Wise River Stream Corridor Assessment

Home , Cut Bank Creek, Marias River, Two Medicine River

Marias River (Bear River: Kai’yo Isisakta) Stream Corridor Assessment

Final Report

Marias River upstream from I-15 Crossing

May 2008

Marias River Stream Corridor Assessment (Bear River: Kai’yo Isisakta)

Final Report

Prepared for the: Marias River Watershed Liberty County Conservation District Toole County Conservation District Glacier County Conservation District Pondera County Conservation District Big Sandy Conservation District

May 2008

Prepared by:

Warren Kellogg – Watershed Specialist USDA Natural Resources Conservation Service Helena, MT

TABLE OF CONTENTS

1. INTRODUCTION……………………………………………………………………..……………….…1

1.1 Purpose for the Stream Assessment……...... …………………………………….2 1.2 Acknowledgements...... 2

2. BACKGROUND INFORMATION...... 3

2.1 General Watershed Description…..…………………………………………………………….…3 2.2 Brief History………………………………………………………………………………………4 2.3 Hydrology…………………………………………………………………………………………5 2.4 Land Use…………………………………………………………………………………………..6 2.5 Fisheries…………………………………………………………………………………………...6 2.6 Wildlife……………………………………………………………………………………………8

3. ASSESSMENT METHODOLOGY……………………………………………………………………...9

3.1 Water Chemistry…………………………………………………………………………………..9 3.2 Aquatic Invertebrates……………………………………………………………………………...9 3.3 Periphyton and Chlorophyll A……………………………………………………………………10 3.4 Riparian Health/Physical Channel Conditions……………………………………………………10

4. OBSERVATIONS AND LAB ANALYSIS SUMMARY……………………………………………….12

4.1 Two Medicine River………………………………………………………………………………12 4.2 Cut Bank Creek…………………………………………………………………………………...12 4.3 Marias River………………………………………………………………………………………13 4.4 Teton River………………………………………………………………………………………..13 4.5 Additional Water Quality Information……………………………………………………………14

5. MARIAS RIVER REACH SUMMARIES: REACHES 1 TO 15...... ………………………………15

6. PLANNING CONSIDERATIONS……………………………………………………………………….79

7. REFERENCES CITED……………………………………………………………………………………84

8. APPENDIX A: MARIAS RIVER ASSESSMENT SITES...... 85

i 1. Introduction

The Marias River Watershed (MRW) is a collection of landowners, conservation districts, and the Blackfeet Tribe who share a common goal of protecting and improving the land, water, and resources of the Marias River watershed. The MRW is committed to the following objectives (Marias River Watershed Operating Guideline, 2007):

Lifestyle To provide support for and to preserve the independent way of life known as “ranching and/or farming” and to help educate the general public about the necessity of said activities as they relate to the economic health of the watershed and the state.

Resources To become educated about and to put into effect the most practical means of preserving and improving the resources of the watershed; to protect the water quality, grazing lands, riparian habitat, and fish and wildlife habitat and; to promote sound and efficient use of the water both in streams and from underground sources. The overall goal is to maintain the resources of the Watershed for both present and future generations.

Weeds To seek and use an integrated approach to control the spread of noxious weeds consistent with improving the land and the range.

Fish and Wildlife To promote sound game and fish management that will insure the existence of sustainable numbers of game birds, game animals, game fish and other native species and try to maintain them in balance with the habitat that support these species.

The purpose of the MRW organization is to seek a better understanding of the Marias River and its tributaries by conducting resource assessments where information is lacking and to seek agreements among individuals and groups on water use and land improvements in the Marias River Watershed. The MRW was established in 2002 by local landowners who felt that a locally-led watershed group was needed to effectively address priority resource issues in the Marias River Basin. Such issues included: water quality regulations, water use efficiency, recreational access conflicts, accelerated stream bank erosion, and noxious weed infestations.

The MRW Executive Board is composed of 18 official members who represent conservation districts, landowners, and the Blackfeet Tribe. The MRW functions as an open forum for discussions on watershed issues, an information resource for landowners in the watershed, a clearing house for natural resource information, a liaison between management agencies and the public, and a catalyst for voluntary conservation and conservation efforts.

1.1 Purpose for the Stream Assessment

The objectives for the Marias River stream corridor assessment were to: • Evaluate the fluvial geomorphology of the Marias River to determine how channel behavior has responded to natural processes and human influences over time. The geomorphic

1 evaluation would look specifically at the extent and impacts of noxious weed infestations, stream bank erosion, transportation corridor impacts, stream bank stabilization measures, and in-channel infrastructure (irrigation, stream crossings, etc.). • Evaluate how riparian vegetation characteristics have been influenced by channel types and land management practices. • Provide various historic and current aerial photos that serve as a baseline for monitoring trends in the river channel migration, riparian vegetation, and adjacent land use. • Identify opportunities and assist the MRW in setting priorities for improving/maintaining stream channel stability, riparian plant community health, and fish habitat.

The scope of the stream corridor assessment includes the entire 210 miles of the Marias River mainstem. The fieldwork was completed during the summers of 2005 and 2006 by Warren Kellogg (NRCS Watershed Specialist) and Roger Zentzis (MRW Technical Coordinator).

1.2 Aknowledgements

The members of the Marias River Watershed (MRW) are also to be commended for their investment of time and interest in providing the necessary leadership and project direction. The following people dedicated time and effort in the planning and implementation of this comprehensive stream corridor assessment: • Roger Zentzis, MRW Technical Coordinator • Marlene Moon, Liberty County CD Administrator • Gloria Mason, Glacier County CD Administrator • Kody Farkell, Pondera County CD Administrator • Sara Shepard, Toole County CD Administrator • Sonia Silvan, Big Sandy and Chouteau County CD Administrator

2 2. Background Information

2.1 General Watershed Description

The Marias River is a tributary of the Missouri River, approximately 210 mi (338 km) long, exclusively in Montana. Much of the headwaters lie within the Blackfeet Nation’s land with the exception of the Dupuyer Creek drainage. The mainstem Marias River is formed by the joining of Cut Bank Creek and the Two Medicine River. It flows east into Lake Elwell (Tiber Reservoir), then continues east through Liberty and Hill Counties before taking a sharp turn to the south, eventually taking in the Teton River near Loma, 2 miles above its confluence with the Missouri River.

The river was explored in 1805 by the Lewis and Clark Expedition. Some of the men on the expedition mistook it for the main branch of the Missouri until their subsequent discovery of the Great Falls of the Missouri near Great Falls, Montana. The river was named by Meriwether Lewis after his cousin, Maria Wood. Prior to the Lewis and Clark Expedition, the Blackfeet people referred to the river as the Bear River or Kai’yo Isisakta (Apiisoomahka 1993).

The Marias River basin comprises approximately 5.8 million acres that begins high on the continental divide at elevations of about 10,000 feet. The Marias River watershed starts out in mountainous terrain in Glacier Park transitioning into gently rolling foothills and eventually into a generally level prairie landscape as the river flows east. The following are the major sub- basins that comprise the Marias River Basin:

Cut Bank Creek Watershed: 770,466 acres Two Medicine River Watershed: 840,934 acres Willow Creek Watershed: 639,151 acres Teton River Watershed: 1,219,104 acres Marias River Mainstem: 2,337,723 acres

The Marias River basin lies in the heart of the Golden Triangle and is one of the world’s leading grain-producing areas, annually producing more than 50% of the state’s grain (MBMG 2005). It is predominately dryland farming on the uplands and some irrigated farmland along the major streams and headwater regions. Recreation has become increasingly important on the Marias River. The area receives a moderate amount of fishing and hunting pressure and is becoming more popular with floaters. Angling pressure is high on the lower 6 miles of the river during the spring spawning season.

2.2 Brief History

The valley of the Marias was a favorite winter camping site for the Blackfeet, especially for the Piegan or Pikuni bands (Hamaker 1967). It is believed that more ancient tribes may have been the first occupants along the Marias; but, the Blood and Piegan bands were certainly present when Lewis and Clark traveled through in 1805 and 1806.

Trading posts were built in the area by the early 1830s. Fort Piegan was the first, located at the mouth of the Marias River. Several fur trading posts came and went over the next 50 years. As non-indigenous people arrived in this part of Montana, so came the small pox epidemics that ultimately decimated the Blackfeet people. This was culminated by the tragic Bear River massacre of Heavy Runners band in 1870. By 1900, the Blackfeet became a demoralized people squeezed on a reservation that had been incrementally downsized by a series of one-sided treaties.

Following the Civil War, increasing numbers of white settlers began to arrive in Montana. Livestock production began in the 1880s with large cattle companies dominating the region until the drought of 1903. Public lands suitable for agriculture were homesteaded in tracts of 160 and 320 acres between 1908 and 1914. From 1917 to 1920, drought prevailed and many farms were abandoned. As a result, farm operations increased in size and today, the average dryland farm

4 unit consists of more than 1,600 acres. Several large irrigation projects were constructed in the late 1800s and early 1900s with most of the water diverted from headwater tributaries and storage reservoirs. The irrigated lands lie mostly in the southwestern region of the Basin.

2.3 Hydrology

Long-term USGS flow records are available for the Marias River near Shelby and below Tiber Dam near Chester. Late spring snowmelt often brings large quantities of water into the Marias River beginning in May. Peak flows are typically received in June. The more recent flood events took place in 1975 and 1964. The following were the largest flow events over the last 105 years in order of magnitude: 1. 1964: 241,000 cfs at the Shelby gage station (June 9, 1964). This extremely high flow was due to the failure of Swift Dam. Tiber Dam buffered most of that peak as the high was only 10,400 cfs below Tiber Dam recorded at the Chester gage station (June 16, 1964). 2. 1975: 75,700 cfs at the Shelby gage station (June 20, 1975). Below Tiber Dam, the peak was 5, 840 cfs on June 24, 1975. 3. 1908: 70,000 cfs estimate. 4. 1948: 40,000 cfs at the Shelby gage station (June 18, 1948). Downstream from the Chester Highway Bridge (June 19, 1948), the peak was 50,700 cfs recorded at the Brinkman gage station. (the Brinkman gage station was discontinued in 1956 after Tiber Dam was completed).

Discharge rapidly declines in July when precipitation is considerably less and most of the seasonal snowpack has melted. The following tables show monthly mean discharges at various stations in the Marias River basin:

Marias River Near Shelby Period of Record: 1902 to Present (continuous) J F M A M J J A S O N D Discharge 253 316 575 1,120 2,660 3,010 1,020 377 348 397 392 301

Marias River near Chester Period of Record: 1956 to Present (continuous) J F M A M J J A S O N D Discharge 412 450 599 788 1,170 1,630 1,180 891 822 715 580 445

Marias River at Loma Period of Record: 1959 to Present (discontinued from 1972 to 2001) J F M A M J J A S O N D Discharge 298 434 568 778 1,120 1,860 1,160 1,010 943 830 723 402

5 Pondera Coulee near Mouth Period of Record: 1975 to 1985 J F M A M J J A S O N D Discharge 0.80 0.59 85 17 8.2 10 8.0 9.0 4.1 9.8 0.98 0.30 * There are times when there is no flow at this site, especially late fall and winter months.

Teton River near Mouth Period of Record: 1998 to Present J F M A M J J A S O N D Discharge 15 20 66 60 33 101 24 8.2 6.0 12 19 16 * During the late summer and early fall, there are frequent occasions when there is no flow.

Present day flow regimens of the lower Marias River are completely regulated by the Tiber Dam operation. Since its completion in 1956, Tiber Dam and Lake Elwell have served important functions in flood control, recreation, fish and wildlife, municipal and regional rural water systems (BOR). A minimum flow is maintained in the river below Lake Elwell to meet downstream demands, such as stock water, support of fish and wildlife, and other downstream water rights.

The 400,838 acre-foot capacity of Lake Elwell is allocated exclusively to flood control for the lower Marias River and the Missouri River.

2.4 Land Use

Land uses in the Marias River basin are fairly diverse. In the forested areas of the upper basin, a considerable portion is in designated wilderness (Bob Marshall Wilderness Area) and Glacier National Park. US Forest Service lands outside the wilderness areas are managed for semi- primitive recreation and multiple use. In the middle and lower basin, grain and hay production and livestock grazing are principal uses. Most of the land in this area if privately owned with a few scattered parcels of federal and state managed lands.

The largest user of water in the Marias Basin is irrigated agriculture. Over 200,000 acre-feet or 34% of the average annual flow may be consumed during an average year (FWP 1989). Including Lake Elwell, four other reservoirs in the basin have storage capacities greater than 1,000 acre-feet. All except Lake Elwell are used primarily for irrigation.

