALITY DIVISION BENEFICIAL USE RECONNAISSANCE PROGRAM MONITORING AND ASSESSMENT REPORT

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1 WYOMING DEPARTMENT OF ENVIRONMENTAL QUALITY WATER QUALITY DIVISION BENEFICIAL USE RECONNAISSANCE PROGRAM MONITORING AND ASSESSMENT REPORT Waterbody: Watershed: Prairie Dog Creek Tongue 8-digit HUC: Segment Assessed: Class: 2AB (b) Report and 303 (d) List: Listed as only partially supporting aquatic life use. Author: Scott Collyard INTRODUCTION Prairie Dog Creek originates in the Bighorn Mountains near Moncreiffe Ridge, northwest of Story, Wyoming. The stream flows east until the confluence with Jenks Creek, where it turns north until it enters the Tongue River near the Montana border. Tributaries to the assessed segment of Prairie Dog Creek segment include Jenks Creek, Murphy Gulch, Buffalo Run Creek, Meade Creek, and Wildcat Creek. Stream flow in Jenks and Meade Creek is augmented during the irrigation season by a trans-basin diversion from the Piney Creek drainage and has a significant influence on flow in Prairie Dog Creek. Classification Prairie Dog Creek is classified by the Wyoming Surface Water Classification List as a Class 2AB, cold water stream (WDEQ/WQD, 2001b). According to Wyoming Water Quality Rules and Regulations, Chapter 1, Class 2AB waters are those known to support game fish polulations or spawning and nursery areas at least seasonally. Unless it is shown otherwise, these waters are presumed to have sufficient water quality and quantity to support drinking water supplies and are protected for that use. Class 2AB waters are also protected for nongame fisheries, fish consumption, aquatic life other that fish, primary contact recreation, wildlife, industry, agriculture and scenic value uses. REPORT OBJECTIVE Prairie Dog Creek was included on the (d) list of impaired waterbodies because anecdotal data suggested that the stream was only partially supporting aquatic life use. Recognizing the repercussions of such a listing, Prairie Dog Creek was later removed from the 1

2 impaired waters list and placed on a separate list of waters needing credible assessment data before impairment status could be determined. Originally, suspected causes of impairment were siltation, nutrients, salinity/tds/chlorides, flow alteration, and habitat degradation. The suspected sources of impairment included range land, irrigated cropland, pasture land, channelization, flow alteration, streambank alteration, and removal of riparian vegetation. The purpose of this report is to document the DEQ assessment data and provide a determination of whether the designated uses of Prairie Dog Creek are supported In , EnTech, Inc, under contract with the Wyoming Water Development Commission, conducted a Level I study of the Prairie Dog Creek watershed (EnTech, 2001). As part of this study, water quality data was collected at 11 locations within the watershed. These water quality data will be used in conjunction with WDEQ data to determine use support status. METHODS AND MATERIALS All collection, analysis, and evaluation of Prairie Dog Creek was conducted in accordance with approved assessment procedures as outlined in the following documents: 1) Manual of Standard Operating Procedures for Sample Collection and Analysis (WDEQ/WQD, 2001). 2) Quality Assurance Project Plan (QAPP) for Beneficial Use Reconnaissance Project (BURP) Water Quality Monitoring (WDEQ/WQD, 2001a). 3) A bioassessment method for use in Wyoming stream and river water quality monitoring (King, 1993). 4) Beneficial use reconnaissance project-wadeable stream monitoring methodology (WDEQ/WQD, 1998). 5) Wyoming s method for determining water quality condition of surface waters (WDEQ/WQD, 2002). ASSESSMENT STATIONS Nine assessment stations were established on Prairie Dog Creek and one station was established on each of four tributaries (Table 1). In most cases, stations were selected upstream and downstream of each of the four targeted tributaries, as well as on the tributary itself. Two of the tributary stations (Murphy Gulch and Wildcat Creek) were limited to water samples only. PHYSICAL SETTING Prairie Dog Creek Prairie Dog Creek originates in the transition between the Middle Rockies Central (MRC) and Northwestern Great Plains (NGP) ecoregions (Omernik and Gallant, 1987), with the majority of 2

3 stream miles flowing through the NGP. The uppermost station, PD-1, is assessed an NGP station although it lies on the transition from the mountains to the plains and may display some characteristics of a montane stream. All stations downstream of PD-1 clearly are in the NGP ecoregion. Prairie Dog Creek is utilized extensively for irrigation. Its headwaters lie at a small spring producing less than one cubic foot per second (cfs) of flow. Natural streamflow is augmented during the irrigation season by trans-basin diversions from the Piney Creek drainage to Jenks and Meade Creek and then into Prairie Dog Creek. Upon receiving this influx of irrigation water, Prairie Dog Creek can flow as high as cfs during irrigation season (EnTech 2001). In October, the trans-basin diversion of water is ceased, resulting in greatly decreased streamflow until the irrigation season begins in May. Although the most upstream reaches of Prairie Dog Creek were not included in the WDEQ assessment, they have been considerably altered by irrigation water diversion systems and could have negative impact on Prairie Dog Creek. In particular, the trans-basin diversions have caused considerable erosion to the Jenks Creek and Meade Creek drainage below their respective drop structures near Tunnel Hill in Story. More detailed descriptions of the aforementioned diversion systems, including photos, can be found in the EnTech final report (EnTech, 2001). Specific station characteristics such as land use, geology, soils, and channel type varied throughout the watershed. See Table 3 for these characteristics, as well as for drainage area and discharge data. Photos were taken at all of the WDEQ stations, including upstream, downstream, panoramics of the area around each station, and other descriptive photos. Representative photos can be found in the Appendix B. RESULTS AND DISCUSSION WDEQ water quality sampling results from the October sampling are presented in Table 4. WDEQ water quality sampling results from the November sampling are presented in Table 5. Please note that EnTech sampled a short list of parameters during the first five sampling events, with a more extensive list utilized during the last two sampling events. Only significant results are discussed below; parameters not discussed below either did not vary from values expected to be found in the presence of minimal human influence, were within State water quality standards, or did not have values considered to have negative affects on aquatic life (EnTech 2001). Water Quality Temperature WDEQ data showed each station to be below the WDEQ/WQD (2001c) standard of 20 o C for a 3

