Home <<< Ground
Water Investigation Program <<< GWIP Projects |
The Project Numbers are assigned for identification and do not indicate priority, importance, or ranking.
The red outlines on the inset maps follow watershed boundaries. The actual study site boundaries will typically be a smaller area within these borders.
Project Number 1 Project Name: Eureka
Primary MBMG-GWIP Staff: Unassigned
County: Lincoln
Approximate Area (square miles): 60
Drainage Name(s): Tobacco River
Problem Statement: As with many other areas of the state, land use
in the area near Eureka is shifting from agricultural to individual houses
and subdivisions. DEQ received 1,670 applications for 5,556 lots from 1991 through 2008. The cumulative
effects on groundwater quality from individual septic systems in the area of
Eureka are of concern.
Project Elements: The shift from crop irrigation wells and ditches to individual
domestic wells with increasing housing density will be evaluated through groundwater
and surface-water modeling. Water-level/discharge and water-quality data from
wells and streams will be used to construct detailed potentiometric maps and
a water balance for the area. Deeper wells may be needed to define the
extent of suspected confined aquifers. A detailed groundwater flow model
will include the pumping/injection systems and evaluate the impact of growth
on water availability and quality.
Project Number 2
Project Name: Flathead Valley: Deep Aquifer — Fact Sheet
Primary MBMG-GWIP Staff: John Wheaton (406.496.4848); James Rose (406.496.4829.)
County: Flathead
Approximate Area (square miles): 150
Drainage Name(s): Flathead, Whitefish, Stillwater
Problem Statement: Population in the basin has increased by more than 25 percent in the last decade and is currently about 70,000, all of whom, with the exception of Whitefish, rely on groundwater for municipal, domestic, industrial, and irrigation supply. Continued growth and declining water levels in the main aquifer (deep confined aquifer) have raised concerns about the long-term sustainability of the water supply.
Project Elements: Installation of nested wells will be used to characterize the hydrologic relationship between the shallow aquifers and the deep confined aquifer. Aquifer tests and water chemistry analyses in shallow and deep aquifers will define aquifer properties. Aquifer vulnerability will be evaluated through water chemistry and groundwater age dating. The new project data along with groundwater/surface-water elevation data from recent studies throughout the area will be used to construct a groundwater flow model.
Project Number 3
Project Name: Smith Valley
Primary MBMG-GWIP Staff: Unassigned
County: Flathead
Approximate Area (square miles): 30
Drainage Name(s): Ashley Creek
Problem Statement: Low well yields and increased development in the Smith Valley and concern about dewatering of Ashley Creek resulted in a petition for a controlled groundwater area in 2005. Groundwater is obtained from fractured bedrock and alluvial basin fill. The sources of groundwater recharge, the relationship between the fractured bedrock and alluvial aquifers, and the stream-aquifer interaction are poorly known.
Project Elements: Installation and testing of wells in transects across the valley, in the fractured bedrock and alluvium, will be used to characterize the hydrologic relationship between the aquifers and Ashley Creek. A groundwater flow model will be used to define each aquifer as well as provide information as to the effects and limits of future development, particularly with respect to the fractured bedrock aquifer.
Project Number 4
Project Name: Noxon, Clark Fork River
Primary MBMG-GWIP Staff: Unassigned
County: Sanders
Approximate Area (square miles): 72
Drainage Name(s): Clark Fork River near Noxon
Problem Statement: Home sales and home sale prices have increased steadily over the past few years. Similarly, subdivision applications have increased from about 28 in 1990 to a recent maximum of 73 in 2006. There were 882 applications for subdivisions for a total of 3,014 lots from 1991 to 2007 in Sanders County.
Project Elements: Most wells in the area are shallow; as development continues, deeper wells may become necessary. Drilling and coring at several sites will be done to define the lithology and the bedrock/alluvium contact at depth and at the valley margins. Aquifer tests and water chemistry analyses at shallow and intermediate depths at these sites will define aquifer properties and will be used to evaluate aquifer vulnerability. New groundwater/surface-water elevation data will be used to construct a groundwater flow model.
Project Number 5
Project Name: Missoula Valley
Primary MBMG-GWIP Staff: Unassigned
County: Missoula
Approximate Area (square miles): 40
Drainage Name(s): Clark Fork River
Problem Statement: The city of Missoula is unique in Montana with its large development of groundwater for the municipal water supply. However, removal of the Milltown dam, expansion of sand/gravel pits, and a rapidly expanding population are changing groundwater flow quality and quantity in the Missoula Valley. The valley-fill aquifer is comprised of coarse gravel and cobbles which makes for a very productive aquifer, but the shallow water table also provides rapid movement of contaminants. The deeper portions of the aquifer remain unexplored.
Project Elements: Development of the deeper portions of the aquifer necessitates drilling and testing of deep wells. Lithology and aquifer parameters from the test wells will be compiled with existing and new water-level data to develop a groundwater flow model of the Missoula basin above its confluence with the Bitterroot River. Water quality, including pharmaceuticals and personal care products, will be assessed with regard to their potential for migration to deeper portions of the valley-fill aquifer.
Project Number 6
Project Name: Florence Area — Fact Sheet
Primary MBMG-GWIP Staff: John Wheaton (406.496.4848);;; Ginette Abdo (406.496.4152); Dean Snyder( 406.496.4882).
County: Ravalli
Approximate Area (square miles): 30
Drainage Name(s): Bitterroot, One Horse Creek, Eightmile Creek
Problem Statement: High-density well and septic development in and around Florence and the Eightmile Creek Drainage have raised concerns about groundwater availability and groundwater contamination.