2.5 Fisheries

From the confluence of the Two Medicine River and Cut Bank Creek to the head of Lake Elwell (approximately 60 miles), the fishery is primarily a warmwater fishery where walleye are the most abundant game fish. Walleye use the upper Marias for spawning and rearing. A segment of the population remains in the river throughout the summer. Coldwater game fish also inhabit this reach, but in lower numbers. The average size for Rainbow trout is large, averaging nearly 2 pounds, but are found in the river mainly in the spring and early summer, preferring Lake Elwell during the rest of the year. Other game fish found in the upper Marias, in relatively low numbers, include mountain whitefish, burbot, northern pike, and channel catfish. Eleven non- game fish species have been sampled in this reach with flathead chub, longnose dace, and

6 longnose suckers being the most abundant (FWP, 1989). FWP has an instream water right of 200 cfs with a priority date of July 1, 1985.

In the mid-1950s, the upper Marias River was chemically treated with toxiphene to rid it of “rough” fish as the newly built Lake Elwell was being managed as a coldwater fishery. The impacts on native fish were undoubtedly severe and may still be reflected in the current assemblage of fish.

Lake Elwell was completed in 1956 and has since served as an important recreational destination. Up until the early 1970s, the lake was managed as a trout sport fishery. Then, in the early 1970s, the lake was stocked with walleye. It has been managed for walleye, northern pike, and perch ever since. Other than forage fish, the lake hasn’t been stocked since 1974 (per comm. Dave Yerk, FW&P).

Recent fish surveys have found a few remnant Shovelnose Sturgeon in Lake Elwell, but the species appears to not be reproducing and may not be sustained. There may be Shovelnose Sturgeon in the upper river. Fish surveys have not captured any, but antidotal information from anglers indicates that there may be some resident fish in the upper river.

From Tiber Dam to Circle Bride (Highway 223), approximately 21 miles, cold water releases from Tiber Dam have altered the aquatic environment to favor salmonid species. Mountain whitefish exist in high numbers and are the most abundant game fish in this reach. Rainbow and brown trout occur in fair numbers, exhibiting excellent growth rates and attaining exceptionally large sizes. There is an on-going stocking program of rainbow and brown trout in this reach. Warmwater game fish, including sauger, walleye, northern pike, and burbot also inhabit this reach, but in low numbers. Fourteen non-game fish have been sampled in this reach with longnose dace and longnose sucker being the most abundant (FWP, 1989). FWP has an instream water right along this section for 419.5 cfs with a priority date of July 1, 1985.

From Circle Bridge to the mouth (57 miles), the fishery reverts to a warmwater fisheries in which sauger are the most abundant resident game fish. Walleye occur in fair numbers and are more numerous in the lower portion of the reach. Channel catfish are found in moderate numbers throughout the lower Marias. Game fish which migrate from the Missouri River into the Marias to spawn are shovelnose sturgeon, sauger, walleye, and channel catfish. A moderate population of mountain whitefish and an occasional brown trout are the coldwater fish found throughout the lower river. Sixteen resident non-game fish have been sampled in the lower Marias River with goldeye, flathead chub, longnose dace, and longnose sucker being the most abundant. The FW&P instream flow for this section is 488.5 cfs with a priority date of July 1, 1985.

Over the last 20 years, increased attention has been given to the federally endangered pallid sturgeon. Antidotal information and old photographs make a strong case that the Marias River was historically an important river for this species. In recent years, there have been attempts to simulate high flow events during the early summer to encourage pallid sturgeon use of the river for spawning. Drought and low run-off conditions have stymied the implementation of this effort.

2.6 Wildlife

Big game species found along the Marias River include mule and white-tailed deer. Antelope are common on the bench above the river. Game birds present are sharp-tailed grouse, ring- necked pheasant, and Hungarian partridge. Beaver, mink, muskrat, and raccoon are the furbearers found associated with the river habitat. Several species of waterfowl and shorebirds are attracted to the Marias River during their migration period and throughout the ice-free period. The river is especially important for Canada goose nesting and great blue heron rookeries.

8 3. Assessment Methodology

Standard sampling techniques were used to characterize the water chemistry, aquatic insect community, periphyton (algae that are attached to or in close proximity of the river bottom), and the riparian/channel geomorphology of the Marias River and Pondera Coulee. The observations and planning considerations included in this report are based upon this assessment data as well as on professional experience and discussion with local landowners and agency representatives.

3.1 Water Chemistry

Samples were collected and preserved using methods specified by Montana Department of Environmental Quality’s (DEQ) Standard Operating and Procedures. All samples were analyzed by Energy Laboratories, Inc. located in Helena, Montana. Parameters analyzed were nutrients, total recoverable metals, dissolved metals, inorganics, and total suspended solids (TSS).

Additional field readings were taken using a U-10 Horiba field meter at each of the sample sites to obtain pH, specific conductance (similar to dissolved solids), and water temperature.

Water chemistry samples were collected four times: August 2005, March 2006, October 2006, and March 2007. Refer to Appendix A for the locations where the samples were collected.

3.2 Aquatic Invertebrates

Aquatic invertebrates are known to be important indicators of stream health. Their long lives, complex life cycles, and limited mobility mean that there is plenty of time for the invertebrate community to respond to the cumulative effects of its surrounding environment.

Samples were collected on seven sites in August 2005. Four sites were located on the Marias River and the others upstream from the mouths of the Two Medicine River and Cut Bank Creek. Pondera Coulee was sampled approximately one mile upstream from the Bootlegger Trail crossing. At each of the seven sites, a traveling kick sample was collected and the habitat visually evaluated. All samples were preserved using ethanol and delivered to Rhithron Associates, Inc. in Missoula, MT for analysis. Field sampling and laboratory/data analysis followed the Montana DEQ Rapid Bioassessment Protocols. Analysis of the samples was done by Rhithron Associates, Inc. Refer to Appendix A for the specific locations where the aquatic invertebrate samples were collected.

Aquatic Insect Periphyton (Algae)

3.3 Periphyton and Chlorophyll A

Periphyton is the diverse assemblage of generally microscopic organisms that occur in aquatic habitats as a biofilm of varying thickness attached to submerged surfaces. Algae typically dominate the periphyton community in freshwater streams. Algae are useful as water quality indicators because they occur in very large numbers, are highly sensitive to physical and chemical factors, and have known responses to environmental conditions and pollution tolerances unique to individual species.

Chlorophyll A is a photosynthetic pigment found in most algae. Concentrations of chlorophyll A provide a surrogate measure of algal biomass and nutrient availability in the water.

Periphyton and Chlorophyll A samples were collected following standard operating procedures of the DEQ. Samples were collected at the same locations and date (Aug. 2005) as the aquatic macroinvertebrates samples. The lone exception was the Pondera Coulee site where a periphyton sample was not collected. Periphyton samples were analyzed by Erich Weber, PhycoLogic, located in East Helena, MT. and the chlorophyll samples were analyzed by Energy Labs, Inc. in Helena.

3.4 Riparian Health/Physical Channel Conditions

The riparian and physical condition of the stream corridor was visually appraised by assessing functional condition at multiple sites along the Marias River and Pondera Coulee. This standard assessment procedure (USDA Natural Resources Conservation Service 2000) provides a systematic evaluation of channel condition, hydrologic alterations, streambank stability, and riparian health. A numerical rating was assigned to each site placing them into one of the following categories:

Sustainable: 85-100% - Stream and associated riparian area have certain expected attributes (i.e., floodplain access, adequate riparian vegetation, stable channel characteristics) in place and fluvial processes (i.e., energy dissipation, sediment trapping) are working as they should be.

10 At Risk: 50-75% - Most of the attributes and fluvial processes are in place and working. Certain necessary attributes and processes may be lacking for long-term stability and function of the reach.

Not Sustainable: Less than 50% - Stream and riparian area are clearly lacking adequate vegetation, stable channel characteristics, etc., that won’t allow energy dissipation, sediment trapping, bank building, or any of the other fluvial processes expected for long-term stability.

All riparian sites were GPS located and photographed. Specific site locations are listed in Appendix A.

Paula Gunderson and Warren Kellogg completing a riparian assessment at a site on the upper Marias River. A key item of the assessment is to evaluate the age and species diversity of the riparian vegetation and determine its ability to sustain itself over time.

11 4. Observations & Lab Analysis Summary

The water chemistry, aquatic invertebrate, and periphyton reflect the water quality and stream health of the Marias River and Pondera Coulee for a short instance in time. These indicators can change significantly both spatially and temporally during certain flow events, seasons of the year, and in response to new disturbances. To fully understand the quality of water and long- term trends, it is important to institute a monitoring program that will encompass the variables mentioned above over a period of years. All lab analysis and reports referenced below are available at the Liberty County Conservation District office in Chester.

4.1 Two Medicine River (mouth)

¾ Water Chemistry: The Two Medicine River has a visible sediment plume where it joins with Cut Bank Creek to form the Marias River. The plume is often visible as far as one mile downstream from the confluence before it becomes fully mixed. Total suspended sediment (TSS) in the Two Medicine River is typically 3 to 5 times higher than Cut Bank Creek, and even more so during high flow events. The relative concentrations of phosphorus and TSS concentrations between the Two Medicine River and Cut Bank Creek are closely related since phosphorus tends to attach to sediment particles. ¾ Aquatic Invertebrates: The bioassessment score at this site was higher than all other sites sampled during this assessment. The assemblage of aquatic invertebrates was characteristic of a large plains region river. Good water quality, cool-to-warm water temperatures, and diverse instream habitats are implied. ¾ Periphyton: Diatom metrics showed excellent biological integrity with full aquatic life use support, when compared to criteria for prairie streams. Under criteria developed for mountain streams, minor impairment is indicated due to sediment and organic nitrogen, but with good biological integrity and full support of aquatic life uses.

4.2 Cut Bank Creek (mouth)

¾ Water Chemistry: Cut Bank Creek consistently has higher concentrations of inorganics (i.e. sulfate, alkalinity, chloride, hardness, etc.), dissolved metals (i.e. calcium, magnesium, potassium, and sodium), and nitrogen than that found in the Two Medicine River. Most concentrations are not high enough to pose a major water quality problem, but the Cut Bank Creek site should continued to be monitored to determine future trends. ¾ Aquatic Invertebrates: The invertebrate fauna collected at the Cut Bank Creek site suggests excellent water quality, and a thermal regime appropriate to a plains river. Instream habitats appeared to be somewhat monotonous but intact. ¾ Periphyton: The diatom metrics indicate minor impairment, but good biological integrity with full support of aquatic life uses, when compared to criteria for prairie streams. Environmental stress was the cause of the minor impairment, possibly the result of elevated dissolved solids or depressed dissolved oxygen. When compared to mountain streams criteria, minor impairment is indicated due to elevated organic nitrogen.

12 4.3 Marias River

¾ Water Chemistry: The Marias River at all sampling sites show small concentrations and low variability of all tested elements, both temporally and spatially, especially during low flows. There are a few notable exceptions when the flows were high. o The upper Marias River above Lake Elwell during high flow events show elevated sediment and phosphorus levels. These concentrations can be 3 to 5 times higher at the F Bridge than at the Interstate 15 Bridge near Shelby. The river is evidently picking up a large amount of sediment from valley wall sloughing, active bank erosion, and inputs from the Dry Fork. The following are examples of high flows influences on TSS and phosphorus levels, and how Lake Elwell serves as a buffer for the downstream reach. There are also significantly lower TP and TSS spatial changes below Lake Elwell than above for comparable flows. This is likely attributable to the upper reach having erodible shale bedrock along the valley margins, more active channel meandering, versus less erodible sandstone and limited channel change on much of the lower reach.

Date Flow Location Total Total Suspended Phosphorus Sediment October 220 cfs I-15 Bridge .008 mg/l 31 mg/l 2006 F Bridge .006 mg/l 18 mg/l Lake Elwell 521 cfs Below Tiber .007 mg/l 3 mg/l Dam Loma Bridge .002 mg/l 11 mg/l

March 2007 840 cfs I-15 Bridge .205 mg/l 310 mg/l F Bridge .748 mg/l 1720 mg/l Lake Elwell 940 cfs Below Tiber .013 mg/l 3 mg/l Dam Loma Bridge .050 mg/l 75 mg/l

Specific Conductivity (SC) has been recorded at the USGS Shelby Gaging Station since 1980. The data shows that at flows less than 1,500 cfs, most SC values ranged between 400 and 800 mmhos/cm; above 1,500 cfs, the average SC values slowly decline as flow increases, typically ranging between 200 and 400 mmhos/cm.

¾ Aquatic Invertebrates: Aquatic invertebrates were collected in August 2005. Analysis shows that filamentous algae may have provided the dominant instream habitat at the upper most site (MR-21 @ I-15 Bridge). Still, water quality was good and the thermal regime appropriate. Diverse instream habitats, good water quality, and an appropriate thermal regime are implied by the fauna collected at MR-36 @ F Bridge. Cool water temperatures characterized the site below Tiber Dam (MR-43 @ USGS Gaging Station), but instream habitats appear to have been limited there. Finally, there was evidence of nutrient enrichment discerned in the fauna collected at the Circle Bridge (MR-58).