4 cold water fishery. However, the mid to late fall sampling dates were not conducive to detection of violations of the temperature standard. The EnTech data showed water temperature approaching or exceeding the temperature standard at the lower five stations during their June and August sampling events, suggesting that the lower reaches of Prairie Dog Creek may not fully-support the protection and propagation of cold water fish species (EnTech 2001). Turbidity and Total Suspended Solids WDEQ data showed that October turbidity and total suspended solids (TSS) concentrations were high at the most downstream stations (Table 4 and Table 5). In November, turdidity and TSS had decreased significantly. Although it is not unusual for turbidity and TSS concentrations of a stream to increase somewhat in a downstream direction, the increase in these parameters from PD-7 to PD-8 are of greatest concern. In October, turbidity increased more than 17 NTU from PD-7 to PD-8, reaching 23 NTU at PD-8. An increase of 10 ntu or more than can be attributed to anthropogenic activities is a violation of Wyoming water quality standards (WDEQ/WQD, 2001c). TSS exceeded 100 mg/l at PD-8 and PD-9. EnTech data showed greater extremes for turbidity and TSS than did DEQ data (EnTech 2001). Turbidity readings of NTU were recorded at below Dutch Creek, below Coutant Creek, and above the Tongue River in October of In June of 2001, turbidity exceeded 20 NTU from Jenks Creek downstream, with turbidity readings exceeding 100 NTU at four of five sites downstream of Meade Creek. Turbidity and TSS exceeded levels considered detrimental to fish and other aquatic life. Lloyd (1987) stated that turbidity as low as mg/l and TSS concentrations greater than 35 mg/l can negatively affect fish communities. Newcombe and Jensen (1996) states that TSS greater than 18 mg/l can affect fish feeding behavior and abundance, and TSS greater than 50 mg/l can result in reduced rates of weight gain and affect avoidance behavior of adult rainbow and cutthroat trout. PD 8 and PD-9 clearly exceeded the thresholds suggested by Lloyd (1987) and Newcombe and Jensen (1996), suggesting impairment of the cold water fishery designated use. Electrical Conductivity and Total Dissolved Solids Electrical conductivity (EC) and Total Dissolved Solids (TDS) increased in a downstream direction during both DEQ sampling events (Table 4 and Table 5) and each EnTech sampling event (EnTech 2001). One exception was an unusually high EC at EnTech s above Hwy 87 station in June. The trend of increasing EC reflects an increase in dissolved constituents in a downstream direction. Although no numeric EC or TDS standards exist for Wyoming streams, an EC of between 700 to 3000 us/cm can limit suitability of water for agricultural uses. For the October DEQ data, EC slightly exceeded 700 at PD-8 and PD-9, and approached 2000 in WC-1. DEQ data indicated that for all stations except PD-1, EC was higher in November than in October, reflecting the end of flow diversion from North Piney Creek. In November, EC 4

5 exceeded 700 at all stations downstream of PD-4 and exceeded 2000 at WC-1. North Piney Creek drains a primarily granitic watershed with few sources of dissolved constituents, whereas Prairie Dog Creek and the sampled tributaries drain watersheds with largely sedimentary geology. Thus, it appears that the water diverted from North Piney Creek increases the suitability of Prairie Dog Creek water for irrigation, although Prairie Dog Creek would not be able to support nearly as much irrigation without the North Piney Creek diversion. Sulfate Sulfate concentrations increased steadily downstream in both October and November, with higher concentrations being observed in November (Table 4 and Table 5). This follows the same trend as was observed for EC and TDS. The EnTech data showed concentrations as high as 865 mg/l (EnTech 2001). Wildcat Creek appears to be a significant source of sulfate during both the irrigation and non-irrigation seasons, although, in November, elevated sulfate concentrations are observed upstream of Wildcat Creek. Although Wyoming does not have a numeric surface water standard for sulfate, Winget and Mangum (1979) suggest that concentrations above 150 mg/l may have negative effects on aquatic life. Chapter 8 of WDEQ Water Quality Rules and Regulations limits sulfate to less than 250, 200, and 3000 mg/l for groundwater to be used for domestic, agricultural, and livestock purposes, respectively (WDEQ 2001d). It can be implied that these limits for groundwater would also be appropriate for surface water being used for similar purposes. The domestic and agricultural criteria were not exceeded at any of the sampled locations in October, but was exceeded at PD-8 and PD-9 in November. The U.S. Environmental Protection Agency (EPA) does not have a maximum contaminant level for sulfate in drinking water, but does have a maximum contaminant goal of 500 mg/l. This goal was not exceeded at any station except WC-1. Sulfate is a natural component of surface waters, and generally increases in concentration as streams flow from its headwaters to its mouth through the NGP ecoregion. However, sulfate concentrations can be increased by irrigation returns and industrial and other point-source discharges. The presence of higher sulfate concentrations in November indicate that much of the sulfate in Prairie Dog Creek is from sources other than irrigation returns, and could be from other man-induced factors or from natural sources. Nevertheless, the high concentrations of sulfate in Wildcat Creek are clearly affecting Prairie Dog Creek water quality, whether from natural or anthropogenic origin. Hardness, Total Alkalinity, Bicarbonate, and Sodium Absorption Ratio (SAR) Hardness and alkalinity increased in a downstream direction, with higher values being found in November (Table 4 and Table 5). There are no standards for hardness or alkalinity in Wyoming, however, hardness in excess of total alkalinity is considered excess and is indicative of the 5