Project Elements: Lithologic data from drilling and coring at several sites throughout the area will be used to characterize the hydrogeologic framework. Aquifer tests and water chemistry analyses at shallow and intermediate depths at several sites will define aquifer properties and evaluate aquifer vulnerability. The groundwater flow model will focus on the potential depletion effects on small streams as well as the changing groundwater flow paths induced by new development.
Project Number 7
Project Name: Hamilton Area
Primary MBMG-GWIP Staff: Unassigned
County: Ravalli
Approximate Area (square miles): 30
Drainage Name(s): Bitterroot, One Horse Creek, Eightmile Creek
Problem Statement: Conversion of irrigated land to residential development has raised concerns about groundwater availability and groundwater contamination.
Project Elements: Drilling and coring at several sites throughout the area will define the hydrogeologic framework. Detailed canal seepage measurements will be used to characterize irrigation (incidental) recharge. Aquifer tests and water chemistry analyses at shallow and intermediate depths in the floodplain and on the upland benches will define aquifer properties and evaluate aquifer vulnerability. New project data along with groundwater/surface-water elevation data from recent studies throughout the area will be used to construct a groundwater flow model.
Project Number 8
Project Name: Georgetown Lake - Phillipsburg
Primary MBMG-GWIP Staff: Unassigned
County: Granite and Deerlodge
Approximate Area (square miles): 35
Drainage Name(s): Flint Creek
Problem Statement: Rapid subdivision of private land around the lake has raised some concerns with nitrate loading on the lake. In addition, pressure for development in the Phillipsburg area has increased the need to evaluate the transition from flood and center pivot agricultural land use to local subdivisions. Senior water users in this basin have some of the oldest water rights in the state. The shallow groundwater system has been evaluated in past investigations of irrigation return flow. The deeper aquifer(s), however, is likely to be targeted for development as the demand for water outside the influence of septic systems grows.
Project Elements: Compilation of existing surface-water and groundwater data will be used to construct a conceptual model of the shallow system and serve to guide evaluation of the deeper aquifers of the Flint Creek Valley. A groundwater flow model will be used to evaluate the basin-specific transition from flood/pivot irrigation to domestic use.
Project Number 9
Project Name: Summit Valley (Butte)
Primary MBMG-GWIP Staff: Unassigned
County: Silver Bow
Approximate Area (square miles): 40
Drainage Name(s): Silver Bow Creek, Blacktail Creek
Problem Statement: Groundwater in well and septic systems in high-density residential developments has been contaminated by nitrate. The elevated groundwater nitrate has also impacted Silver Bow and Blacktail Creeks. Concern about groundwater and surface-water contamination from septics has restricted development in the Summit Valley. The deep valley aquifer south of Butte provides good opportunity for groundwater development for new subdivisions. Near-surface alluvial material derived from the granitic bedrock, however, does not favor septic systems. Elevated concentrations of nitrates have prompted Butte–Silver Bow and DEQ to increase lot sizes in new subdivisions. Evaluation of deeper groundwater with respect to quality and quantity has not been done. Development on the valley margins relies on the fractured-bedrock aquifer that has proven to be quite variable with respect to production and vulnerability to septic contamination. Although a few wells penetrate the deeper aquifer, its yield and water quality are largely undocumented.
Project Elements: Water-quality data related to nitrates and pharmaceuticals will be collected throughout the basin along with chemistry and physical properties of the local soils to estimate the fate and transport of septic effluent. Test wells will be installed in the intermediate and deep aquifer(s) of the valley-fill material to estimate yield and aquifer vulnerability. A groundwater flow model will be used to evaluate groundwater development and the potential for mixing waters from shallow and deep aquifers.
Project Number 10
Project Name: Priest Butte Lake - Teton River
Primary MBMG-GWIP Staff: Unassigned
County: Teton
Approximate Area (square miles):
Drainage Name(s):
Problem Statement: The Teton River Water Quality Restoration Plans called for a groundwater assessment of the Priest Butte Lake area to assist in refinement of salinity load allocations. Priest Butte Lake has been previously studied, but the characteristics of the shallow groundwater that drains into the lake have not. An extensive groundwater study was completed around Freezeout Lake, Benton Lake, and surrounding areas.
Project Elements: A groundwater monitoring plan needs to be implemented to better understand the geology and groundwater of the area and the load on Priest Butte Lake. Groundwater studies will take place in irrigated areas between Choteau and Bynum and along the Teton River to determine losing/gaining reaches of a stream. Identification of land practices that contribute to increased salts and salinity will be used to supplement or support groundwater data.(Information for this project taken from the Executive Summary of the TetonMasterDoc8_18_03)
Project Number 11
Project Name: Greenfields Bench area
Primary MBMG-GWIP Staff: Unassigned
County: Teton
Approximate Area (square miles): 100
Drainage Name(s): Sun River / Muddy Creek
Problem Statement: Groundwater in the Greenfields Bench area depends largely on recharge from irrigation canals diverted from the Sun River via Gibson Dam and Pishkun Reservoir. Leakage from these canals into the 3- to 50-foot-thick terrace gravel deposits of the bench provide recharge to domestic wells. Recent applications for subdivisions in this area indicate a growing interest to redevelop irrigated acreage for domestic use. A relatively thin aquifer will be particularly susceptible to changes in land use, with respect to both quantity and quality.
Project Elements: Previous investigations by the MBMG, Montana Department of Agriculture, and others have described the hydrogeology of the area as well as estimated water balances for the bench area. Monitoring of water quality is in process. This investigation will include construction of a groundwater flow model based on data compiled from previous work as well as new data. The model will be used to evaluate the potential changes in groundwater flow and quality under various land-use changes.