13 ¾ Periphyton: At Site MR-21 (I-15 Bridge), diatom metrics indicated an unimpaired condition, with excellent biological integrity indicating full support of aquatic life uses. The second site (MR-36) had good biological integrity, with minor impairment, indicated by a slightly depressed diversity index value and an elevated disturbance index value. The conclusions stated above are based upon prairie stream criteria. Immediately below Tiber Dam at Site MR-43, the periphyton community indicated only minor impairment, with good biological integrity and full aquatic life use support based upon mountain stream criteria. The fourth Marias River site at the Circle Bridge was unimpaired, with excellent biological integrity and full support of aquatic life uses. ¾ Mussels: Shells of mussels were periodically found along the banks of the Marias River, mostly below Tiber Dam. Mussel species included Fatmucket and/or Giant Floater. These species are thought to be sensitive to long-term disturbance and polluted water. Even though there was not a quantified sampling of mussels taken along the Marias River, their presence can be an indicator of low disturbance and good water quality.

4.4 Teton River

¾ Water Chemistry: Samples were taken two different times: March 2006 and March 2007. TSS (66 mg/l vs. 326 mg/l) and Total Phosphorus (.039 mg/l vs .186 mg/l) concentrations increased by 5 times from a flow of 50 cfs and 102 cfs respectively. A sediment plume coming into the Marias was observed during the March 2007 sampling. The lower flow of 50 cfs showed higher concentrations of inorganics, nitrogen, and dissolved metals. The Teton River Watershed group has an arrangement with USGS to measure flow, TSS, SC, and Water Temperature periodically since 1998 at this site. Their data shows that flow is closely correlated to TSS. For a comparable flow, the Teton River has far more suspended sediment than the lower Marias River. During this period, concentrations of dissolved solids have been measured as high as 1500 micosimens/cm. The higher values tend to be read during very low flow events, however there does not appear to be definitive correlation between dissolved solids and flow.

4.5 Additional Water Quality Information

¾ PH: PH field readings showed a narrow range of 7 to 8. These values are common for these types of streams. ¾ Specific Conductivity (SC): SC values (index of dissolved solids) for most sample sites were very low, commonly less than 1 mmho/cm. The only exceptions were lower Cut Bank Creek and the Teton River whose SC values consistently ranged from 1 to 2 mmhos/cm. Pondera Coulee also showed SC values between 1 and 2 mmhos\cm during non-flow periods, but usually dropped to less that 1 mmho/cm during periods of flow. ¾ Water Temperature: Water temperature is dependent upon a number of factors: ambient air temperature, time of year, riparian shading, dewatering, etc. Water temperatures recorded are in the normal range for what is typically seen with prairie streams. The one major departure is directly below Tiber Dam where there are cold water releases from Lake Elwell. For nearly 20 miles downstream from Tiber Dam, the Marias River is much colder than before the dam was built. It is cold enough to sustain an isolated cold water fishery.

Lab analysis sheets are available at the Liberty County Conservation District Office.

14 5. Marias River Reach Summaries

16 Reach # 1

Assessment Sites: MR-1 through MR-7

Reach Description: Confluence of the Two Medicine River and Cut Bank Creek (Sullivan Bridge) to Willow Rounds.

Cut Bank Creek (right) and Two Medicine River (left) combine to form the Marias Ri

Channel Type: The valley width is relatively narrow (avg. 1700 feet) for the first two river miles of the Marias River below the Sullivan Bridge due to relatively hard, nonmarine Two Medicine Formation sandstone and mudstone. Because of the narrow valley, the river channel runs mostly straight with a low sinuosity of 1.1 and a channel gradient of over 14 feet/mile. The valley wall geology transitions briefly into a marine mudstone/sandstone (Virgelle Formation: Telegraph Creek Formation) as the river approaches Willow Rounds, then into to a softer, more erodible marine shale (Marias River Shale: Kevin Member). The valley becomes much wider (average 3000 feet; up to 5,000 feet at Willow Rounds) due to these erodible formations. The river has more mid-channel islands and an increased sinuosity of 1.6. The channel gradient flattens out to 5 feet/mile at Willow Rounds

Two Medicine Formation: Site MR-2 Marias River Shale: Site MR-6

17 The material making up the point bars and channel bottom is primarily small gravels; however, silt and sediment become increasingly evident as you move downstream. The rise in silt is derived from the highly erodible shale valley walls and in-channel erosion. The fall in channel gradient also causes an increase in silt deposition on the river bed.

Near the downstream end of Reach #1, there are several river meanders that have recently breached (avulsions), probably during the 1964 or 1975 flood events.

Riparian Plant Community: Dominant Plant Community: The dominant overstory tree is narrowleaf cottonwood. Plains cottonwood and peachleaf willow are much less common. Most sites have a diversity and abundance of understory species that include: woods rose, snowberry, western white clematis, golden currant, sandbar willow, silverberry, silver buffaloberry, and yellow willow.

Riparian Condition: Riparian scores were generally very good, ranging from 75 to 87. One exception is a riparian site that was rated at 68, reflecting heavier livestock use along the river. Most riparian plants showed good age diversity, especially narrowleaf cottonwood on the point bars and low floodplain.

Riparian Extent: Comparing the 2005 aerial photography with 1941 aerial photography, the extent of the riparian forest in this reach has not changed significantly over the last 65 years.

Riparian Disturbance: Beaver activity is relatively high at Site MR-6 along the abandoned river channel now serving as an irrigation conveyance ditch. A 100 foot wide band of trees next to the ditch/channel has been dropped by beaver. Beaver impacts are isolated and normally affect small patches of riparian forest.

Band of riparian forest at Willow Rounds impacted by beaver.

18 Noxious Weeds/Invasive Plants Infestations: Spotted knapweed (abundant) Houndstongue (occasional) Leafy spurge (occasional – few small scattered patches) Canada thistle (occasional patches) Bull thistle (sporadic) Russian olive (very sporadic)

Infrastructure: Sullivan Bridge: The north side road approach to the Sullivan Bridge is cut into the valley wall along Cut Bank Creek, several hundred yards above its confluence with the Two Medicine River. Maintaining this section of road has been an on-going challenge because of unstable slopes and the sloughing of material off the bluff on to the road. Compounding the problem is the placement of the bridge: the north approach is placed at a sharp angle to the bridge making it difficult for larger vehicles to navigate the turn. The south road approach also prevents the historic access of high flows on to the floodplain, now forcing all high water events to pass under the Sullivan Bridge.

Sullivan Bridge looking north.

Sullivan Bridge Access Site: The public access site upstream from the Sullivan Bridge is undeveloped and has been heavily impacted by off-road vehicle use, camp fires, and trash. This site is administered by the Bureau of Land Management.

Irrigation Pumps: The valley bottom is a mosaic of fields and riparian forest. Many of the fields are irrigated using either wheel lines or small pivots with irrigation pumps located on the river’s edge. Most of the pumps are portable and are likely moved off the river after the irrigation season.

Irrigation Headgate - Willow Rounds: At Site MR-6, an abandoned river channel serves as an irrigation conveyance. A small headgate and channel plug have been installed at the upstream end of the old channel to control in-flow from the river. Water is able to enter the converted channel only during higher flows.

20 Reach #2

Assessment Sites: MR-7 through MR-17

Reach Description: Willow Rounds to the Marias Valley Golf Course.

Marias River looking downstream from the north valley rim near the old Lincoln Ranch buildings. The channel is highly mobile along this section of river.

Channel Type: The valley wall geology is a continuation of the soft, erodible marine shale that emerged in the lower end of Reach #1. This geologic formation called the Kevin Member of the Marias River Shale consists primarily of dark-gray shale. It is often associated with large valley wall slumps. The valley width ranges between 5,400 feet to 2,300 feet (average 3,900 feet) with a sinuosity of 1.6. Following the historic 1964 flood, the channel cut through several meanders causing the river to lose a significant amount of channel length. Over the last 43 years, the river has begun to reestablish sinuosity and increase channel length. This is reflected by the active bank erosion occurring throughout the reach. Bank erosion is a natural response of a river seeking to increase channel length and move toward stability.

1941: Upper end of Reach #2. 2005: Same location showing how the river has made a major shift to the north.

21 A unique feature at Site MR-8 is a small “island ridge” of shale outcrop located in the middle of the valley bottom. The main river channel flowed south of the outcrop prior to the1964 flood. During the flood, the river shifted to the north of the outcrop cutting nearly a mile of new channel across the floodplain.

Silt content on the point bars and the channel bottom continues to increase. Much of this material enters the river from the shale valley wall where the river butts up against it and from active bank erosion as the river attempts to regain channel length lost during the 1964 flood. The valley gradient is relatively flat in this reach at 5.6 feet per mile.

Riparian Plant Community: Dominant Plant Community: Narrowleaf cottonwood is the dominate overstory tree with young plains cottonwood saplings and sandbar willow commonly found on gravel point bars. The under-story shrubs include common chokecherry, serviceberry, water birch, yellow willow, silver buffaloberry, and sandbar willow. Species occurrence and density vary by site.

Riparian Condition: Riparian scores ranged from 63 to 83. The lower range of scores came from small holding pastures located near ranch buildings or where continuous summer grazing occurs. The river commonly serves as the primary source of livestock water. It is difficult to manage livestock in a relatively narrow river valley. Special grazing measures are usually needed to minimize livestock impacts.

Riparian Extent: The riparian forest has been reduced slightly (< 5%) since 1941 due to agricultural development. Historically, this reach has had a limited amount of agricultural development as the river channel readily shifts from one side of the valley to the other during high flow events. Riparian forest clearing has occurred on the lower end of the reach.

Noxious Weed/Invasive Plant Infestations: Spotted knapweed (abundant, mostly on the higher terraces) Russian knapweed (occasional) Leafy spurge (patches becoming increasingly larger and more common) Canada thistle (occasional patches) Russian olive (sporadic plants)

22 Leafy spurge patches become larger and more common as you move downstream.

Infrastructure: Bank Stabilization: There is one bank stabilization project along this reach. It was recently constructed at Site MR-15. The project included bank shaping and rock rip- rap. The apparent reason for this work was to keep the river from migrating into an old meander bend and to protect downstream farmland. In 2005, the landowner had additional work to complete before the project was finished.

Shaped bank on outside bend. Additional work is planned to protect the eroded bank toe.

Irrigation Pumps: There is a limited amount of irrigation within the river valley. The only large system is a center pivot sprinkler located at Site MR-16. A few older pump sites were noted along the reach, but most appeared to no longer be in use.

24 Reach #3

Assessment Sites: MR-17 through MR-32

Reach Description: Marias Valley Golf Course to Naismith

Looking east from the Marias Valley Golf Course toward I-15 and Williamson Park.

Channel Type: The valley wall geology is a continuation of the soft, erodible marine shale (Kevin Member of the Marias River Shale). Sloughing of the valley wall is often associated with this geologic formation. A mantle of glacial deposit can be seen as a thin, lighter-colored layer on top of the shale. The average valley width is 2,900 feet with a highly sinuous river channel measuring 1.7. The channel gradient is 3.8 feet per mile, lower than the previous reach.

Between the Marias Valley Golf Course (Site MR-18) and Williamson Park (Site MR-23), the river has a high density of bank armoring and channel manipulation including:

1) A 1,400 foot long floodplain dike and bank stabilization project that includes bank shaping, jute fabric matting, root wads, and small rock flow deflectors. This

25 project was constructed over 5 years ago along the south side of the Marias Valley Golf Course. Both the dike and bank stabilization project were sited between the active river channel and the golf course blocking off an old river meander. There is also an older section of rock rip-rap upstream along the west boundary of the golf course that is over 1,000 feet long.

2) 1,800 feet of rock rip-rap that lines the west side of the I-15 Right of Way (Site MR-19) culminating with a 15 foot high flow deflector next to the south abutment of the I-15 Bridge. Rock rip-rap was also installed to prevent scouring on both I- 15 bridge abutments.

3) Rock rip-rap has been installed approximately 800 feet downstream from the I-15 Bridge on the north bank. This bank stabilization was probably needed because of the high water “chute effect” through the bridge directing high energy flows into the river bank.

4) The river was straightened when a large meander was intentionally cut-off in the early 1960s to protect city wells located downstream from Site MR-22.

5) Bank stabilization measures were installed along Williamson Park about 5 years ago that included bank shaping and jute matting. This project is similar to the one completed at the golf course.