6 presence of divalent metals, such as iron, strontium, and manganese. The EnTech data showed total iron concentrations exceeding 2.0 mg/l (EnTech 2001). EnTech alkalinity, bicarbonate, and the sodium absorption ratio (SAR) data showed the same trend as the WDEQ data, although SAR remained low (EnTech 2001). Each parameter increased in a downstream direction, with bicarbonate concentrations exceeding 300 mg/l at the most downstream stations. When bicarbonate concentrations are high, calcium and magnesium ions precipitate as carbonates in the soil water as the water becomes more concentrated through evaporation and transpiration. As a result, the ratio of sodium to calcium and magnesium increases (increasing SAR), possibly resulting in soil and plant damage (USEPA, 1986). Therefore, the low SAR of Prairie Dog Creek water may not be a true representation of irrigation suitability over the long-term. Continued application of Prairie Dog Creek water could result in decreased crop production over time due to the elevated bicarbonate concentrations. Fecal Coliform Fecal coliform samples collected by EnTech (EnTech 2001) from 10/11/2000 to 8/16/2001 showed numerous samples from the mid to lower reaches of Prairie Dog Creek that exceeded 200 colonies per 100 ml, with several exceeding 400 colonies per 100 ml (Table 13). These samples indicate that fecal coliform is present in quantities that threaten the use of Prairie Dog Creek for primary contact recreation at certain times of the year, and that impairment of the use of Prairie Dog Creek for contact recreation may exist. In response to these results, WDEQ sampled E. coli bacteria at 6 sites along Prairie Dog Creek (Figure 2) from 7/9/2003 to 7/17/2003. E. coli results and site descriptions are presented in tables 14 and 15 respectively. The 5-sample, 30-day geometric mean value for all sites on Prairie Dog Creek exceeded the EPA recommended Water Quality Standard for E. coli of 126 organisms per 100 ml. E. coli was lowest at the most upstream site and increased downstream to EC-3 before steadily decreasing at remaining downstream sites. This pattern may be related to land use activity. Primary land use in the upper Prairie Dog Creek drainage is livestock grazing whereas Primary land use on the lower Prairie Dog Creek drainage is irrigated hayland. Date is presented in table C. Habitat Quality Riffle Substrate Composition and Silt Cover Riffle substrate composition varied among the Prairie Dog Creek assessment stations. Gravel (coarse + fine) was the dominant riffle substrate component at PD-1, PD-3, PD-4, PD-5, and PD- 6. Cobble was dominant at PD-2 and PD-7, as well as the tributary stations JC-1 and MC-1. Jenks and Meade Creek appeared to contribute little sand or silt to substrate composition immediately below the confluences despite the high degree of bank failure found on these creeks (EnTech 2001). Sand was dominant at PD-8 and PD-9, which were the most downstream assessment stations on PDC (Table 6). Prairie Dog Creek becomes a sand dominated stream between PD-7 and its confluence with the Tongue River. It is believed that the sand dominated 6

7 stream bed below PD-7 is largely due to the alterations in the natural flow regime, streambed mobility, and channel morphology and is a result of irrigation diversions and returns. Alterations in any of the above parameters could result in an increased width to depth ratio and lower stream gradient and could result in increased deposition through a loss in stream energy. It was noted that cobble and gravel was found in isolated areas underneath the sand-dominated substrate, suggesting the channel has become embedded with sand. Qualititative habitat assessment scores are shown in Table 7. PD-1, PD-2, and JC-1 have relatively high habitat scores. JC-1 had some instability and disruptive pressure along the left bank. Habitat scores are considerably lower at the other stations, with PD-3 and PD-4 having the lowest scores. Scores are lower at PD-3, PD-4, and PD-5 primarily due to increased silt cover on riffle substrate, a decrease in the ratio of pools to riffles (decreased geomorphic complexity), and a high width to depth ratio. The decreased geomorphic complexity and high width to depth ratio are often characteristic of streams receiving significant flow augmentation. During the irrigation season, streamflow greatly exceeds the natural capacity of the stream channel, resulting in excessive widening and straightening. At PD-8 and PD-9, the greater percentage of fine substrate materials lowered the total score, although other habitat parameters scored fairly well. Macroinvertebrates and Biological Condition Biometrics developed by Jessup and Stribling (2002) were utilized as a tool to assess biotic/ecological integrity of Prairie Dog Creek as a means of determining whether designated uses, such as aquatic life, are attained. Prairie Dog Creek was evaluated with the Wyoming Stream Integrity Index (WSII) developed for the Northwestern Great Plains ecoregion (Jessup and Stribling 2002). According to Jessup and Stribling (2002), streams that receive WSII scores that rate at or above the 25 th percentiles of reference conditions are rated as good or very good by the WSII and are deemed supportive of aquatic life uses (Table 1). Narrative rating of WSII scores indicate that the biological condition of Prairie Dog Creek was good. JC-1 and MC-1 were narratively assessed as good and fair, respectively (Table 8). These data suggest that aquatic life use (other than fish) is fully-supported by Prairie Dog Creek. Examination of individual WSII metrics (Table 8) as well as supplemental metrics (Table 9) indicate that Prairie Dog Creek is affected by anthropogenic activities, although overall the stream appears to fully-supporting aquatic life uses. Percent dominant taxa is a measure of the extent the single most common macroinvertebrate taxa has in the sample. Like percent 10 dominants, the percent dominant taxa is an indicator of community balance. Additionally, the nature of the dominant taxa may also give some additional insight into the overall water quality at the station. The dominant taxa at the most upstream station (Above Jenks Creek) was riffle beatle Optioservus. Species of this taxa are generally scrapers or collector - gatherers in erosional or depositional (sediment and detritus) stream systems (Merritt and Cummins, 1996). The dominant taxa in Jenks Creek and also in Prairie 7