Project Number 12
Project Name: North Hills (Helena)
Fact Sheet: March 2011 and Aug 2011
Primary MBMG-GWIP Staff: Kirk Waren (406.496.4866);
Julie Ahern Butler(406.496.4854); Andy Bobst( 406.496.4409)
County: Lewis and Clark
Approximate Area (square miles): 60
Drainage Name(s): Silver Creek
Problem Statement: The North Hills study area is an unincorporated area where both subdivisions and individuals rely on groundwater. Septic systems are a common wastewater treatment approach. Increasing development and declining groundwater levels resulted in the establishment by the Montana DNRC of a temporary Controlled Groundwater Area (CGWA) in 2002. After a study was completed through a cooperative effort by the MBMG, the Lewis and Clark County Water Quality Protection District, and the DNRC, the temporary CGWA was terminated in 2006. The matter was reevaluated in 2008, resulting in the establishment of a second, smaller CGWA. The primary concerns are the likelihood of impacts from continued groundwater development and the practice of using individual septic systems in dense housing developments.
Project Elements: This investigation will provide more accurate descriptions of the geologic setting, hydrologic properties of the aquifers available, water supplies, and stresses on the hydrologic systems. Work will include assembling existing data and reports, establishing new meteorological and hydrologic monitoring, drilling exploratory and test wells, conducting aquifer tests, water-quality sampling, and evaluating transpiration consumption by both crops and natural vegetation. A numerical groundwater model will be constructed to simulate observed hydrogeologic conditions and evaluate the response of the groundwater system to specific stresses such as new wells or well fields.
Project reports: January 2010 Update (pdf file7.9 Mb)
May 2010, Helena Area update (pdf file 2.85 Mb)
May 10, 2010, Helena Area Progress Report (pdf file 0.06 Mb)
June 2010, Helena Area Update (pdf file 34.4Mb)
July 1, 2010, Helena Area Progress Report (pdf file 0.06 Mb)
September, 2010, Helena Area Progress Report (pdf file 0.03 Mb)
December, 2010, Helena Area Progress Report (pdf file 0.04 Mb)
July, 2011, Helena Area Progress Report (pdf file 0.035 Mb)
Dec, 2011, North Hillis Area Update — Hydrogeology (pdf file 4.53 Mb)
— Water Modeling (pdf file 3.76 Mb)
 |
 |
 |
 |
 |
 |
Project Number 13 Project Name: Scratch
Gravel Hills (Helena)
Fact Sheet: March 2011 and Aug 2011
Primary MBMG-GWIP Staff: Kirk
Waren (406.496.4866
); Andrew Bobst (406.496.4409)
County: Lewis and Clark
Approximate Area (square miles): 70
Drainage Name(s):
Problem Statement: Similar to the North Hills area,
subdivisions and declining water levels have been observed, but lack
of data prevents any evaluation of cause and effect. The geology of
the Scratch Gravel Hills area is much different than that of other areas in
the Helena Valley. Alluvial fans have been deposited on faulted
granitic bedrock.
Project Elements: Drilling and coring
at several sites throughout the area will establish lithology, particularly
with respect to depth to bedrock. Aquifer tests and water chemistry analyses
in the alluvial fan and the underlying bedrock of these sites will define
aquifer properties and will be used to evaluate aquifer vulnerability. New
project data along with groundwater/surface-water elevation data
from recent studies throughout the area will be used to construct
a groundwater flow model.
Project reports: May
2010, Helena Area update (pdf file 2.85 Mb)
May
10, 2010, Helena
Area Progress Report (pdf file 0.06 Mb)
June
2010, Helena
Area update (pdf file 34.4Mb)
July
1, 2010, Helena
Area Progress Report (pdf file 0.06 Mb)
September, 2010, Helena Area Progress Report (pdf file 0.03 Mb)
December, 2010, Helena Area Progress Report (pdf file 0.04 Mb)
July, 2011, Helena Area Progress Report (pdf file 0.035 Mb)
December, 2011 ScratchgravelHills Update (pdf file (4.87 Mb)
Project Number 14 Project Name: Townsend–Toston
area
Primary MBMG-GWIP Staff: Unassigned
County: Lewis and Clark, Broadwater
Approximate Area (square miles):
Drainage Name(s):
Problem Statement: The Townsend–Toston area is along
the Missouri River just above Canyon Ferry Lake. Although some
subdivisions have been developed in several areas, the main concern
is the conversion from flood to center pivot irrigation. Similar
to other areas in the state, the Toston irrigation canal and other
such canals represent considerable recharge to the near stream aquifers.
There are several applications for irrigation well permits: flood irrigation
from canals fed by the Toston and other canals and ditches.
Project Elements: This area will
benefit from a groundwater modeling effort to evaluate the many potential
changes in land use, particularly the change from flood to pivot irrigation. Test
wells will be installed throughout the area to evaluate aquifer properties
and extent. The model will be constructed based on existing
irrigation canals and wells with an emphasis on stream depletion/accretion.
Project Number 15 Project Name: North of Three Forks (vicinity of the
intersection of Hwy 287 with I-90)
County: Broadwater
Primary MBMG-GWIP Staff: Unassigned
Approximate Area (square miles): 50
Drainage Name(s): Upper Missouri
Problem Statement: Dryland, flood, and
center pivot irrigation is being replaced by development of subdivisions
throughout the area. Agriculture relied on deeper (200+ feet) wells for
much of its water in the past few years. Domestic/exempt wells
will likely become a popular means of water supply for the thousands
of new lots along the Hwy 287 / I-90 corridor. Most of the groundwater
development in this area will rely on semi-consolidated Tertiary-age
sediments on the flanks of the upper Missouri River valley.