The river has become “hamstrung” in this reach contributing to accelerated bank erosion in a number of locations. Approximately 200 feet of erosion is threatening the I-15 R/W (upstream end of Site MR-19). Over ¼ mile downstream from the I-15 crossing (Site MR-22), there is a 12-15 foot high eroding bank that has exposed cables and is threatening a subdivision access road. And, across from Williamson Park, the river is actively migrating into an adjacent field.

Since 1940, active channel migration is common on the lower end of Reach #3, especially where the BNSF railroad enters the valley.

26 Upper Reach #3: 1941. Highly sinuous channel before the Marias Valley Golf Course and I-15 were built.

Upper Reach #3: 2005. Note the straightened channel both upstream and downstream of the I-15 crossing.

Site MR-18 Site MR-20 Site MR-22

Riparian Plant Community: Dominant Plant Community: Narrowleaf cottonwood remains the dominate overstory tree with an increasing presence of plains cottonwood. The under-story shrubs include common chokecherry, western white clematis, serviceberry, water birch, yellow willow, silver buffaloberry, and sandbar willow. Species occurrence and density vary by site.

27 Riparian Condition: Riparian assessment scores were tightly grouped between 68 and 71. The major factors that brought the scores down were the heavy infestations of noxious weeds and invasive plants.

Noxious Weeds: Leafy spurge on the lower end of the reach is being grazed by sheep, but leafy spurge control is limited. Weed densities are high and difficult to control. Some landowners are participating in an herbicide and insect release program as a containment strategy.

Riparian Extent: A few patches of riparian forest have been cleared over the last 65 years reflected by the development of the Marias Valley Golf Course and a large hay field located across the river from Williamson Park. On the middle and lower sections of this reach, most of the existing fields were also present in 1940 as either dryland or flood irrigated fields. Since 1940, many of these fields have had center pivot sprinklers installed. Even though the river does not shift around like it does upstream of I-15, there is some subtle channel movement with active bank erosion eating into the field fringes.

Noxious Weed/Invasive Plant Infestations: Spotted knapweed (abundant) Leafy spurge (abundant along the river; moving up side coulees) Russian knapweed (occasional) Houndstongue (scattered plants) Canada thistle (occasional patches) Russian olive (sporadic plants, slowly increasing in numbers)

Infrastructure: Bank Stabilization: There are several bank stabilization sites above and below the I- 15 crossing. The bioengineered sites adjacent to the Marias Valley Golf Course and Williamson Park were completed within the last 5 to 10 years that included bank shaping, jute matting, and small flow deflectors. Blanket rock rip-rap was used on three different sites: the west edge of the Marias Valley Golf Course, the west side of the I-15 R/W south approach, and an outside bend approximately 750 feet downstream from the I-15 crossing. The rock rip-rap at these sites appears to have been constructed over 30 years ago.

I-15 Interstate Highway and old Highway 91 Bridges: This series of three bridges creates a significant floodplain restriction that is directly contributing to upstream and downstream stream bank instability.

USGS Gaging Station: An active USGS gaging station is located on the north bank, approximately 20 feet downstream from the old Highway 91 Bridge. The station’s official designation is: 06099500 Marias River near Shelby MT (USGS 2006). It has provided discharge data since 1902 and water quality data (specific conductance, water temperature, and air temperature) since 1980.

Center pivot located at Site MR-28. Note the leafy spurge creeping into the field.

Irrigation Pumps: Irrigated fields have been developed on the middle and lower sections of this reach, downstream from Williamson Park. Most of these fields are sprinkle irrigated, supplied with water from the Marias River via portable pumps.

Old Dump: An old solid waste site is located on a side coulee north of Williamson Park. Material in this dump could potentially be detrimental to water quality, both on-site and off-site.

Gravel Pit: A large gravel pit is situated on the south bench overlooking Site MR-25. Material from the gravel pit is drifting down the bluff into the river.

30 Reach #4

Assessment Sites: MR-32 through MR-40

Reach Description: Naismith to Lake Elwell

Channel Type: The valley wall geology is a continuation of the soft, dark-gray marine shale (Kevin Member of the Marias River Shale). A mantle of glacial deposit can be seen as a lighter-colored layer on top of the shale. Similar to reach #3, the valley width remains wide (average 2,900 feet) with a sinuosity of 1.8. The channel gradient has lessened to 2.6 feet per mile.

Little channel migration has occurred since 1940. One exception is a large meander avulsion (Site MR-35) downstream from the old Fort Conrad site which took place sometime within the last 10 years. Over one mile of river channel was lost. Many of the outside bends are actively eroding, but not at an unusually high rate.

Site MR-33: River has eroded into this field Site MR-35: The river has recently cut through nearly 150 feet over the last 65 years. a channel meander creating the loss of over one mile of river channel.

The elevated approaches leading to the BNSF Railroad Trestle (Site MR-34) and the F Bridge (downstream from Site MR-36) restrict high water access to the floodplain. Out-of-bank flow events are forced to funnel under these structures rather then spread out on to the adjacent floodplain. The “chute effect” through these crossings contributes to accelerated bank erosion as much as one mile downstream of each crossing.

The river channel below the F Bridge tends to shift around more than the upper end of this reach. High pool levels and sediment deposition in upper Lake Elwell create a backwater effect that causes the upstream river channel to migrate back and forth more than normal.

31 Riparian Plant Community: Dominant Plant Community: Narrowleaf cottonwood remains the dominate overstory tree with increasing numbers of plains cottonwood. The native under-story shrubs include: peachleaf willow, common chokecherry, golden currant, western white clematis, inland gooseberry, red-osier dogwood, yellow willow, woods rose, western snowberry, and sandbar willow. Species occurrence and density vary by site.

Riparian Condition: Riparian assessment scores ranged between 71 and 85. The higher riparian scores were typically found downstream of the F Bridge. The middle section of Reach #4, Naismith to the F Bridge, was not scored, however the river bottom does show heavy livestock use and potentially long-term impacts on the sustainability of the riparian plant community. Older shrubs are being “highlined” by browsing livestock. Younger shrubs have a difficult time surviving. Sheep are used to graze this part of the river for leafy spurge control.

Beaver: There is occasional evidence of current and past beaver presence. The overall impacts on the riparian vegetation are isolated and relatively minor.

Riparian Extent: A slight reduction in the amount of riparian forest has occurred over the last 65 years. Prior to the 1940s, patches of riparian forests were cleared for agricultural development, primarily between Naismith and the F Bridge.

Noxious Weeds: An integrated weed management approach is being aggressively implemented by the Toole County Weed District, the Bureau of Reclamation, and several of the landowners. Above the F Bridge, sheep have been used extensively to graze leafy spurge. This effort is augmented by ground-based herbicide applications and insect releases in the valley bottom and helicopter spraying on the adjacent hillsides and coulees. Leafy spurge control in this reach is realistically approached as more of a containment strategy rather than an eradication effort.

Looking east from the valley bluff north of Fort Conrad. The yellow patches are leafy spurge.

32 Noxious Weed/Invasive Plant Infestations: Spotted knapweed (common) Leafy spurge (abundant along the river; moving up valley wall coulees) Russian knapweed (common) Houndstongue (scattered plants) Canada thistle (occasional patches) Russian olive (low density)

Infrastructure: BNSF Trestle and the F Bridge: These crossings and road approaches create floodplain barriers that force all flows to pass under the crossings. There is old rock rip-rap above the BNSF trestle (east bank) and relatively new rock rip-rap upstream from the F Bridge (west bank).

Irrigation: There are several fields being irrigated along this reach, primarily with portable pumps and wheel line sprinklers.

36 Reach #5 through #7

Assessment Sites: None

Reach Description: Lake Elwell to Tiber Dam

General Description: Geology: The upper end of Lake Elwell is bordered by the Kevin Member of the Marias River Formation. A geologic change occurs where the Willow Creek Arm joins the main reservoir. The geology transitions into a younger non-marine Telegraph Creek Formation; a relatively thin (150 feet) layer interbedded with sandy shale and sandstone. The eastern reservoir margins have varied depths of glacial deposits lying on top of the bedrock.

Since their completion in 1956, Tiber Dam and Lake Elwell have served important functions in flood control, fish and wildlife, and municipal and industrial water supplies. Lake Elwell was named for Judge Charles B. Elwell (1888-1974), former director of the Montana Reclamation Association. Lake Elwell covers 14,842 surface acres with 149 miles of shoreline and a maximum depth of 140 feet. These statistics are relative to the elevation of the pool level in the reservoir.

Lake Elwell has a storage capacity of 1,368,157 acre-feet; 389,695 acre-feet of this capacity is allocated to active conservation and 400,838 acre-feet toward flood control for the lower Marias River and to assist in flood control of the Missouri River (BOR DataWeb). Rocky Boy’s North Central Montana Regional Water System has started construction on a regional water system that will pump water out of Lake Elwell eventually delivering it to the Rocky Boy’s Reservation (10,000 acre-feet) with additional water for several other off-reservation public water systems.

Five private irrigators and the Tiber Irrigation Co. (17 users) are pumping water from Lake Elwell under long-term service contracts. The maximum amount of water diverted per year is about 6,000 acre-feet.

Center pivot sprinkler supplied by Lake Busy boat ramp near the Tiber Marina Elwell water. on the northeastern end of the lake.

37 Tiber Dam is an earthfill structure containing 9.8 million cubic yards of embankment materials. The dam has a crest length of 4,300 feet, and a structural height of 211 feet. There is an earthfill dike on the south rim of the reservoir near the dam that is 16,650 feet long (BOR DataWeb).

There is a four year fisheries study on-going in the Upper Missouri River Basin that includes the Marias River. The Bureau of Reclamation is studying the response of pallid sturgeon to simulated high water releases. A spring rise has not occurred on the lower Marias River in a number of years due to the prolonged drought. In June 2006, a short-term release from Lake Elwell was carried out to mimic a natural spring rise. Because of low run-off and inadequate reservoir water, a simulated spring rise in 2007 did not occur.

1940: Prior to Tiber Dam construction.

2005: 50 years after Tiber Dam construction.

38 Riparian Plant Community: Noxious Weeds: An aggressive weed management program is being waged against noxious weeds along the reservoir fringes by the Bureau of Reclamation. The main weed being targeted is leafy spurge. This is an important management program not only for the Bureau, but for all landowners downstream. Lake Elwell serves as an effective buffer to the downstream spread of leafy spurge.

Riparian Forest: The riparian forest that once bordered the Marias River, now inundated by Lake Elwell, is essentially gone. The values associated with the pre- dam Marias River corridor have been replaced by values attributed to Tiber Dam and Lake Elwell.

40 Reach #8

Assessment Sites: MR-41 through MR-47

Reach Description: Tiber Dam to Pugsley Bridge

Channel Type: The valley wall geology is mostly non-marine Telegraph Creek Formation, an interbedded brownish gray shale and fine-grained sandstone. Total formation thickness averages about 150 feet. At the lower flanks of the valley wall, the older Kevin Member of the Marias River Formation (darker shale) is exposed underlying the Telegraph Creek Formation. A mantle of glacial deposit can be seen as a lighter- colored layer on top of the shale/sandstone. The valley width averages about 2,500 feet with a channel sinuosity of 1.5 and channel gradient of 4.4 feet per mile.

The channel patterns in the 1940 photography show little change when compared with the 2005 photography. A notable exception is the river channel directly below Tiber Dam. In this one mile section, the river was highly manipulated during the construction of the dam. Several small mid-channel islands were formed and still exist between the dam and Sanford Park. There was approximately 2,000 feet of rock rip-rap installed along the north bank protecting an access road and an in-channel rock weir constructed in 2004 to mix the cold water coming out of the river outlet with warmer water being discharged from the auxiliary outlet during high flows.

Site MR-41: Braided channel downstream from Tiber Dam. Sanford Park is located downstream on the left side of river. There are moderate to high densities of Russian olive for the first mile of river.

41 Rock weir below Tiber Dam that mixes cold water from the river outlet with warm water coming out of the auxiliary outlet during high flows.

The river flows below Tiber are fairly constant throughout the year, ranging between 400 and 600 cfs. The natural low and high peaks have been truncated resulting in less downstream channel migration or active bank erosion. Most of this reach is a single threaded channel with sections of vertical entrenchment especially on the straighter sections. Channel entrenchment is a natural response of the river due to the major alterations in the natural hydrology and sediment load below Tiber Dam. Because of the channel entrenchment and infrequent high flows, the historic floodplain is seldom accessed by flood water.