8 Dog Creek below Jenks Creek was the caddisfly Culoptila. Species of this taxa are scrapers are widespread in distribution and commonly found in erosional stream systems (Merritt and Cummins, 1996). The dominant taxa in Prairie Dog Creek above Murphy Gulch was the caddisfly Brachycentrus occidentalis. This species is a collector - filterer that clings to vascular hydrophytes, logs, or branches in erosional stream systems (Merritt and Cummins, 1996). The dominant taxa at the next five downstream locations (below Murphy Gulch, above and below Meade Creek, Mead Creek, and below Highway 14) was the caddisfly Hydropsyche. Species of this taxa are clinging collector - filterers that are found in erosional stream systems (Merritt and Cummins, 1996). The dominant taxa in Prairie Dog Creek above Wildcat Creek was the black fly Simulium. This species of this pollution tolerant taxa are collector - filterers found in erosional stream and pond systems (Merritt and Cummins, 1996). The dominant taxa at the most downstream station (Prairie Dog Creek below Wildcat Creek) was the mayfly Baetis tricaudatus. This species is a collector - gatherer that is common in erosional and depositional stream systems and also found on vascular hydrophytes in littoral zones of lentic systems (Merritt and Cummins, 1996). The black fly Simulium was the second most common taxa at this station. These data suggest an overall decrease in water quality in Prairie Dog Creek from the upper to lower stations with the dominant taxa going from scrapers to collector - filterers to collector - gatherers. Other Historical and Ancillary Information The Wyoming Department of Environmental Quality has historical water quality information on Prairie Dog Creek and Jenks Creek that corresponds to some of the sites that were sampled in Samples were collected at PD-1, PD-2, JC-1, and PD-5. The parameters of interest are turbidity, total suspended solids (TSS), sulfates, total phosphorus, and nitrate nitrogen. Table 10 lists all of the analyzed parameters for the samples collected in The turbidity and TSS values at all four of the sampling stations are very low and suggest that these two parameters are not impairing the water quality at these locations at the time of sampling. The sulfates are relatively low at the PD-1 (17 mg/l) and PD-2 (50 mg/l) stations. The sulfate concentrations are significantly higher at JC-1 (146 mg/l) and PD-5 (186 mg/l). According to King s 1993a review, sulfate levels less than 150 mg/l were optimal for macroinvertebrates. The sulfate level is nearing the 150 mg/l optimal limit for macroinvertebrates at the JC-1 station and has exceeded this limit at the PD-5 station. The total phosphorus and Nitrate Nitrogen levels were very low at all of the stations sampled and are not a source of impairment to the stream at the sampled locations. According to these results, sulfates have historically been high within the Prairie Dog Creek Drainage. During the summer flow periods between June, 1986 and September, 1992 the United States Geological Survey collected pesticide samples from Prairie Dog Creek near the confluence with the Tongue River. These data were retrieved from the Water Resources Data System (WRDS 1998). The location of this station is well downstream of the segment of Prairie Dog Creek covered by this assessment report, however those data are of interest to the entire watershed. In general, pesticides levels were very low. Picloram (Tordon ) was the only pesticide commonly 8

9 observed above the 0.01µg/L detection level. Picloram levels in lower Prairie Dog Creek ranged from <0.01 to 0.07µg/L. Dicamba and 2-4 D were observed slightly above the detection level on a couple of occasions. The higher pesticide levels appeared to correspond to the higher flow levels in Prairie Dog Creek. Additionally, water temperature was collected during these summer sampling events. Summer water temperatures (18 samples) in lower Prairie Dog Creek ranged from 10 C to 27 C with a mean temperature of 17.4 C. Only one sample (27 C) exceeded the 20.0 C maximum allowable stream temperature standard for Class 2 cold water fisheries waterbodies. The Wyoming Game and Fish Stream and Lakes Database reports 14 fish species present in Prairie Dog Creek near the confluence with the Tongue River (Sec. 23, T.58N., R. 83W.). These species are presented in Table 11. Historically, trout have been observed in Prairie Dog Creek as far back as 1959, and are the dominant trout species found in the creek. Records show that between 1959 and 1999 brown trout were collected and identified below Jenks Creek, with an estimated density of 281 fish per mile. In 1968, brown trout were introduced above Meade Creek, with a density estimate of 420 trout per mile. In 1969, brown trout were again introduced above Meade Creek, but the estimated number of trout per mile had dropped to 215. Brown trout population estimates dropped considerably in 1970 above Meade Creek where only 22 Brown Trout per mile were observed. In 1999, 257 Brown Trout per mile were reported at the Below Highway 14 crossing on the Baccari property. Of the 257 trout collected, 117 were between one and six inches long and 70 were greater than six inches long. According to Wyoming Game and Fish Biologists, trout do not migrate during their first year and the large number of fish less than one year old (117) suggests that spawning was successful. Other common fish species found in Prairie Dog Creek include the Mountain Sucker, White Sucker, and Longnose Sucker (WGFD, 1999). Biological assessments (macroinvertebrates) were collected by the WDEQ/WQD at three Prairie Dog Creek locations in These three stations: Prairie Dog Creek above Jenks Creek; Prairie Dog Creek below Jenks Creek; and, Prairie Dog Creek above Meade Creek correspond to 1998 stations PD-1, PD-2, and PD-5, respectively. Although the direct comparison of 1992 data to the 1998 data using the Wyoming Stream Integrity Index is not truly valid because of the use of a 1000 µm mesh sampler in 1992, these data comparisons do help substantiate the results of the 1998 data (Table 12). The 1992 data would have rated out as either good or very good under the Wyoming Stream Integrity Index. There are several similar attributes between the 1992 and 1998 data, including EPT taxa numbers and the percent non-insects. Major differences between the two sample events (percent Plecoptera taxa and percent 10 dominants) may be primarily associated with mesh size where smaller organisms such as midges were not collected with the larger mesh sample, thus skewing the data toward the larger-sized taxa such as those in the Order Plecoptera. 9