Project Elements: Reported well yields
for this area range from less than 1 gallon per minute to over 1,000
gallons per minute; this range indicates the large variability in aquifer
properties over a small area. Development of groundwater and its effect
on stream flow will be similarly variable. Test wells will be
installed at various locations based on existing wells; aquifer tests
will be used to document aquifer properties for the area. A groundwater flow model will be constructed to evaluate change from a few
irrigation wells to many domestic wells; emphasis will be on future
development of domestic groundwater and evaluation of a few public
water supplies versus many individual wells.
Project Number 16 Project Name: Gallatin
Valley Manhattan
Primary MBMG-GWIP Staff: Unassigned
County: Gallatin
Approximate Area (square miles): 6
Drainage Name(s): Gallatin River at Logan
Problem Statement: The Manhattan–Logan
area is the spill point for the Gallatin River exiting the valley. Subdivisions
have been developed in several areas west and north of Manhattan as
well as the Church Hill area south of Manhattan. The deeper Tertiary-age
aquifers at depth have proven to be very productive for agricultural
use. There are several applications for irrigation well permits; flood
irrigation from canals fed by the West Gallatin River and its tributaries
is being converted to center pivot fed by groundwater in several areas.
Project Elements: This area warrants
an intense groundwater modeling effort to evaluate the many potential
changes in land use. Test
wells will be installed throughout the area to evaluate aquifer properties
and extent. The model will be constructed based on existing
irrigation canals and wells with an emphasis on stream depletion/accretion.
Project Name: Belgrade–Lower
West Gallatin River — Fact
Sheet
County: Gallatin
Primary MBMG-GWIP Staff: Tom
Michalek (406.496.4405); Mary
Sutherland (406.496.4410)
Approximate Area (square miles): 5
Drainage Name(s):
Problem Statement: Recent subdivisions utilizing
septic systems and community wastewater treatment are replacing agricultural
land use, particularly dairy operations as well as irrigated and non-irrigated
pasture. The Gallatin County Water Quality District collected
water-quality data: preliminary results suggest elevated nitrate
concentrations result more from recent development than past agricultural use. Their
water-level data also indicate a disparity between groundwater flow
directions mapped in the 1960s versus those mapped in the 1990s. All
of the wells in the area are completed at shallow depths—usually
less than 100 feet—in an area where the Gallatin River is a losing
stream. This area is 
particularly important with respect
to groundwater/surface-water interaction.
Project Elements: Monitoring and test wells
will be installed at key locations throughout the area to investigate
groundwater flow gradients (both vertical and horizontal) and the
evolution of water chemistry. A detailed elevation surface of
new and existing wells will be conducted to augment work done by the water-quality district. The objective of this project will be to construct
a groundwater flow model of the lower West Gallatin River at and above
its confluence with the East Gallatin River and Hyalite Creek.
Well drilling for extensive aquifer testing has begun in the Gallatin Valley study areas of Four Corners and Belgrade-Lower West Gallatin. A total of four sites are planned.
Project Number 18 Project Name: Four Corners–Bozeman
— Fact Sheet
Primary MBMG-GWIP Staff: Tom
Michalek (406.496.4405) Mary
Sutherland (406.496.4410)
County: Gallatin
Approximate Area (square miles): 5
Drainage Name(s): West Gallatin River
Problem Statement: Subdivision of
agricultural land has partially evolved from individual septic to
commercial public water supply coupled with public wastewater treatment
utilizing both surface and groundwater. Planned or proposed
expansion of the coupled system along with planned aquifer storage
recovery offers alternatives to conventional water supply and treatment
options. The impact of these systems has been the subject of
question, particularly by non-participants and senior water rights
holders. As with other small sub-basins in the Gallatin Valley,
the density of development with respect to groundwater and surface
water warrants a detailed groundwater flow model.
Project Elements: Water-level and
water-quality data collected and made available by private operators
as well as researchers will be compiled and used to construct detailed
potentiometric maps and a water balance for the area. Deeper
wells may be needed to define the extent of suspected confined aquifers. A
detailed groundwater flow model will include the pumping/injection
systems and evaluate potential managed groundwater storage on the
valley margins.
Project Number 19 Project Name: Pine Creek
Primary MBMG-GWIP Staff: Unassigned
County: Park
Approximate Area (square miles): 40
Drainage Name(s): Pine Creek
Problem Statement: Paradise Valley is
historically a very productive agricultural landscape. The natural beauty
of the Yellowstone River and the Absaroka and Gallatin Mountain ranges
has made this valley a popular location for non-agricultural development. The
small stream valleys on either side of Paradise Valley have been the
focus of much of this development. Wells in these valleys are
completed in bedrock aquifers. Bedrock aquifers may form the
majority of the stream flows during low-flow periods. The interaction
of these small drainages and the bedrock aquifers with the large alluvial
aquifer of the Yellowstone River valley is not well understood. Increasing
use of bedrock aquifers may impact baseflow on small streams, thereby
impacting groundwater users in the lower part of Paradise Valley.
Project Elements: A ten-mile stretch
of the Yellowstone River alluvial valley, centered upon the small town
of Pine Creek and extending up into the Pine Creek Valley on the east
side of Paradise Valley, has been identified for modeling. Using
existing data and data from monitoring wells installed as part of this
project, a model will be developed which will: (1) identify the interaction
of bedrock aquifers and Pine Creek, (2) identify the interaction of Pine Creek
and the alluvial Yellowstone River valley, and (3) predict the impact
future development may have upon downgradient users and minimum flows
in Pine Creek.