Riparian Plant Community: Dominant Plant Community: This is a transitional reach where narrowleaf cottonwood and plains cottonwood both dominate the overstory within the riparian zone. Narrowleaf cottonwood has an advantage for long-term reproduction due to its ability to produce by both air-borne seed and underground sprouts. Plains cottonwood is limited to reproducing from seed on open point bars and freshly deposited sediment. Given the infrequent occurrence of high-water scouring flows below Tiber Dam, the seedbed conditions necessary for plains cottonwood seedlings are considerably reduced compared to pre-dam conditions. The native under-story shrubs include peachleaf willow, chokecherry, silver buffaloberry, golden currant, red-osier dogwood, yellow willow, woods rose, western snowberry, and sandbar willow. Species occurrence and density vary by site.

Riparian Extent: The extent of the riparian forest in Reach #8 has not changed significantly over the last 65 years.

Beaver: Beaver bank lodges are common along this reach; however the riparian vegetation shows only isolated impacts. Beaver populations may have increased following construction of Tiber Dam because safe den sites are usually more abundant along banks that experience minimal water level fluctuations. Frequent

42 high flows that are part of a natural flood cycle are a major cause of beaver mortality and den abandonment (Lesica, 1999).

Riparian Condition: Riparian assessment scores ranged between 71 and 85. Generally, the condition of the riparian vegetation along this reach was very good. The scores would be higher if conditions were more conducive to plains cottonwood regeneration.

Noxious Weeds: The Bureau of Reclamation (BOR) and the Pugsley Ranch carry on an aggressive integrated weed management program along this reach. They attack noxious weeds with both ground-based herbicide applications and occasionally insect releases targeting leafy spurge. Unlike the Marias River above Lake Elwell, weed control is approached as an eradication strategy rather than containment because of the relatively low weed density.

Invasive Species: Russian olive has a moderate to high density infestation in the first mile below Tiber Dam, mostly on the BOR managed lands. The mature windbreak of Russian olive at Sanford Park is a major source of seed for the lower Marias River. After the first mile, Reach #8 experiences low densities of Russian olive that are single, sporadic plants along the river’s edge and low floodplain. Local residents say they first saw Russian olive plants along the river about 25 years ago.

Noxious Weed/Invasive Plant Infestations: Spotted knapweed (occasional plants) Leafy spurge (low density; few small patches upstream from Pugsley Bridge) Russian knapweed (occasional plants) Houndstongue (common) Canada thistle (common) Russian olive (Abundant below Tiber Dam; low density further down) Whitetop (small patch)

Infrastructure: Fish Habitat Structures: There are several small rock cribs in the river channel between Sanford Park (MR-42) and the USGS Gaging Station (MR-43) intended to serve as fish habitat structures. Some have eye bolts to which brush bundles were once attached.

Small rock crib structures intended to create fish habit.

43 USGS Gaging Station: An active USGS gaging station is located on the north bank, approximately 2 miles downstream from Tiber Dam. The station’s official designation is: 06101500 Marias River near Chester MT (USGS 2006). The station has provided discharge data sporadically from 1921 to 1955. Then, from 1955 to the present, the discharge data is continuous. Water quality data that includes biological, nutrients, inorganics, sediment, radiochemicals, and physical, properties have been collected at various times since 1964.

Irrigation Pumps: There are four irrigation pumps along this reach: three privately operated and a portable pump near Sanford Park operated by the Bureau of Reclamation (BOR/FW&P 2007).

BOR pump site near Sanford Park. Pump site between MR-45 and MR-46.

Pugsley Bridge’s North Abutment: There is at least 1,000 feet of active bank erosion immediately downstream from the Pugsley Bridge’s north abutment. This erosion is exacerbated by the encroachment of the bridge’s north abutment into the main river channel. This abutment creates a downstream backwater eddy that eats into the north bank. There is a mid-channel island below the bridge that is also pushing the main flow of the river against this same bank. If the bank continues to erode, the integrity of the north bridge abutment and the county road approach could become threatened.

Pugsley Bridge north abutment. Downstream erosion on north bank.

45 Reach #9

Assessment Sites: MR-47 through MR-59

Reach Description: Pugsley Bridge to Circle Bridge

Channel Type: Geology: From Pugsley Bridge to the Moffat Bridge, both sides of the valley walls consist of Telegraph Creek Formation (an interbedded shale and fine-grained sandstone). Below the Moffat Bridge, the younger Eagle Sandstone begins to emerge on the north valley wall as the river nears the Circle Bridge. The Eagle Sandstone (Virgelle Member) is a thick-bedded to massive sandstone that forms rounded rims and bluffs. The south valley geology below the Moffat Bridge continues as the Telegraph Creek shale with large deposits (10 to 20 feet thick) of old alluvium (gravel and sand) on the upper bench. There are two gravel pits located west and east of the Moffat Bridge where gravel is mined from these alluvial deposits.

River Channel: The average valley width is 3,900 feet with a channel sinuosity of 1.5 between the Pugsley Bridge and the Moffat Bridge, then increases to 1.8 from the Moffat Bridge to the Circle Bridge. Most of this reach is a single threaded channel with intermittent vertical entrenchment. Channel entrenchment is likely a response to changes in the natural hydrology and a lack of sediment load after the construction of Tiber Dam.

The river channel has not changed significantly over the last 65 years; however the valley bottom has old oxbow scars indicating that the river was more dynamic prior to 1940. Since 1956, Tiber Dam has buffered the lower Marias River from large flood events significantly reducing channel movement.

Channel Substrate: Due to infrequent flushing flows and a flat channel gradient (3.6 feet/mile), additional silt coats the channel bottom, especially downstream from the Moffat Bridge.

Meander Avulsion: Approximately 1200 feet upstream of the Circle Bridge, a large channel meander is close to being breached. There is an “isthmus” that measures about 170 feet wide. In 1940, this same site had over 420 feet of land separating the channels. The rate of erosion has slowed in the last 50 years because of reduced flows out of Tiber Dam. However, when this “isthmus” does eventually erode through, approximately 6600 feet of river channel will become abandoned.

Channel meander cut-off (avulsion), upstream from the Circle Bridge, is imminent.

Riparian Plant Community: Dominant Plant Community: The overstory trees found along this reach are narrowleaf cottonwood, plains cottonwood, and peachleaf willow. Narrowleaf cottonwood is the dominant tree because of its ability to produce by air-borne seed and underground sprouts. Plains cottonwood is limited to reproducing from seed on open point bars and freshly deposited sediment. Several mature trees found on the high floodplain are plains cottonwood. The majority of younger trees are narrowleaf cottonwood, most are sprouts produced from older trees. The infrequent high-water flows caused by Tiber Dam limit plains cottonwood reproduction allowing narrowleaf cottonwood to become dominant. There are some cottonwoods along this reach with dead tops. This is a likely response to the extended drought in the region. Common native under-story shrubs include silver buffaloberry, golden currant, yellow willow, common chokecherry, wild rose, western snowberry, and sandbar willow. Species occurrence and density vary by site.

Riparian Extent: The extent of the riparian forest in Reach #9 has changed over the last 65 years. Two to three hundred acres of riparian forest have been cleared since 1940. Several fields were developed for irrigation (flood and sprinkler). Many of these fields either do not have a riparian buffer or have only a narrow riparian band between the field and active channel.

Riparian Condition: Riparian assessment scores were generally very good between the Pugsley Bridge and the Moffat Bridge. The scores ranged from 68 to 87. The upper half of Reach #9 is lightly to moderately grazed by livestock during the fall and winter. Below the Moffat Bridge, the scores dipped slightly, ranging from 62 to 70. The riparian zone on this reach receives heavy pressure from grazing and browse. Many of the river pastures appear to be used during the summer months.

Beaver: Beaver are fairly common along this reach. Several bank lodges were seen. Overall, damage by beaver to the riparian vegetation is isolated and relatively light.

47 Beaver Lodge: Beaver numbers are high along the Marias River below Tiber Dam.

Invasive Species: The occurrence of Russian olive increases from upstream reaches, however the Russian olive infestations are still sporadic. Most infestations are isolated plants along the river’s edge and adjacent floodplain/terraces.

Noxious Weeds: There is an aggressive weed management program along this reach by landowners. Liberty County Weed District provides contracted services to some of the larger landowners. Spotted knapweed is the biggest concern. Leafy spurge and Russian knapweed infestations, though not as common, are treated when found.

Noxious Weed/Invasive Plant Infestations: Spotted knapweed (common) Leafy spurge (low density; isolated patches) Russian knapweed (occasional plants) Houndstongue (common) Canada thistle (common) Russian olive (low density; isolated plants)

Infrastructure: Irrigation Pumps: The number and density of pumps on the river greatly increase along this reach compared to upstream. There are portable pumps (3) and permanent pumps (10) of various sizes using Marias River water. Most are irrigation pumps delivering water to adjacent cropland (combination of flood and sprinkler irrigation), but there are others that provide domestic water to homes/farmsteads in the valley and several miles away. The Riverview Hutterite Colony has a public water system using an infiltration collection system located near the Moffat Bridge. Water is pumped seven miles south of the river to the Colony serving approximately 130 residents.

48 Four pumping stations upstream from the Moffat Bridge on the south bank providing irrigation, stock, and domestic water to landowners located several miles south of the Marias River.

South Chester Water District Pump: A large pumping station near Site MR-54 delivers water to the South Chester County Water District that serves approximately 100 people residing at 25 scattered farmsteads in Liberty County. This pump plant has a well connected to two horizontal perforated pipes that extend into the channel bottom alluvium (South Chester Water Users Association 2001).

Pump Station for the South Chester County Water District.

Corrals/Pens: There are three sites where corrals or pens are located next to the river. These are relatively small livestock concentration areas, but they may be contributing surges of nutrients and sediment into the river during storm or run-off events.

Junk Piles: On the lower end of the reach, there are a few small junk piles situated on the bank of the river. Most of the material includes baling wire, twine, old boards, and miscellaneous metal waste.

River Crossings: Both the Moffat and Circle Bridges (and their road approaches) restrict high water access to the downstream floodplains. Circle Bridge does not have a significant impact on the river because of an adequate span and site location. The Moffat Bridge, on the other hand, has a large mid-channel gravel bar that has formed upstream of the bridge. These gravel deposits are caused by the flow restriction from

49 an undersized bridge span and the north road encroachment that essentially serve as a dike preventing high water from accessing the historic floodplain.

The Moffat Bridge’s north approach prevents high flows from accessing the floodplain, pushing the river to the south.

51 Reach #10

Assessment Sites: MR-59 through MR-71

Reach Description: Circle Bridge to Old Brinkman Gage Station

Channel Type: Geology: From the Circle Bridge (MR-59) downstream 9 miles, the south valley wall continues as the Telegraph Creek Formation (an interbedded shale and fine-grained sandstone). The north valley wall has transitioned into the thick-bedded, harder Eagle Sandstone with the softer Telegraph Creek shale/sandstone layer exposed at the toe. For the first 4 miles, the valley width averages 4,900 feet with a channel sinuosity of 1.7. Once the Eagle Sandstone begins to dominate both sides of the valley, the valley quickly narrows down to 1,000 feet wide with a much straighter channel sinuosity of 1.1. Several large deposits (10 to 20 feet thick) of old alluvium (gravel and sand) can be found on the upper bench, especially on the north bench downstream from the Circle Bridge. The gravel deposits become fewer and smaller further downstream.

The lower end of Reach #10 is bordered by Eagle Sandstone squeezing the river into a narrow, deep valley.

River Channel: The river channel pattern has changed little over the last 65 years because of Tiber Dam’s buffering of flood events. Subsequently, landowners have not seen the need to install bank stabilization/rock rip-rap along this reach. There is evidence of old oxbow channels formed prior to 1940, but not to the extent seen upstream of the Circle Bridge. Sections of the river that have entrenched vertically 2- 3 feet, but again, less so than upstream. Channel gradient averages 3.4 feet per mile.

52 Riparian Plant Community: Dominant Plant Community: The overstory trees found along this reach are plains cottonwood, peachleaf willow, and narrowleaf cottonwood. Plains cottonwood is the dominant tree, both as mature trees on the high floodplain and terraces, and as young saplings on the low floodplain along the river. The influence of Tiber Dam on plains cottonwood regeneration appears to be lessening. Common native under-story shrubs include silver buffaloberry, golden currant, yellow willow, chokecherry, gooseberry, woods rose, western white clematis, western snowberry, and sandbar willow. Species occurrence and density vary by site.

Young plains cottonwood growing on the floodplain next to the river.

Riparian Extent: Over the last 65 years, large patches of riparian forest have been cleared on both sides of the river for the first 6 miles downstream from the Circle Bridge. Along this same section of river, over 400 acres of land has been leveled and developed for flood irrigation. The majority of the agricultural development was completed during the 1960s and 1970s. Many of these fields either do not have a riparian buffer or have only a narrow uncultivated strip separating the field from the river. The lower end of Reach #10 has had little riparian clearing or agricultural development, primarily due to the narrow valley and lack of tillable land.