10 SUMMARY AND CONCLUSIONS Classification Prairie Dog Creek is classified as a Class 2 cold water stream. This classification is supported by the Wyoming Game and Fish Stream and Lake database which identifies Brown Trout present within the assessed segment. Wyoming Game and Fish data indicates successful Brown Trout spawning. Water Quality Water quality data collected from Prairie Dog Creek on October 6, 1998 indicates an increase in turbidity of greater than 10 NTU s and corresponding increase in TSS values from PD-7 to PD-8 and PD-9 (Table 4). These increases may be the result of irrigation returns adding sediment to Prairie Dog Creek upstream of PD-8 and PD-9. Water samples collected on November 23, 1998 show low turbidities and TSS values through the assessed segment on Prairie Dog Creek. The highest turbidity and TSS values were recorded at PD-8 with values of 5.4 NTU and 18 mg/l, respectively. The lower flows throughout Prairie Dog Creek during the November 23 sampling suggest that irrigation was no longer occurring and therefore reducing the amount of flow and suspended solids entering Prairie Dog Creek. While the turbidity and TSS values decreased in November, the conductivity, total dissolved solid, sulfates, and total hardness increased throughout the drainage. The lower flows eliminated the dilution effect observed in October and concentrated the dissolved constituents in solution. Of main concern is the concentration of sulfates throughout the drainage. From PD-2 to PD-9 the levels of sulfates increased significantly in Prairie Dog Creek (Table 4). These results suggest that water quality in Prairie Dog Creek is variable, and appears to depend on the flow in the stream which is controlled by the amount of irrigation which occurs in the drainage. During the summer when irrigation is occurring, the flows in Prairie Dog Creek increase due to the additional flow provided by diverted water from North Piney Creek into Jenks Creek. The irrigation demands in the drainage have resulted in several irrigation diversions and returns which add suspended sediments to Prairie Dog Creek, increasing the overall turbidity. When irrigation is completed in the fall, the flows in Prairie Dog Creek are reduced, and the amount of suspended sediment entering the stream goes down. This results in a lower turbidity throughout the drainage. Also, the lower flows concentrate the dissolved constituents and result in higher conductivities, dissolved solids, sulfates, and total hardness values. The high turbidity and TSS values recorded at PD-8 and PD-9, as well as the 0.3 mg/l total phosphorus concentration at both stations on October 6, 1998, suggest that the addition of sediment and the increase in phosphorus may be due to irrigation returns in Prairie Dog Creek, above the Wildcat Creek confluence. Physical and Habitat Quality The habitat quality varies from the upper, to the lower stations on Prairie Dog Creek. The highest habitat scores were recorded at PD-1and PD-2 and JC-1. The lowest scores were recorded at PD- 10

11 3 and PD-4. Reasons for the drop in habitat scores throughout the remainder of the assessed segment can be attributed to increased channelization due to irrigation diversions and returns, decreases in vegetation cover and bank stability, increased sedimentation, and a reduction in available aquatic habitat. Although habitat scores throughout the assessed segment are not dramatically lower than reference conditions, they do suggest that the habitat may have been affected to some degree by the irrigation practices in the area. There is a fair amount of sedimentation in Prairie Dog Creek, potentially due to the irrigation return water adding sediment to the system. A reduction in the amount of sediment entering the system would help to provide better habitat for aquatic biota and improve the quality of water in Prairie Dog Creek. Macroinvertebrates and Biological Condition The WSII metrics indicates that the macroinvertebrate community is in Good condition, with the exception of Meade Creek ( Fair ) when compared to Wyoming Plains reference stream condition. All of the stations on Prairie Dog Creek are meeting criteria for aquatic life and appear to be supporting a healthy macroinvertebrate community. However, some of the upstream stations may be lacking in community balance as indicated by the high percent 10-dominant values recorded. This result was supported by additional biometrics where the majority of the macroinvertebrates collected belonged to a single taxonomic group in many of these upstream stations. Also, based on the relatively low number of Scraper taxa and high number of percent Collector - Gatherers at the PD-8 and PD-9 stations, results could be due to increased sediment filling in the available niche space for the more sensitive functional feeding group. The higher turbidity and TSS values recorded from the October 6, 1998 samples at both of these locations may also indicate that this is an area of excessive sediment deposition. FINAL ASSESSMENT AND SIGNATURE A review of physical, chemical and biological observations on Prairie Dog Creek indicate that Prairie Dog Creek is fully supporting protection and propagation of cold water fish. Chemical data and Wyoming Game and Fish documentation suggest the presences of healthy Brown trout population. EnTechs data did suggest that temperature exceedences can occur but is unclear to the extent of the problem. Additional temperature monitoring may be required. A review of chemical, biological, and physical data collected on Prairie Dog Creek suggest that Prairie Dog Creek is fully supporting non-fishery aquatic life use. Although Prairie Dog Creek is clearly impacted by anthropogenic activities the marcoinvertabrate community appears to be adapted and healthy. A review of E. coli data collected on Prairie Dog Creek suggest that Prairie Dog Creek is not supporting contact recreation water use. Currently, Prairie Dog Creek is listed on Wyoming s 2004 draft 305(b) list for contact recreation. 11