Project Number 20 Project Name: West Yellowstone, north side of Hebgen
Lake
County: Madison
Primary MBMG-GWIP Staff: Unassigned
Approximate Area (square miles): 25
Drainage Name(s): Madison River, Grayling Creek
Problem Statement: West Yellowstone
has undergone several growth cycles which prompted changes from individual
to public water supply in the early 1990s. Development of subdivisions
north beyond the public system renews concerns about nitrate loading
and groundwater development on Grayling Creek and the Madison River. The
latter exhibits elevated concentrations of arsenic as a result of geothermal
discharge from Yellowstone Park. The lower Madison River drainage
has experienced problems with arsenic in groundwater as a result of
flooding, both natural and irrigation. Development of groundwater in the Madison River floodplain could cause similar problems
for new subdivisions as well as the existing PWS. The MBMG conducted
a well inventory and collected some baseline samples just prior to
the shift from individual wells to the PWS in the early 1990s. Other
than data collected for the Yellowstone Controlled Ground Water Area
monitoring program, few samples have been collected to evaluate the
effects of expanded development on surface-water and groundwater quality
and quantity.
Project Elements: In addition to an
updated well inventory, water chemistry samples will be collected with
an emphasis on wells not sampled in the original work. A groundwater
flow model will address the impact of development on the smaller tributaries
as well as the Madison River; the potential for arsenic contamination
by pumping near the Madison will also be addressed .
Project Number 21 Project Name: Monarch/Belt
Primary MBMG-GWIP Staff: Unassigned
County: Cascade
Approximate Area (square miles): 120
Drainage Name(s): Belt Creek
Problem Statement: Subdivisions are
using the Madison limestone aquifer. In the area of Monarch and Belt, most wells
are in the Kootenai formation; however, as development increases and
water in this shallow aquifer reaches its limit, the deep Madison Limestone
will be the likely target. In this and several areas, the Madison
Limestone presents a potential target for aquifer storage recovery
(ASR).
Project Elements: Several wells have
been completed in the Madison aquifer, but test data are limited. Existing
wells and new observation wells will be tested to provide basic
information for the preliminary groundwater flow model. The
model results will guide additional field studies that may include
installation of production/test/observation wells and geochemical studies. The
modeling will evaluate the current and potential impact of development
on water levels in the Madison aquifer. Additionally, modeling
will be used to explore the merits of aquifer storage recovery.
Project Number 22 Project Name: Madison
aquifer between Little Belt and Big Snowy Mountains
Primary MBMG-GWIP Staff: Unassigned
County: Lower Judith Basin and Fergus
Approximate Area (square miles): >100
Drainage Name(s): Multiple
Problem Statement: The Madison aquifer is one
of the most important and widespread aquifer systems in Montana. Recharge
occurs at limited areas of outcrop around uplifted areas such as the
north side of the Little Belt and Big Snowy Mountains. With increasing
distance from recharge, the depth to the Madison typically increases
and water quality decreases. Water usability is assumed to be
limited to areas near recharge. Little is known about
the aquifer characteristics between the Little Belt and Big Snowy uplift. This
giant aquifer system is assuredly being under utilized in some areas
but increasing demand will threaten existing uses in others.
Project Elements: A digital model will
be generated for the project area to help evaluate aquifer recharge,
storage, production capacity, and sensitivity to impacts. Dedicated monitoring wells
will be installed at several sites. Aquifer tests, water chemistry,
and isotope analyses will be used to evaluate the aquifer system. The
study may also include a comprehensive survey of spring discharges
using geochemistry to identify the Madison as a source. A general,
regional model will be constructed to help understand the timing of
impacts from pumping to address concerns related to the continuing
interest of using the Madison for municipal as well as industrial (coal
plants) uses. Existing data will be evaluated to determine reliability,
and in combination with new data collected will be used to calibrate
the model. Additional areas of Madison recharge and utilizations will
be identified for future modeling and evaluation projects.
Project Number 23 Project Name: Stillwater
Valley bedrock aquifers
Primary MBMG-GWIP Staff: Unassigned
County: Stillwater
Approximate Area (square miles): 221
Drainage Name(s): Rosebud Creek, Stillwater River
Problem Statement: Land in this area that has
traditionally been agricultural range or hay land is increasingly being
subdivided. The density of wells is increasing and will continue
to increase, as each lot requires a water supply. Rightfully
or not, this pits older and newer water rights against each other,
typically with little data to support either side. Questions
about the source of recharge to the bedrock aquifers prompted the formation
of the Horse Creek Temporary Controlled Ground Water Area. The
interaction between the groundwater and surface-water systems is also
a sensitive issue that needs to be resolved.
Project Elements: Detailed aquifer parameters
will be collected by drilling and completing dedicated monitoring wells
in specific geologic units. Aquifer pumping tests, water chemistry,
and isotope analyses will be used to identify recharge and flow direction
and to evaluate aquifer sensitivity and water quality. The new and existing data will be used to create a bedrock
groundwater flow model with an interface with the rivers. Currently,
an alluvial groundwater/surface-water model is being constructed on
the middle reach of the Stillwater River. These two models will
lend understanding to the sensitivity of the bedrock and alluvial aquifers
in the region.
Project Number 24 Project Name: Rock Creek (Red Lodge to Joliet)
Primary MBMG-GWIP Staff: Unassigned
County: Carbon
Approximate Area (square miles): 100
Drainage Name(s): Rock Creek/Clark’s
Fork of the Yellowstone
Problem Statement: Shallow aquifers
underlie alluvial terraces along Rock Creek from the mountains to the
confluence with the Clark Fork of the Yellowstone River. Recharge appears
to be dominated by artificial recharge associated with flood irrigation.