Riparian Condition: Riparian assessment scores were generally good, ranging from 70 to 80. Most of the riparian plant community is lightly to moderately grazed, primarily during the non-summer months. On the lower half of Reach #10, where the valley becomes narrow, the riparian patches are much smaller and more scattered. There is more summer use, but the riparian scores remain high.

Beaver: Beaver are common along the upper half of this reach where there is more woody riparian vegetation; this is less so where the river valley narrows and the riparian woody vegetation becomes sparse. Overall, damage to the riparian vegetation is relatively light and isolated.

53 Invasive Species: The occurrence of Russian olive is sporadic. Russian olive infestations consist of isolated plants or small thickets along the river and adjacent floodplain.

Noxious Weeds: Russian knapweed is the main noxious weed along this reach. Leafy spurge and Spotted knapweed infestations are present, but not nearly as common.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Houndstongue (common) Canada thistle (common) Spotted knapweed (occasional) Leafy spurge (low density; isolated patches) Russian olive (low density; isolated plants)

Russian Knapweed patches are common all along this reach.

Infrastructure: Corrals: There is one small set of corrals located near the river. This livestock concentration area may be contributing periodic surges of nutrients and sediment into the river during storm and run-off events.

Junk Piles: There are two small junk piles on the upper end of the reach located on the bank of the river. Most of the material includes baling wire, twine, old boards, and miscellaneous metal waste.

Irrigation Pumps: There are five irrigation pumps along this reach, four of which are located in the upper six miles. Three low head pump sites deliver water to near-by fields (flood irrigated) in the valley and the other two transport water to large pivot sprinkler systems on the upper benches outside the valley. A couple of the pump headwalls and platforms are in need of repair.

Low head irrigation pump (Site MR-60).

Hay Coulee Water Users Association: There is a large well next to the river that provides domestic/stock/irrigation water to the Hay Coulee Water Users Association. The Association serves 33 residents, north of the river.

Hay Coulee Water Users Association well and pump house (Site MR-65).

56 Reach #11

Assessment Sites: MR-71 through MR-78

Reach Description: Old Brinkman Gage Station to Black Coulee

Channel Type: Geology: The Eagle Sandstone formation borders both sides of the river valley for the entire length of Reach #11. The younger Claggett Shale, periodically exposed on the upper tier of the valley wall, overlays the Eagle Sandstone. The Claggett formation is brownish-gray shale that is more erodible than the Eagle Sandstone. The valley bluffs are more rounded with fewer sandstone outcrops than seen in the lower end of Reach #10. Up to 200 feet of clay-rich glacial moraines, outwash channels, and lake sediments cover the surrounding bluffs. The valley width remains relatively narrow averaging 1,000 feet wide. The river channel continues to be straight with a sinuosity of 1.1.

River Channel: The river channel pattern has made few changes over the last 65 years. This reach has a flat channel gradient of 2.7 feet per mile with several mid- channel islands throughout its length. There isn’t any bank stabilization/rock rip-rap. The probable reasons are that: 1) the river channel does not move around due to infrequent high energy flood flows, 2) there is a limited amount of developed land and infrastructure in the valley that needs protection, and 3) to transport suitable rip- rap material in to the valley would be cost prohibitive.

Flat water and mid-channel islands are common along this reach. This photo was taken at Site MR-74, looking downstream, just before the river bends to the south for the rest of its journey to the Missouri River.

Aquatic Life: Increased numbers of turtles, amphibians, and mussel shells were observed along this reach. The river temperature is warmer than upstream. The cold water coming out of Lake Elwell has warmed up and no longer has as significant effect on the aquatic life. Algae patches and sediment coverage on the channel bottom are more common.

Riparian Plant Community: Dominant Plant Community: Plains cottonwood is the dominant riparian overstory tree with an occasional peachleaf willow tree scattered throughout the riparian zone. Mature cottonwood trees are found on the high floodplain with the younger cottonwood seedlings/saplings along the river’s edge. Survival rates on the young cottonwood seedlings may be low as they are vulnerable to winter ice shearing. As the old cottonwoods reach the end of their lifespan, and with the lack of young cottonwoods to replace them, a long-term decline in cottonwood groves along this reach may occur. Common under-story shrubs include silver buffaloberry, juniper, yellow willow, chokecherry, woods rose, western snowberry, and sandbar willow. Species occurrence and density vary by site.

Mature plains cottonwood trees on the high Young cottonwood seedlings next to the river. floodplain.

Riparian Extent: Patches of riparian vegetation along this reach are relatively small and scattered. Since 1940, small plots of riparian forest have been cleared for agricultural purposes (both irrigated and dryland fields). Cottonwood stands are declining because of past riparian clearing, old age mortality, and limited numbers of replacement seedlings.

Riparian Condition: Riparian assessment scores (62 to 78) range from fair to good. The majority of this reach is grazed by livestock during the summer months except where there are crop or hay fields in the river bottom. With continuous summer livestock use, the browse on the riparian shrubs and trees and hoof trampling of the river bank are more apparent. Some of the more heavily grazed sites show shrubs that have been “highlined”. These are plants browsed up to 5-6’ creating mushroom- shaped plants.

58 Small stands of riparian vegetation are found along this reach. Some shrubs show browse lines 5-6’ high.

Invasive Species: Russian olive infestations range from low to moderate density levels. There is a noticeable increase in the number and size of Russian olives. Infestations come in the form of small “stringers” or thickets that line the bank.

Stringer of Russian olive plants on the lower end of Reach #11.

Noxious Weeds: Russian knapweed is the major noxious weed throughout this reach. Canada thistle is another common noxious weed found.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Canada thistle (occasional) Russian olive (low-moderate density; isolated plants and stringers)

59 Infrastructure: Irrigation Pumps: Four portable irrigation pumps are sited along this reach. During the last 65 years, over 135 acres have been developed for irrigation (pivot and wheel line sprinklers) in the river valley. There is also a partial center pivot on the upper bench using Marias River water. Most of this development is on the lower half of the reach.

Hill County Water District: A large pump/infiltration gallery facility (Site MR-72) operated by the Hill County Water District is one of two sources that provide domestic water to 11 rural water systems (HCWD 2001). There are over 700 hookups that serve 1,700 people living in rural areas and small communities along Highway 2 between Chester and Havre. In early 2008, a major upgrade was initiated to bring the facility into compliance with Montana DEQ standards.

Hill County Water District pump/infiltration gallery facility.

61 Reach #12

Assessment Sites: MR-78 through MR-83

Reach Description: Black Coulee to Sheep Coulee

Channel Type: Geology: The Eagle Sandstone formation borders both sides of the river valley for the entire length of the reach. The older Telegraph Creek formation (sandy shale and thin-bedded sandstone) becomes more exposed at the toe of the valley wall at the lower end. The valley bluffs reflect this geology as a mix of rounded shale hills and sandstone outcrops. The valley width remains relatively narrow averaging 1,100 feet wide with a sinuosity of 1.2.

This photo was taken near Sheep Coulee looking north. Eagle Sandstone restricts the river channel within a narrow valley.

River Channel: The river channel pattern has changed very little over the last 65 years. This reach has the same channel pattern and gradient (2.7 feet/mile) as in the previous reach.

The river runs straight and slow within a narrow valley. This photo was taken near Site MR-81.

Riparian Plant Community: Dominant Plant Community: Plains cottonwood is the dominant riparian overstory tree. Most of the cottonwood trees are middle-aged to fully mature with little age diversity. Young cottonwood seedlings or saplings are rarely seen. Unless conditions change to encourage new cottonwood plants (high energy flows and freshly deposited sediment), there will be a slow decline in the number and size of the cottonwood groves as the cottonwoods reach the end of their lifespan. The native under-story shrubs were few and scattered. They include: Rocky Mountain juniper, western snowberry, and peachleaf willow.

Riparian Extent: The patches of riparian vegetation are relatively small and scattered, although the cottonwood patches tend to get larger further downstream. Very little riparian vegetation has been removed during the last 65 years due to a lack of tillable land and the expense of building all-weather roads into the valley.

Riparian Condition: Riparian assessment scores (70 to 80) were generally good. The scores would have been higher if Russian olive infestations were fewer and if there was more age diversity and seedling replacement potential for the plains cottonwood trees.

63 Invasive Species: Russian olive infestations vary from low to moderate densities. Compared to the upstream reaches, more Russian olives are occupying the floodplain as single plants, small thickets, or “stringers”.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Canada thistle (scattered plants) Russian olive (moderate density: small thickets and stringers)

Russian olive commonly grow along the perimeter of a cottonwood grove. They will grow in the shade of a larger tree, but prefer full sunlight.

Infrastructure: Irrigation Pumps: There are a small number of pumps/wells along this reach used for domestic, stock, and small acreage irrigation. One notable exception is a large pump at Site MR-81 near the mouth of Fourmile Coulee. This pumping station, constructed about 10 years ago, lifts water 300 vertical feet to several center pivots irrigating nearly 1,000 acres on the west bench.

64 Large irrigation headgate on the west side of the river at Site MR-81.

Pipeline delivering irrigation water to center pivots on the west bench.

66 Reach #13

Assessment Sites: MR-83 through MR-86

Reach Description: Sheep Coulee to Old Ranch Buildings

Channel Type: Geology: The lower valley walls are made up of the softer Telegraph Creek formation (sandy shale and thin-bedded sandstone) with the harder Eagle Sandstone overlying the shale. The valley width has become slightly wider, averaging about 1,500 feet mile wide; the river channel sinuosity has increased to 1.3.

Eagle sandstone cliffs overlaying the softer Telegraph Creek shale.

River Channel: The river channel has moved a little over the last 65 years, slightly more than upstream. There are short sections of actively eroding river bank. Many of the point bars are well developed. This reach has a higher channel gradient than the previous two reaches (3.2 feet/mile) with several small mid-channel islands throughout its length. The only bank stabilization is a small section of cobble rip-rap near some old ranch buildings at Site MR-86.

Riparian Plant Community: Dominant Plant Community: Plains cottonwood is the only riparian overstory tree found along this reach. Mature cottonwoods dominate the high floodplain and terraces with sparse understory (western snowberry). Cottonwood seedlings and saplings populate the low floodplain in greater numbers although they may be vulnerable to ice shearing.

Riparian Extent: The patches of riparian vegetation along this reach are larger and more frequent than the previous reach. Over the last 65 years, there has been little overall change in the amount of riparian vegetation.

67 Riparian Condition: Riparian assessment scores (73 to 82) along this reach are good. The majority of the riparian zone is lightly grazed by livestock. A few horses were seen on the river bottom, opposite Sheep Coulee.

Horses grazing valley bottom near Sheep Coulee.

Mature cottonwoods on the high floodplain with little understory.

Invasive Species: Russian olive infestation densities were generally low; mostly scattered plants or small thickets. The occurrence of Russian olive has decreased from that of Reach #12.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Canada thistle (occasional) Russian olive (low-moderate density; isolated plants and stringers)

Infrastructure: Irrigation Pump: There is one irrigation pump on this reach. It is located on the lower end of this reach, immediately downstream from the ranch buildings at MR-86. This pump delivers water to a wheel-line sprinkler system on the west floodplain irrigating approximately 75 acres. Old hay has been dumped over the side of the bank in this same location.

Sprinkler irrigation on the lower end of Reach #13.

70 Reach #14

Assessment Sites: MR-86 through MR-89

Reach Description: Old Ranch Buildings to Fisher Coulee

Channel Type: Geology: The Eagle Sandstone bluffs along the valley’s edge gradually disappear and the older Telegraph Creek Formation (an interbedded shale and fine-grained sandstone), and eventually the Marias River Formation (calcareous dark-gray shale), takes its place. The valley walls become a series of rounded hills as compared to the sandstone outcrops seen upstream. Glacial till continues to cap the valley walls. The valley width averages about 1,900 feet, steadily getting wider because of the softer and more erodible valley walls. Channel sinuosity remains fairly straight at 1.2.

River Channel: The river channel pattern has changed little over the last 65 years. Subsequently, landowners have not needed to invest in bank stabilization measures other than a few concrete slabs around one of the pump site. Channel gradient is constant at about 3.1 to 3.2 feet per mile.

Most of this reach consists of a single channel with a narrow floodplain along the river’s edge. Note the rounded shale hills along the valley fringe as compared to the sandstone bluffs more common upstream.

Riparian Plant Community: Dominant Plant Community: The only overstory tree found along this reach is the plains cottonwood. The older trees are present as small groves on the high floodplain and terraces. There are an increasing number of young cottonwood seedlings along the low floodplain next to the river. Native under-story shrubs are few and scattered.

71 They include Rocky Mountain juniper, silver buffaloberry, yellow willow, common chokecherry, western white clematis, western snowberry, and sandbar willow.

Mature plains cottonwood stand typical of this reach. The under-story is mostly grass. Shrubs are few and scattered.