12 A review of the biological and chemical data collected on Prairie Dog Creek indicate that Prairie Dog Creek is fully supporting drinking water, agricultural, industrial and aesthetic value. Author Date Monitoring Program Supervisor Date 12

13 REFERENCES EnTech Prairie Dog Creek Watershed Mater Plan. Level I Study. En Tech, Inc. Consulting Engineers. Sheridan, WY. Jessup, B.K., and J.B. Stribling Further evaluation of the Wyoming stream integrity index, considering quantitative and qualitative reference site criteria. October, Tetra Tech, Inc., Owings Mills, MD. King, K A bioassessment method for use in Wyoming stream and river water quality monitoring. Draft. Wy. Dept. Env. Qual., Water Qual. Div., Cheyenne, WY 84 pp. King, K. 1993a. A laboratory manual and illustrated guide to orders of common Wyoming stream macroinvertebrates. Wy. Dept. Env. Qual., Water Qual. Div., Cheyenne, WY 68 pp. Lloyd, D Turbidity as a water quality standard for salmonid habitats in Alaska. North American Journal of Fisheries Management. 7: pp. Merritt R.W., and Cummins K.W An introduction to the aquatic insects of North America. Third Edition. Kendall/Hunt Publishing Company. Dubque, Iowa. Newcombe, C.P. and J.O.T. Jensen Channel suspended sediment and fisheries: a synthesis for quantitative assessment of risk and impact. North American Journal of Fisheries Management. 16(4): Omernik, J. M. and A. L. Gallant Ecoregions of the west-central United States (map). U. S. Environmental Protection Agency, Corvallis, OR. Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes Rapid bioassessment protocols for use in streams and rivers. Office of Water (WH-553), EPA/444/ Washington, D.C. Rosgen, D Applied river morphology. Illustrated by H.L. Silvey. Wildland Hydrology, Pagosa Springs, CO. U. S. Environmental Protection Agency Quality criteria for water: Office of Water Regs. And Standards. Washington, D.C. Water Resources Data System Wyoming statewide water resources data inventory. Whittaker, Mike State Board of Control. Personal Conversation. November 28,

14 Winget, R. N. and F. A. Mangum. A biotic condition index: Integrated biological, physical, and chemical stream parameters for management. U. S. D. A. Forest Service. Ogden, UT. 51 pp. WDEQ/WQD Beneficial use reconnaissance project-wadeable stream monitoring methodology. Wyoming Department of Environmental Quality, Water Quality Division, Cheyenne, WY. WDEQ/WQD Manual of standard operating procedures for sample collection and analysis. Wyoming Department of Environmental Quality, Water Quality Division, Cheyenne, WY. WDEQ/WQD. 2001a. Quality assurance project plan (QAPP) for Beneficial Use Reconnaissance Program (BURP) water quality monitoring. Water Quality Division, Cheyenne, WY. WDEQ/WQD. 2001b. Wyoming Surface Water Classification List (Table A). June 21, 2001 update. Water Quality Division, Cheyenne, WY. WDEQ/WQD. 2001c. Water Quality Rules and Regulations: Chapter 1. Wyoming Surface Water Quality Standards. Water Quality Division, Cheyenne, WY. WDEQ/WQD2001d. Water Quality Rules and Regulations: Chapter 8. Wyoming Surface Water Quality Standards. Water Quality Division, Cheyenne, WY. WDEQ/WQD Wyoming s method for determining water quality condition of surface waters. Wyoming Department of Environmental Quality, Water Quality Division, Cheyenne, WY. Wyoming Game and Fish Department Fish inventory for Prairie Dog Creek Wyoming Oil and Gas Resource Assessment Mapper website (WOGRAM) University of Wyoming. Wyoming Geographic Information Science Center. ( 14

15 Table 1. WDEQ station information for Prairie Dog Creek and tributaries. Station name (ID code) Section/ Town/Range North Latitude West Longitude USGS 7 1 / 2 ' Quadrangle 1:100,000 BLM Map Prairie Dog Creek above Jenks Creek (PD-1) SESW Sec 27 T54N/R83W 44 37' 08.43" ' 35.39" Banner Sheridan Jenks Creek (JC-1) SESW Sec 27 T54N/R83W 44 37' 02.76" ' 33.36" Banner Sheridan Prairie Dog Creek Below Jenks Creek (PD-2) NESW Sec. 27 T54N/R83W 44 37' 11.70" ' 37.41" Banner Sheridan Prairie Dog Creek Above Murphy Gulch (PD-3) NENE Sec. 27 T54/R83W 44 37' 47.98" ' 06.08" Buffalo Run Creek Sheridan Murphy Gulch (MG-1) NWSW Sec. 14 T54?R83W 44 39' 13.94" ' 42.27" Buffalo Run Creek Sheridan Prairie Dog Creek below Murphy Gulch (PD-4) SWSE Sec. 10 T54/R83W 44 39' 34.76" ' 12.34" Buffalo Run Creek Sheridan Prairie Dog Creek above Meade Creek (PD-5) NESE Sec. 33 T55N/R83W 44 41' 40.91" ' 09.75" Buffalo Run Creek Sheridan Meade Creek (MC-1) SWSE Sec. 28 T55N/R83W 44 42' 16.15" ' 27.69" Buffalo Run Creek Sheridan Prairie Dog Creek below Meade Creek (PD-6) SWSE Sec. 28 T55N/R83W 44 42' 18.91" ' 30.40" Buffalo Run Creek Sheridan Prairie Dog Creek below Hwy 14 (PD-7) Prairie Dog Creek above Wildcat Creek (PD-8) NWSW Sec. 17 T55N/R83W NENW Sec. 9 T56N/R83W 44 44' 20.07" ' 43.38" Big Horn Sheridan 44 50' 50.96" ' 51.70" Wyarno Sheridan Wildcat Creek (WC-1) NENW Sec. 9 T56N?R83W 44 50' 52.90" ' 49.28" Wyarno Sheridan Prairie Dog Creek below Wildcat Creek (PD-9) SESW Sec. 4 T56N/R83W 44 51' 50.96" ' Wyarno Sheridan 15