The land along Rock Creek is being rapidly subdivided and developed,
changing the predominant land use from flood-irrigated agriculture
to suburban and vacation housing. There is a significant need to understand and manage
these aquifer resources to protect existing supplies and surface-water
resources while developing additional water for domestic supplies,
communities, agriculture, and industry. Since this aquifer is
artificially recharged, changing land uses and methods of water distribution
may significantly impact the aquifer and existing water resources. The
primary goal of this project is to determine potential changes to water
resources caused by the change in land use.
Project Elements: Drilling and well construction
are needed to better define the geometry of the aquifer system. Aquifer
tests, response tests, water-use monitoring, water-level monitoring,
and water chemistry analyses are needed to define the hydrogeology
and better define aquifer properties and will be used to evaluate
aquifer vulnerability. New project data along with groundwater/surface-water elevation data from recent studies throughout the area
will be used to construct a groundwater flow model.
Project Name: Pryor Mountains/Clark’s
Fork
Primary MBMG-GWIP Staff: Unassigned
County: Carbon
Approximate Area (square miles): 50
Drainage Name(s): Rock Creek and Clark’s
Fork of the Yellowstone
Problem Statement: Population growth and
interest in deep aquifers has prompted increased drilling in the Silesia-Rockvale-Edgar
area. Madison aquifer recharge originates along the northwest
flank of the Pryor Mountains. Known discharge from the Madison
is to springs such as the Blue Water Fish Hatchery and wells, but most
flows out of the area and is not utilized. Overlying aquifers
are recharged further north toward Five Mile and Cottonwood creeks. However,
overlying aquifers such as the Frontier Sandstone near the top of the
Belle Fourche are surprisingly productive in some areas. The
Frontier subcrops in the Clark’s Fork alluvium while the Kootenai
and Madison dip under the valley fill. Flowing wells in the Rockvale
area indicate that upward flow through fractures from the Kootenai
or Madison may be a source of recharge to the shallower aquifers.
Project Elements: Three deep monitoring wells will be drilled. Extensive water
quality, isotope analyses, and geochemical modeling (i.e., Minteq) will
be used to identify the source of water in these aquifers and interconnections
between the bedrock aquifers. Samples will be collected from
wells and springs. Aquifer tests, water-level data, and chemical
and isotope data will be used to generate a conceptual model. A
digital model will be built upon the conceptual model and calibrated
against the collected data. Though south of this project area,
results from several past studies of the Blue Water Creek area will
be included in development of the conceptual model.
Project Number 26 Project Name: Park City
Primary MBMG-GWIP Staff: Unassigned
County: Stillwater
Approximate Area (square miles): 40
Drainage Name(s): Yellowstone River Valley
Problem Statement: Population
in Stillwater County has grown by 32% since 1990 (2007 census data).
Expanding development west of Laurel to Park City is mainly taking the
form of 1 to 5 acre “ranchettes” that replace irrigated farmland.
Flood irrigation of the valley has been shown to create shallow aquifers
that are then used as a source of domestic water. Reducing or
removing the source of recharge by converting flood-irrigated land
to subdivisions will lower the water table, potentially impacting existing
water users. Some areas may be extremely sensitive to loss of
irrigation recharge. Identification
of the sensitivity of areas of the shallow aquifers will allow scientifically
based decision making to guide county planning along the Yellowstone
River.
Project Elements: Aquifer characterization
that has been well-documented from Billings to Laurel will be extended
to Park City to account for the large number of new houses using exempt
wells in this area. Monitoring of private wells, in addition to dedicated
monitoring wells installed and instrumented with data loggers as part
of this project, will be used to characterize seasonal groundwater
trends. These trends, in conjunction with irrigation ditches,
springs, and stream flows will be used to calibrate a model that can
be used to predict future trends under increasing aquifer use and decreasing
irrigation.
Project Number 27 Project Name: West Billings
Primary MBMG-GWIP Staff: Unassigned
County: Yellowstone
Approximate Area (square miles): 60
Drainage Name(s): Yellowstone
River
Problem Statement: Shallow aquifers
underlie alluvial terraces in the Yellowstone Valley near Billings. Recharge appears
to be dominated by artificial recharge associated with flood irrigation.
The West Billings area is being rapidly subdivided and developed, changing
the predominant land use from flood-irrigated agriculture to suburban
housing. There is a significant need to understand and manage
these aquifer resources to protect existing supplies and surface-water
resources while developing additional water for communities, agriculture,
and industry. Since this aquifer is artificially recharged, changing
land uses and methods of water distribution may significantly impact
the aquifer and existing water resources. One goal will be to
define important recharge areas and mitigate land use and operational
changes in these areas to maximize recharge. A particular interest
for the city of Billings is to develop artificial recharge basins using
storm-water runoff to maintain these aquifers, thereby reducing demand
on the municipal water supply and more importantly reduce treatment
requirements of storm water that appear to be on the regulatory horizon
because of TMDL.
Project Elements: Drilling and well
construction are needed to better define the geometry of the aquifer
system. Aquifer
tests, response tests, water-use monitoring, water-level monitoring,
and water chemistry analyses are needed to define the hydrogeology
and better define aquifer properties and will be used to evaluate
aquifer vulnerability. New project data along with groundwater/surface-water elevation data from recent studies throughout the area
will be used to construct a groundwater flow model. A pilot
project may be possible in partnership with the city of Billings to
assess the potential of developing storm-water recharge basins as a
method of groundwater recharge.