Young cottonwood trees growing on the low floodplain are common along this reach.

Riparian Extent: The riparian forest consists of small groves of plains cottonwood and Russian olive, typically found on the inside bends of the river. There has been little overall change since 1940 other than the spread of Russian olive. Since 1940, over 200 acres of irrigated land have been developed along the river. The majority of this development lies between Sites MR-87 and MR-88. Very little of this agricultural development necessitated removing riparian forest. Most fields have an adequate buffer separating them from the active river.

Riparian Condition: Riparian assessment scores were generally good, ranging from 70 to 75. Scores would have been higher if not for the Russian olive and Russian knapweed infestations. Livestock grazing was light or nonexistent with minimal impact on the riparian vegetation. The reduction in flood flows causes some

72 limitations on young cottonwood recruitment, although it is less pronounced than it is upstream.

Invasive Species: Russian olive trees and thickets have markedly increased in size and density. The patches of Russian olive are intermittent, but have become more frequent.

Noxious Weeds: Russian knapweed continues to be the major weed problem. Canada thistle is common as well.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Canada thistle (common) Russian olive (moderate density; single plants, thickets, and stringers)

Infrastructure: Irrigation Pumps: There are five irrigation pumps along this reach, three portable and two permanent. All, but one, are located between Sites MR-87 and MR-88. Flood and sprinkler irrigation systems have been developed on the floodplain that these pumps serve.

Portable pump site located downstream from Site MR-87. Concrete slabs are being used to protect the pump.

74 Reach #15

Assessment Sites: MR-89 through MR-94

Reach Description: Fisher Coulee to the Missouri River Confluence

Channel Type: Geology: The valley walls along this reach are exclusively Marias River Formation (calcareous dark-gray shale). They are a series of rounded hills with a layer of glacial deposit on top. The valley width averages 2,500 feet. It gradually widens as it approaches Missouri River to as much as 4,000 feet at Loma. Channel sinuosity has increased slightly to 1.3; channel gradient is 3.7 feet per mile.

River Channel: Within the last 65 years, the river channel has made significant changes: o Accelerated Bank Erosion: At Site MR-90, a 12’ high vertical bank is slowly eroding into a pump site and hay field that is irrigated with a small center pivot. Prior to the center pivot installation (about 10 years ago), there was over 200 feet of buffer separating the field from the river. The field is currently being irrigated to the river’s edge saturating the vertical bank causing it to be even more unstable. A diagonal channel bar compounds the problem by turning the current into the bank. o Channel Avulsion: A large meander at Site MR-91 was breached sometime after 1940 abandoning over one mile of river channel. o Major Channel Shift: Downstream of the Highway 87 Bridge at Loma, the river took a major shift to the south. The Marias River enters the Missouri River over 1 mile further upstream than it did in 1941. The new channel is vertically entrenched and the banks are actively eroding.

Site MR-90: River cutting into irrigated Site MR-94: Actively eroding bank between hay field. Loma and the Missouri River confluence.

75 1941 Aerial Photo: The Marias River enters the Missouri River over 1 mile further downstream than it does today.

2005 Aerial Photo: The Marias River shift to the south where it currently joins with the Missouri River.

Riparian Plant Community: Dominant Plant Community: The overstory tree found in the riparian plant community is exclusively plains cottonwood. Plains cottonwood groves consist of mature trees on the high floodplain and terraces. Under-story native shrubs are few and scattered. They include silver buffaloberry, yellow willow, and sandbar willow.

76 Riparian Extent: There is little overall change in the amount of riparian forest from what was present in 1940. However, prior to 1940, large tracts of forest appeared to have been cleared for agricultural development. There are over 200 acres of irrigated land along the river, most of it under sprinkle irrigation. There are also some non- irrigated cropland fields in the valley.

Riparian Condition: Riparian assessment scores were generally fair to good, ranging from 67 to 70. Most of the livestock grazing impacts are isolated to river bottom pastures used for summer grazing (Sites MR-89 to MR-91). The remainder of Reach #15 is typically used by livestock during non-summer months.

Invasive Species: Russian olive thickets have become more common and denser. This reach has a moderate density of Russian olive. However, there are sections of Reach #15 with high densities of Russian olive near Loma.

Noxious Weeds: Russian knapweed infestations are common. Canada thistle is present to a lesser degree.

Noxious Weed/Invasive Plant Infestations: Russian knapweed (common) Canada thistle (common) Russian olive (moderate-high density; single plants, thickets, and stringers)

Infrastructure: County Roads: Upstream from the Hwy 87 bridge, county roads encroach on the river. On the south bank, opposite Site MR-91, a gravel apron was placed on a short section of river bank to protect the road. At site MR-92, nearly ½ mile of the Colony Bay Road was carved out of the north bluff along the river. Drift off the road and bank are a source of sediment to the river.

Colony Bay Road cut into the north valley wall. Sediment off the road directly enters the river.

Loma Water Intake: The Loma County Water District surface water intake is located on the east bank of the river, approximately ¼ mile southwest of Loma, and just upstream from the Teton River confluence. It was constructed in 1980 with a water right of 75 GPM. The intake is an infiltration gallery placed in the thin veneer of gravel between the river bed and bedrock. The system services 400 residents via 120 active service connections (Loma County Water District 2002).

USGS Gaging Station: An active USGS gaging station is located 800 feet upstream from the Highway 87 bridge on the east bank. The station’s official designation is: 06102050 Marias River near Loma MT (USGS 2006). There are seasonal records (April through August) on water flow documented since June 2001. There is older flow data available for 1959 through 1972. Water quality data including biological, nutrients, inorganics, sediment, radiochemicals, and physical properties have been collected at various times since 1964.

Irrigation Pumps: There are several portable irrigation pumps along this reach that distribute Marias River water to valley bottom fields. Most systems are under sprinkle irrigation. One large permanent pumping plant is located about 1 mile upstream from the Highway 87 bridge that lifts water 150-200’ to fields (~ 1,000 acres) on the bench north of Loma.

Large pumping station (downstream from Site MR-92) that lifts water several hundred feet to fields on the upland bench north of Loma.

Portable pump located at Site MR-94 that feeds into a small center pivot on the north floodplain.

78 Planning Considerations

The following planning considerations have been developed for landowners, local government boards and districts, state/federal agencies, and the Marias River Watershed group. They are intended to assist in the prioritization of land and water improvement projects along the Marias River. The implementation of the following planning considerations would be best served using a non-regulatory approach. They are broken down as General Planning Considerations that are applicable to all or most of the 15 reaches or as Reach-Specific Considerations that would apply to a specific reach.

I. General Planning Considerations Riparian Improvements: The development of off-river livestock water, riparian pasture fencing, and the adoption of a riparian grazing management approach would help maintain or improve long-term impacts to native riparian plant density, shrub/tree regeneration, and river bank stability. These improvements are especially important where continuous summer use or concentrated winter feeding/calving areas is occurring.

Stream Bank Stabilization: Bank stabilization is often very expensive and risky. Unless there are high value properties to protect (i.e. roads, houses, barns, etc.), bank stabilization measures are usually not cost effective. In addition to the high cost, a poorly designed and/or placed bank protection structure may be difficult to maintain and can actually create a more severe stability problem. If a bank stabilization project is determined to be necessary, extensive site review and project design should be completed prior to construction to ensure that the bank stabilization measure will work as intended and will not cause off-site impacts.

Noxious Weed Control - Leafy Spurge & Spotted Knapweed: Leafy spurge and spotted knapweed will require a long-term management approach to reduce, or contain, the current levels of infestation. Infestations are the heaviest on the upper river, Reach #1 to #4. The lower end of Reach #4 should be the “battle front” against leafy spurge control. Lake Elwell currently serves as an effective buffer for the downstream migration of leafy spurge. Actively monitoring and preventing leafy spurge from flanking around the lake should be a high priority. The County Weed Districts, the Marias River Basin Weed Control Association, the Bureau of Reclamation, and private landowners should continue their cooperative approach to containing leafy spurge above Lake Elwell.

Noxious Weed Control - Russian Knapweed: An aggressive noxious weed management effort that targets Russian knapweed should be waged by the landowners and the Liberty, Hill, and Choteau County Weed Districts. Reach #8 to #15 have the heaviest infestations. The program objective would be to contain Russian knapweed infestations, as a minimum, and eradicate isolated patches where possible.

Invasive Species Control – Russian Olive: Management approaches to Russian olive control would depend upon infestation density levels. Where the Russian olive densities are low, there is an opportunity to cost-effectively eliminate Russian olive plants along the river before they become too costly to control. With a few exceptions, Russian olive

79 infestations are low from Reach #1 to #10. Downstream from Reach #10, Russian olive densities vary from low to high. Reach #10 or #11 may be where a “no spread upstream” threshold is established. The upstream reaches would fall under an eradication strategy while the downstream reaches would more realistically be a containment strategy. An information program clearly outlining the long-term benefits of an aggressive Russian olive removal effort should be developed. This information campaign would complement demonstration projects showing various removal techniques that are both cost-effective and environmentally sensitive.

Noxious Weed Prevention - Perennial Pepperweed and Salt Cedar: These noxious weeds are not commonly found within the Marias River corridor, but they are not far away and pose a serious threat. An extensive preventative campaign should be launched targeting all landowners and residents in the Marias River Basin. This campaign should enable everyone to identify these weeds and know what measures to take to effectively deal with them.

II. Reach-Specific Planning Considerations

Reach #1: Confluence of the Two Medicine River and Cut Bank Creek (Sullivan Bridge) to Willow Rounds Sullivan Bridge: Implement needed improvements to the north road approach to the Sullivan Bridge. These improvements may include: improved road surface drainage stabilization of the road embankment toe being undermined by Cut Bank Creek widen the north end of the Sullivan Bridge to accommodate a wider turn radius for large vehicles. In 2006, an engineering firm developed conceptual alternatives and cost estimates to address the road embankment problem along Cut Bank Creek. The Glacier County Road Department would be the logical lead agency.

Public Access Site at the Sullivan Bridge: Develop the BLM site to better manage vehicle access and minimize human impacts (roads, trash, and camp fires) to the riparian vegetation and channel banks.

Reach #2: Willow Rounds to the Marias Valley Golf Course Irrigation Waste Water: Pondera County Canal & Reservoir Co. has several irrigation waste ways where canal waste water is discharged directly back to the Marias River or one of its tributaries. Some of these waste ways have excessive erosion and may be a significant source of sediment to the Marias River. Further site evaluations with the canal company are needed to determine if there are irrigation water waste ways that require remediation.

Reach #3: Marias Valley Golf Course to Naismith I-15 Right of Way: There is approximately 200 feet of active bank erosion along the I-15 Right of Way. This section of river bank should be blanket rock rip-rapped, keying the new rip-rap into the rock rip-rap that already exists.

Marias Acres Subdivision Road: Due to an extensive amount of upstream bank hardening and floodplain restriction, the river is rapidly eroding into the Marias Acres Subdivision access road creating an economic and safety problem for the people who use this road. It would take an enormous amount of rock rip-rap and/or several flow deflectors to stop the erosion. This would be cost prohibitive. The cheapest (perhaps not the easiest) option would be to negotiate an alternative road right-of-way outside of the river’s channel migration zone.

Gravel Pit: Establish a buffer to separate the gravel mining operation from the edge of the valley bluff to prevent sediment drift down the bluff and into the river. All gravel pits in the region should have an aggressive noxious weed program to assure weed seeds are not being transported out of the gravel pit.

Reach #4: Naismith to Lake Elwell Dry Fork Marias River: Since the Dry Fork is a major tributary to the Marias River, a comprehensive stream assessment should be conducted to evaluate stream condition and water quality status. This assessment would complement the assessment work previously completed on the Marias River mainstem and Pondera Coulee. Active involvement of landowners would be encouraged.

Reaches # 5-8: Lake Elwell Fish Habitat: Continue the Christmas tree reef habitat enhancement project in Lake Elwell. Russian olive slash should be used in the habitat bundles.

Reach #8: Lake Elwell to the Pugsley Bridge Pugsley Bridge: A cooperative effort between the Liberty County Commissioners, the private landowner, the Marias River Watershed, BLM, and FWP is needed to address the active bank erosion immediately downstream from the Pugsley Bridge’s north abutment. An analysis of several alternatives was completed in 2006 by a private consultant. In- stream flow deflectors, both upstream and downstream from the bridge, were recommended as the most cost-effective option. A detailed survey and design will be necessary prior to construction.