16 Table 2. Criteria for narrative assessment and determination of aquatic life use support in the Northwestern Great Plains bioregion. Aquatic life use support status Narrative assessment Percentile of reference index values WSII score Full-support Very good - >77.5 Full-support Good 25th Partial-support Fair <25th Non-support Poor Non-support Very Poor - <

17 Table 3. Station characteristics of Prairie Dog Creek and tributaries PD-1 PD-2 PD-3 PD-4 PD-5 PD-6 PD-7 PD-8 PD-9 JC-1 MG-1 MC-1 WC-1 Elevation (ft) Bedrock Wasatch Wasatch Wasatch Wasatch Quaternary geology 1 alluvium Quaternary alluvium Quaternary alluvium Quaternary alluvium Quaternary alluvium Wasatch Quaternary alluvium Quaternary alluvium Quaternary alluvium Soils 1 Hesperus Variant- Reget Hesperus Variant- Reget Hesperus Variant- Reget Coliams Worthento n Coliams Worthento n Coliams Worthento n Worthento n-recluse Haverdad- Worthento n Haverdad- Worthento n Hesperus Varaint- Reget Moskee- Nuncho ColiamsW orthenton Haverdadworthenton Primary Land use Livestock grazing Livestock grazing Livestock grazing Livestock grazing Irrigated hayland Livestock grazing Secondary land use Recreation /Wildlife Recreation /Wildlife Recreation /Wildlife Recreation /Wildlife Livestock grazing Recreation /Wildlife Discharge 4.45/ / / / / / / / / / / / /2.14 (cfs) 2 Drainage area (mi 2 ) Stream order 3 Stream C4 F3 C4 F4 F5 C4 C4 F5 F5 C3 E5 E4 - type 3 1 WOGRAM (2002) 2 at the time of sampling 3 Rosgen 17

18 Table 4. Prairie Dog Creek and tributary water quality data, October 6, Parameter (Units) PD-1 JC-1 PD-2 PD-3 MG-1 PD-4 PD-5 MC-1 PD-6 PD-7 PD-8 WC-1 PD-9 Time (hours) Temperature (C ) ph Conductivity (µs/cm) Dissolved Oxygen (mg/l) Turbidity (NTU) Total Suspended Solids (mg/l) < Total Dissolved Solids (mg/l) Alklinity (mg/l) Chlorides (mg/l) <5 <5 <5 <5 <5 <5 <5 <5 <5 <5 <5 8 <5 Sulfate (mg/l) < Total Hardness (mg/l) Total Phosphorus (mg/l) 0.1 <0.1 <0.1 < <0.1 < Nitrate Nitrogen (mg/l) <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 < <

19 Table 5. Prairie Dog Creek and tributary water quality data, November 23, Parameter (Units) PD-1 JC-1 PD-2 PD-3 MG-1 PD-4 PD-5 MC-1 PD-6 PD-7 PD-8 WC-1 PD-9 Time (hours) Temperature (C ) ph Conductivity (µs/cm) Dissolved Oxygen (mg/l) Turbidity (NTU) Total Suspended Solids (mg/l) <2 <2 <2 <2 < < Total Dissolved Solids (mg/l) Alklinity (mg/l) Chlorides (mg/l) <5 <5 <5 <5 7 <5 5 <5 <5 <5 <5 6 <5 Sulfate (mg/l) < Total Hardness (mg/l) Total Phosphorus (mg/l) <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 < <0.1 <0.1 <0.1 <0.1 <0.1 Nitrate Nitrogen (mg/l) <0.1 < < <0.1 < <

20 Table 6. Substrate composition, weighted embeddedness, and average water velocity at Prairie Dog Creek and tributary assessment stations, October Substrate PD-1 JC-1 PD-2 PD-3 PD-4 PD-5 MC-1 PD-6 PD-7 PD-8 PD-9 Cobble (2.5-10") 29% 63% 54% 12% 11% 38% 67% 19% 62% 0% 0% Coarse Gravel (1-2.5") Fine Gravel (0.3-1") Sand ( 0.3", gritty) Silt * ( 0.3", fine) Clay (Hard Pack) Organic (fine, black) Precipitate (Oil, WWTF) Weighted Embeddedness Mean Velocity (ft/sec)

21 Table 7. Habitat Scores for Prairie Dog Creek and tributary assessment stations, Parameter (points possible) PD-1 PD-2 PD-3 PD-4 PD-5 PD-6 PD-7 PD-8 PD-9 Bottom Substrate/Percent Fines (20) Embedddedness (20) Instream Cover For Fish (20) Velocity/Depth (20) Channel Flow Status (20) Channel Shape (15) Pool/Riffle Ratio (15) Channelization/Alteration (15) Width to Depth (15) Bank Vegetation Protection (10) Bank Stability (10) Disruptive Pressures (10) Riparian Vegetative Zone Width (10) Total Score