Project Number 28 Project Name: East Billings development (Huntley
to Worden)
Primary MBMG-GWIP Staff: Unassigned
County: Yellowstone
Approximate Area (square miles): 36
Drainage Name(s): Yellowstone River valley
Problem Statement: Population growth in Yellowstone
County, centered around Billings, is expanding suburban development
east toward Huntley. As a consequence of population growth in
the Yellowstone River valley, irrigated farmland is being converted
into small subdivision lots of various sizes. The farmland in
these regions has a history of over 100 years of intense irrigation. The
irrigation has created a situation referred to by some as “incidental
recharge”: creating aquifers through artificial recharge. The
shallow aquifers are now the source of water for many domestic wells
in the subdivisions. Continued reduction in recharge by pavement
and reduced irrigation application will lower the water table and
reduce the water available to wells.
Project Elements: The project will
be designed to evaluate aquifer recharge mechanisms, storage, and long-term
yield, interpretations that will allow better decisions on future groundwater
utilization. In east Billings, aquifer characterization has been
documented by monitoring of private wells, water-quality samples, and
stream/ditch flows. Additional data are needed from dedicated
monitoring wells, drilled to specific depths at selected locations. All
available data will be used to create a conceptual model. A digital
groundwater flow model will then be created and calibrated to the
data. The model will then be used as a tool to help understand
aquifer trends in similar incidental recharge areas.
Project Number 29 Project Name: Enhanced
groundwater storage/aquifer storage recovery in underground mines
near Roundup
Primary MBMG-GWIP Staff: Unassigned
County: Musselshell
Approximate Area (square miles): 20
Drainage Name(s): Musselshell River
Problem Statement: Groundwater and surface-water
shortages are typical in the Roundup area. In the 1980s
the Lower Musselshell Conservation District initiated a study of abandoned
underground coal mines along the river valley in an effort to help
alleviate shortages in the Musselshell River. It was determined
that about 17,000 acre-feet of water is in storage, and that some of
the mines are in hydrologic communication with the river alluvium. However,
further testing was halted at that time due to the presence of trace
concentrations of pentachlorophenol in the water from one monitoring
well. Since that time, better treatment and analytical tools
have been developed that may allow this concept to move forward. However,
interaction between shallower aquifers and the mine pools will require
modeling to determine possible impacts.
Project Elements: Several dedicated monitoring
wells will be installed into the mine voids and the overlying aquifers. These
will be equipped with data loggers and will be sampled for isotopes and
organic and inorganic constituents. A digital model will be developed
to evaluate current routes of recharge to the mine voids and the potential
impacts to local water users of fluctuating water levels in the mine
voids. Ultimately, the mines could be recharged during high flow
periods by the Musselshell River, as they are lower than the river. Water
will be withdrawn by pumping from the mines and discharging to the
river, allowing a significant reservoir increase without loss to evaporation.
Project
Number 30 Project Name: Flaxville/Quaternary Terrace Aquifer System (Opheim/Larslan)
Primary MBMG-GWIP Staff: Unassigned
County: Valley/Roosevelt
Approximate Area (square miles): 100
Drainage Name(s): Porcupine Creek/West Fork Poplar
River/Missouri River
Problem Statement: Significant irrigation
development has occurred in this area and there is an increasing demand
for additional development. Ancestral Missouri River gravels of the Flaxville
Formation and younger Quaternary deposits form an aquifer ranging from
20 to 100 feet thick across much of this area. The aquifer system
is dissected by surface drainages, resulting in a number of isolated
aquifer systems. The current water use is significantly less
than the original development because of conversion from low-efficiency,
high-pressure pivots to more efficient low-pressure pivots. A
better understanding of the hydrogeologic conditions is needed to maximize
use of existing water resources without depleting surface-water resources.
Project Elements: Drilling and well
construction are needed to better define the geometry of the aquifer
system. Aquifer
tests, response tests, water-use monitoring, water-level monitoring,
and water chemistry sampling/analyses are needed to define the hydrogeology
and better define the hydraulic connection between the aquifers and
wetlands. New project data along with groundwater/surface-water
elevation data from recent studies throughout the area will be used
to construct a groundwater flow model. The ultimate goal will
be a detailed aquifer management model that could be used to predict
development impacts.
Project Number 31 Project Name: Clear Lake
Aquifer System
Primary MBMG-GWIP Staff: Unassigned
County: Sheridan
Approximate Area (square miles): 60
Drainage Name(s): Big Muddy
Problem Statement: Significant irrigation
development has occurred in this area because of cooperation between
the U.S. Fish and Wildlife Service and the Sheridan County Conservation
District that resulted in a groundwater reservation. Aquifer monitoring
has been the key to this cooperation and is planned to be continued
indefinitely. Additional aquifer definition needs to be accomplished
to provide data to allow additional development without impacting water
bodies and migratory bird habitat managed by the Medicine Lake Wildlife
Refuge.
Project Elements: Drilling and well
construction are needed to better define the geometry of the aquifer
system. Aquifer
tests, response tests, water-use monitoring, water-level monitoring,
and water chemistry sampling/analyses are needed to define the hydrogeology
and better define the hydraulic connection between the aquifers and
wetlands. New project data along with groundwater/surface-water
elevation data from recent studies throughout the area will be used
to construct a groundwater flow model. The ultimate goal will
be a detailed aquifer management model that could be used to predict
development impacts.
Project Number 32 Project Name: Lower
Yellowstone Buried Channel Aquifers (Sidney)
Primary MBMG-GWIP Staff: Unassigned
County: Richland
Approximate Area (square miles): 70
Drainage Name(s): Yellowstone River
Problem Statement: A buried-channel
aquifer from 1 to 4 miles wide by 26 to 40 miles long underlies the
Yellowstone Valley through Richland County. Recharge appears to be dominated
by artificial recharge associated with flood irrigation. Aquifer
is a significant source for stock, domestic, industrial, and community
supplies. There is a significant need to understand and manage
this resource to protect existing supplies and surface-water resources
while developing additional water for communities, agriculture, and
industry. Since this aquifer is artificially recharged, changing
land uses and methods of water distribution may significantly impact
the aquifer and existing water resources. One goal will be
to define important recharge areas and mitigate land-use and operational
changes in these areas to maximize recharge.