Invasive Species Control - Russian Olive (Bureau of Reclamation): The General Planning Consideration that addresses Russian olive removal would apply to the majority of this reach. The exception would be the mile of river directly downstream from Tiber Dam. This section of river should be designated as a high priority since it serves as a major seed source for the lower half of the Marias River. The goal should be total eradication of Russian olive along the river. Demonstration projects that evaluate cost- effective removal techniques, native species replacement plantings, and the use of the slash (i.e. fish habitat bundles, biomass fuel, landscaping mulch, etc.) should be incorporated into this effort.

81 Reach #9: Pugsley Bridge to Circle Bridge Corrals: Encourage landowners with corrals/pens next to the river to have the local NRCS office conduct a site evaluation to determine if their corral systems are a significant source of nutrient pollution to the river. Where there are potential water quality impacts, the MRW could offer to assist interested landowners in seeking technical and financial assistance to mitigate the impacts. There may also be an opportunity to use one or more of the sites as demonstration projects.

Junk Pile Removal: Remove solid waste/junk piles off the river’s edge and transport the waste material off-site to an approved landfill.

Riparian Buffers: Effective riparian field buffers are needed along some fields to separate the active river channel from adjacent fields. Agricultural fields located between Moffat and Circle Bridges should be a targeted reach.

Meander Avulsion Upstream from Circle Bridge: Determine the landowner’s level of concern about this meander breach. If the abandonment of the channel would create an economic hardship, it may be less costly, with less environmental impact, to prevent this avulsion from happening now rather to wait until after it breaches. A detailed site survey and engineering design would be necessary prior to any remediation project being started.

Gravel Pit: Establish a buffer to separate the gravel mining operation from the edge of the valley bluff to prevent sediment drift down the bluff and into the river. The gravel pit downstream from the Moffat Bridge (south bluff) should be a high priority. All gravel pits in the region should have an aggressive noxious weed program to assure weed seeds are not being transported out of the gravel pit.

Reach #10: Circle Bridge to the Old Brinkman Gage Station Junk Pile Removal: Remove solid waste/junk piles off the river’s edge and transport the waste material off-site to an approved landfill.

Riparian Buffers: Effective riparian field buffers are needed along some fields to separate the active river channel from adjacent fields. Agricultural fields for the first six miles downstream from the Circle Bridge should be a targeted.

Reach #11: Old Brinkman Gage Station to Black Coulee Refer to General Planning Considerations

Reach #12: Black Coulee to Sheep Coulee Refer to General Planning Considerations

Reach #13: Sheep Coulee to Old Ranch Buildings Refer to General Planning Considerations

Reach #14: Old Ranch Buildings to Fisher Coulee Refer to General Planning Considerations

Reach #15: Fisher Coulee to the Missouri River Confluence Refer to General Planning Considerations

83 References Cited

Apiisoomahka Wm. Singer III, 1993. Blackfeet Confederacy Territory Map, Red Crow Community College. Cardston, Alberta. http://www.trailtribes.org/greatfalls/homeland-of-the-blackfeet.htm

Bollman, Wease. December 2005. A Biological Assessment of Sites in the Marias River Watershed: Pondera, Glacier, Toole, and Liberty Counties, Montana. Missoula, MT.

Bureau of Reclamation. Pick-Sloan Missouri Basin Program, Lower Marias Unit – Montana. http://www.usbr.gov/dataweb/html/lowmarias.html

Bureau of Reclamation and Montana Fish, Wildlife and Parks. Feb. 2007. Lower Marias River Corridor and Infrastructure Inventory.

Hamaker, Dorothy. 1967. Napi’s Lookout, the Story of Willows Rounds. Shelby Promoter Printing, Shelby, MT.

Hill County Water District. March 2001. Hill County Water District Public Water System PWSID #MT0000239. Havre, MT.

Loma County Water District. Dec. 2002. Loma County Water District PWSID# MT0002669 Public Water System. Loma, MT.

Montana Bureau of Mines and Geology. 2005. Marias River Watershed Project Phase 1 Compilation and Evaluation of Baseline Information. Butte, Montana.

Montana Department of Environmental Quality. Clean Water Act Information Center. http://www.deq.mt.us/CWAIC/default.aspx

Montana Fish, Wildlife and Parks. June 1989. Applications for Reservations of Water in the Missouri River Basin above Fork Peck Dam, Volume 3. Helena, Montana.

Rood, S.B., and Mahoney, J.M. 1995. River Damming and Riparian Cottonwoods along the Marias River, Montana. Rivers, 5: 195–207.

South Chester Water Users Association. May 2001. Source Water Delineation and Assessment Report. Chester, MT.

U.S. Geological Survey. March 2006. Water Resources Data, Montana, Year 2005, Volume 1. Report MT-05-1. 302-330.

Weber, Erich E. May 2006. Biological Integrity of the Marias River, Cut Bank Creek and the Two Medicine River, Northcentral Montana, Based on the Structure and Composition of the Benthic Algae Community. East Helena, MT.

84 Appendix A Marias River Assessment Sites

Date: 2005-2006 Page: 1

Site Latitude Longitude Bank Riparian Score Periphyton Sample Site Water Chemistry Sample Site

Number Site Description Macroinvertebrate Site Sample CC-1 Cut Bank Creek mouth 48.48670 -112.22824 X X X TM-1 Two Medicine River mouth 48.48613 -112.22833 X X X MR-1 Upstream from Sullivan Bridge; Public access site 48.48692 -112.22719 LB 85 MR-2 Riparian Site adjacent to Irrigated Hay Field 48.47913 -112.20998 RB 80 MR-3 Riparian Site - downstream from pipeline crossing 48.47652 -112.1809 RB 78 MR-4 Riparian Site 48.46775 -112.1554 LB 75 MR-5 Riparian Site 48.46167 -112.13097 LB 87 MR-6 Willow Rounds 48.44871 -112.11548 RB 68 MR-7 Napi Point: Inside bend; Reference Site 48.4415 -112.09601 LB 87 MR-8 North end of Mid-Valley Hill 48.44768 -112.08155 RB MR-9 Old Meander Cut-Off 48.45226 -112.05948 LB 70 MR-10 Riparian Site: South Valley Wall 48.44786 -112.03474 LB 75 MR-11 Abandoned Pump Site 48.45015 -112.00532 LB MR-12 Near Old Lincoln Ranch Buildings 48.44012 -111.99213 LB 63 MR-13 Braided Channel: North Side of Valley 48.44068 -111.98012 RB MR-14 Riparian Site: South Side of Valley 48.41995 -111.98085 LB 68 MR-15 Wanken Ranch 48.4175 -111.95343 RB 72 MR-16 Straight Channel next to Irrigated Field 48.42469 -111.95029 RB MR-17 Riparian Site 48.43265 -111.9285 LB 83 MR-18 Marias River Golf Course 48.4264 -111.90768 LB MR-19 Riparian Site ds from golf course; Reference site 48.4244 -111.89915 LB 82 MR-20 West side of I-15 R/W, Upstream from bridge 48.42651 -111.89322 RB MR-21 USGS Gage Station 48.42734 -111.88988 LB MR-22 Riparian Site: Across from active eroding bank 48.42187 -111.89038 LB X X X MR-23 Williamson Park 48.4244 -111.87334 LB MR-24 Straight Channel next to Irrigated Field 48.42417 -111.86338 RB MR-25 Channel Meander: South Side of Valley 48.41746 -111.86483 LB MR-26 Riparian Site: North Side of Valley 48.41983 -111.84603 RB 68 MR-27 Riparian Site: Across from irrigation pump 48.40804 -111.84685 RB 68 MR-28 Center Pivot/Irrigation Pump 48.39765 -111.84888 LB MR-29 Mid-Channel Island 48.40442 -111.82599 MR-30 Eroding Bank/Center Pivot 48.40612 -111.81971 LB MR-31 Riparian Site: Across from Railroad R/W 48.39541 -111.79139 RB 71 MR-32 Riparian Site: Upstream from Naismith 48.38834 111.78112 LB 71 MR-33 Irrigated Hay Field/ Eroding Bank 48.37192 -111.77127 LB MR-34 Old Fort Conrad/BNSF Railroad Bridge 48.37283 -111.75988 MR-35 Sheep Pasture/Meander Cut-Off 48.37734 -111.73892 LB MR-36 Upstream from F Bridge 48.37991 -111.71641 RB X X X MR-37 Riparian Site 48.38808 -111.71244 LB 80 MR-38 Riparian Site (BOR): Reference Site 48.39411 -111.69072 LB 85 MR-39 Riparian Site; Old channel meander 48.39183 -111.66062 LB 80 MR-40 Lake Elwell Backwater 48.3712 -111.64714 RB MR-41 Below Tiber Dam 48.31693 -111.09208 MR-42 Across from Sanford Park 48.31224 -111.09303 RB 75 MR-43 Riparian (RB); USGS Gaging Station (LB) 48.30652 -111.08077 RB 85 MR-44 Riparian Site 48.29456 -111.07637 LB 77 MR-45 Riparian Site 48.28862 -111.06657 LB 71 MR-46 Riparian Site 48.29206 -111.05534 RB 71 MR-47 Pugsley Bridge 48.29091 -111.04654 MR-48 Riparian Site 48.2826 -111.04719 LB 85 MR-49 Pondera Coulee mouth; Reference Site 48.27277 -111.04382 RB 87 MR-50 Riparian Site 48.26152 -111.02325 LB 68 MR-51 Riparian Site: North Valley Wall 48.27153 -111.00368 RB 71 MR-52 Moffat Bridge 48.26473 -110.99091 MR-53 Riparian Site: South Side of Valley 48.26588 -110.98002 LB 67

85 Appendix A Marias River Assessment Sites

Date: 2005-2006 Page: 2

Site Latitude Longitude Bank Riparian Score Periphyton Sample Site Water Chemistry Sample Site

Number Site Description Macroinvertebrate Site Sample MR-54 Riparian Site: North Valley 48.2695 -110.95293 RB 65 MR-55 Field along River's Edge 48.26821 -110.92007 LB MR-56 Riparian Site:Inside Bend, North Valley Bluff 48.26957 -110.91197 RB 62 MR-57 Riparian Site 48.25944 -110.90002 RB 70 MR-58 Upstream from Circle Bridge: Sample Site 48.25832 -110.89501 XXX MR-59 Circle Bridge 48.25945 -110.89118 MR-60 Irrigation Pump Site 48.25486 -110.881 RB MR-61 Riparian Site: Inside Bend 48.25748 -110.87741 LB 73 MR-62 Riparian Site: Inside Bend 48.25978 -110.85207 LB 77 MR-63 Old Irrigation Pump Site 48.2687 -110.86449 LB MR-64 Irrigation Pump Site 48.26989 -110.84417 LB MR-65 Irrigation Pump House 48.26433 -110.84185 LB MR-66 Riparian Site 48.26079 -110.82436 RB 78 MR-67 Riparian Site: Beginning of Sandstone Bluffs 48.2475 -110.83854 RB 80 MR-68 Irrigation Pump House 48.22927 -110.78269 RB MR-69 Riparian Site 48.23563 -110.7588 LB 70 MR-70 Irrigation Pump Site 48.25312 -110.74432 LB MR-71 Brinkman Gage Station - Inactive 48.26347 -110.713 LB MR-72 Inverness Pump Plant 48.26318 -110.70756 LB MR-73 Riparian Site: Braided Section 48.24401 -110.6728 LB 62 MR-74 Riparian Site 48.24616 -110.63661 RB 78 MR-75 Bitner Grove 48.23735 -110.62045 LB MR-76 Irrigation Pump Site 48.23253 -110.61917 LB MR-77 Riparian Site 48.20087 -110.61782 LB 70 MR-78 Irrigation Pump Site - Portable Pump 48.19116 -110.61104 LB MR-79 Irrigation Pump: Sample Site 48.18148 -110.61715 LB X MR-80 Riparian Site 48.17147 -110.62204 RB 70 MR-81 Large Irrigation Pump 48.161 -110.63466 RB MR-82 Riparian Site 48.12987 -110.66246 RB 80 MR-83 Well/Sump 48.11608 -110.67413 LB MR-84 Riparian Site 48.09073 -110.6798 LB 82 MR-85 Riparian Site 48.05106 -110.67884 RB 73 MR-86 Ranch Buildings: Abandoned 48.04014 -110.67746 RB X MR-87 Riparian Site 48.00538 -110.65358 LB 75 MR-88 Irrigation Pump Site 47.99643 -110.62683 RB MR-89 Riparian Site 47.96996 -110.5968 LB 70 MR-90 Irrigation Pump Site/ Eroding Bank 47.94979 -110.58896 LB MR-91 Riparian Site 47.94141 -110.55843 LB 67 MR-92 Colony Bay County Road 47.94671 -110.5269 LB MR-93 Loma Bridge 47.93164 -110.50706 MR-94 Irrigation Pump/Upstream from Mouth 47.92974 -110.49535 LB XXX TR-1 Teton River: Upstream from Mouth 47.93239 -110.51434 X