22 Table 8. Individual metric values, metric scores, cumulative index value and narrative condition rating for Prairie Dog Creek and tributaries. Core 5 th or 95 th percentile of reference data Value PD-1 Score PD-1 Value JC-1 Score JC-1 Value PD-2 Score PD-2 Value PD-3 Score PD-3 Value PD-4 Score PD-4 Total Number Taxa Ephemeroptera Taxa Plecoptera Taxa Trichoptera Taxa % Plecoptera % Trichoptera (no Hydro) % non-insects * % scrapers BCI CTQa* Semi-voltine Index Score Narrative Rating Good Good Good good good * The macroinvertebrate data for PD-3 did not meet data quality objectives for precision. 22

23 Table 8. (continued) Core Value PD-5 Score PD-5 Value MC-1 Score MC-1 Value PD-6 Score PD-6 Value PD-7 Score PD-7 Value PD-8 Score PD-8 Value PD-9 Score PD-9 Total Number Taxa Ephemeroptera Taxa Plecoptera Taxa Trichoptera Taxa % Plecoptera % Trichoptera (no Hydro) % non-insects * % scrapers BCI CTQa* Semi-voltine Index Score Narrative Rating good fair good good good good 23

24 Table 9. Supplemental metric values for all Prairie Dog Creek and tributary bioassessment stations. Supplemental s Values PD-1 Values JC-1 Values PD-2 Values PD-3 Values PD-4 Values PD-5 Values MC-1 Values PD-6 Values PD-7 Values PD-8 Values PD-9 Ratio Scraper / Filtering Collector Ratio EPT Taxa / Chironomidae Abundance % Dominant Taxa % Chironomidae Abundance % Hydropsychidae / Total Trichoptera % Multivoltine % Univoltine % Semivoltine Modified HBI

25 Table 10. Historical water quality data collected in 1992 by the Wyoming Department of Environmental Quality, Water Quality Division. Parameter PD-1 JC-1 PD-2 PD-5 Temperature C ph (su) Conductivity (µs/cm) Dissolved Oxygen (mg/l) Turbidity (NTU) TSS (mg/l) Alkalinity (mg/l) Chlorides (mg/l) Sulfate (mg/l) Total Hardness (mg/l) Total Phosphorus (mg/l) Nitrate Nitrogen (mg/l)

26 Table 11. Prairie Dog Creek near confluence with Tongue River, fish species and their characteristics. Species Name Game / Nongame 1 Cold- / Warmwater 2 Native / Introduced 3 Brown Trout Gamefish Coldwater Introduced White Sucker Nongame Fish Coldwater Native Mountain Sucker Nongame Fish Coldwater Native Longnose Dace Nongame Fish Coldwater Native Flathead Minnow Nongame Fish Coldwater Native Creek Chub Nongame Fish Coldwater Native Stonecat Nongame fish Coldwater Native White Crappie Gamefish Warmwater Introduced Flathead Chub Nongame fish Coldwater Native Plains Minnow Nongame fish Coldwater Native Sand Shiner Nongame Fish Coldwater Native Carp Nongame Fish Coldwater Introduced Shorthead Redhorse Nongame Fish Coldwater Native 1 Wyoming Department of Environmental Quality, Chapter 1 Water Quality Standards (1998) 2 Wyoming Department of Environmental Quality, Chapter 1 Water Quality Standards (1998) for gamefish species. Wyoming Game and Fish Stream and Lakes Database for nongame fish species. 26

27 Table 12. Prairie Dog Creek macroinvertebrate data, 1992 and 1998 collections at three stations. Above Jenks Cr. Below Jenks Cr. Above Meade Cr Total Number Taxa Ephemeroptera Taxa Plecoptera Taxa Trichoptera Taxa % Plecoptera % Trichoptera (no Hydro) % non-insects % scrapers BCI CTQa Semi-voltine WSII Scoring* WSII Rating* Good Good Good Good Good Good * The WSII Scoring and Rating system is based on collections made with 500 µm mesh 27

28 Table 13. Fecal Coliform bacteria (number/100 ml) analyses for samples collected in the Prairie Dog Creek drainage by EnTech. Site Descriptions Sampling dates 10/11/2000 2/1/2001 4/26/2001 6/21/2001 8/16/2001 Prairie Dog Ditch Prairie Dog Creek above Hwy Jenks Creek Prairie Dog Creek below confluence with Jenks Creek Prairie Dog Creek below confluence with Murphy Gulch Prairie Dog Creek below confluence with Meade Creek Prairie Dog Creek above Highway Prairie Dog Creek below confluence with Wildcat Creek Prairie Dog Creek below confluence with Dutch Creek Prairie Dog Creek below confluence with Coutant Creek Prairie Dog Creek above confluence with Tongue River

29 Table 14. Additional descriptive information for Prairie Dog Creek E. coli collection sites. EC-1 EC-2 EC-3 EC-4 EC-5 EC-6 Quarter NE SW NW NE NE NE SW SE NW NW SW SW Section Township Range Latitude Longitude Land Use Livestock grazing, recreation and wildlife, irrigated hayland Livestock grazing, recreation and wildlife, irrigated hayland Livestock grazing, recreation and wildlife, irrigated hayland Irrigated hayland, limited livestock grazing, recreation and wildlife Irrigated crop row/hayland, limited livestock grazing, recreation and wildlife Irrigated crop row/hayland, limited livestock grazing, recreation and wildlife 29