Project Elements: Drilling and well
construction are needed to better define the geometry of the aquifer
system. Aquifer
tests, response tests, water-use monitoring, water-level monitoring,
and water chemistry sampling/analyses are needed to define the hydrogeology
and better define aquifer properties and will be used to evaluate
aquifer vulnerability. New project data along with groundwater/surface-water elevation data from recent studies throughout the area
will be used to construct a groundwater flow model.
Project Number 33 Project Name: Coalbed
Methane Groundwater Model
Primary MBMG-GWIP Staff: Unassigned
County: Big Horn, Rosebud, and Powder River
Approximate Area (square miles): 20 mi² for modeling;
100 mi² for isotope analyses
Drainage Name(s): Squirrel Creek and Hanging Woman
Creek, Powder River
Problem Statement: Development of coalbed
methane reserves in southeastern Montana and northeastern Wyoming requires
the extraction of large amounts of groundwater from coal aquifers. Groundwater
resources in Montana stand to be impacted by development in both states. Sources
and rates of recharge for these aquifers are not understood; therefore
long-term implications for the withdrawal of groundwater are not known.
Project Elements: As part of ongoing
work, water-level and general water-quality data have been collected
in this part of Montana for several decades. Monitoring wells and methane production
wells will be sampled for carbon and other isotopes, which will help
fingerprint the sources of recharge for water withdrawn during coalbed
methane production. General chemistry, isotope data, and water-level responses will be combined to generate conceptual models for
two specific areas: Squirrel Creek area, encompassing late stages of
methane production and near a recharge area; and Hanging Woman Creek
area, in the center of the Powder River Basin where aquifers are generally
deeper and production is in the earlier stages. The conceptual
models will be used to build digital models that will be calibrated
against monitoring data. Modeling of these data will help define
areas and extent of aquifer drawdown due to future development, and
identification of recharge potential. Additional monitoring wells
may be installed as data gaps are identified. Additional sites
that require models will be identified in the future, and results of
this work will be transferred and updated to those sites.
Project Number 34 Project Name: North Fork Flathead River
Primary MBMG-GWIP Staff: Unassigned
County: Flathead
Approximate Area (square miles):
Drainage Name(s): North Fork Flathead River
Problem Statement:
Project Elements:
Project Number 35 Project Name: Lower Beaverhead
West — Fact Sheet
Primary MBMG-GWIP Staff: Ginette
Abdo (406.496.4152), Julie Ahern Butler (406.496.4854), Dean
Snyder (406.496.4882), Todd Myse (406.496.4838),
Jane Madison(406.496.4865)
County: Beaverhead
Approximate Area (square miles): 110 square miles
Drainage Name(s): Beaverhead River
Problem Statement:The Lower Beaverhead River ‐ West project area is north of Dillon and extends downstream to Beaverhead Rock. The mainstay of the economy in this area is agriculture which is supported by groundwater and surface water irrigation. The Beaverhead River basin has been closed to new surface water appropriations since 1993. Groundwater permit applications must include a hydrogeologic assessment that evaluates whether the
proposed appropriation will result in a net depletion of surface water.
Project Elements: This investigation will provide more detailed hydrogeologic information in order to better understand the
effects of pumping high capacity wells on groundwater and surface water. Data collection will include well and test‐hole drilling, aquifer testing, water‐chemistry sampling and monitoring groundwater and surface‐water.
A numerical groundwater model will be used to predict impacts of groundwater development on the
Beaverhead River and its tributaries and stream depletion mitigation scenarios.
Project reports: Montana AWRA Annual Conference – Ocober 2011
Final Presentation to Beaverhead Watershed Committee–
Beaverhead River Valley West – November 2012
Project Number 36 Project Name: Big Sky
Primary MBMG-GWIP Staff: Unassigned
County: Gallatin/Madison
Approximate Area (square miles):
Drainage Name(s):
Problem Statement:
Project Elements:
Project Number 37 Project Name: Boulder River — Fact Sheet
Primary MBMG-GWIP Staff: Andy Bobst –Project Manager (406.496.4409)
County: Jefferson
Approximate Area (square miles): 377
Drainage Name(s): Boulder River
Problem Statement: :It is believed that the alluvial aquifer of the Boulder River provides baseflow to the Boulder River. In its current state, the Boulder River often runs dry in the late summer, eliminating the ability to irrigate, even for senior water rights holders. As such, there are concerns that continued approval of exempt wells in the watershed will adversely impact senior water rights holders.
Project Elements:
This GWIP study will examine the flux of water between the alluvium and the river, the magnitude of impacts that would be expected from existing and potential housing developments in the watershed, and the potential for increasing water availability throughout the year. Water quality samples will also be collected from groundwater and surface waters in the study area.
Project Number 38 Project Name: Upper Madison River
Primary MBMG-GWIP Staff: Unassigned
County: Madison
Approximate Area (square miles):
Drainage Name(s): Madison River
Problem Statement:
Project Elements:
Project Number 39 Project Name: Lower Madison River
Primary MBMG-GWIP Staff: Unassigned
County: Madison/Gallatin
Approximate Area (square miles):
Drainage Name(s): Madison River
Problem Statement:
Project Elements:
 |
 |
 |
 |
