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Powder/Tongue River Basin Water Plan
IV Demand Projections
For assessing the need for water into the future, this plan has developed estimates of water
demand for each major use category out to year 2030. These estimates are discussed in detail in
technical memoranda prepared for each topic.
As with all chapters in this final plan report, explicit lists of references are not provided. Instead,
all references to reports, documents, maps, and personal communications are maintained in the
Technical Memoranda that were prepared during the current planning process. Should the reader
desire to review a complete list of references for the information presented in this chapter, the
following memoranda should be consulted.
- Irrigation Water Needs and Demand Projections
- Population Projections
- Industrial Water Needs Projections
- Recreational and Environmental Water Requirements
A. Agricultural Demand Projections
Irrigated agriculture is the largest user of water in the Powder/Tongue River Basin. The irrigated
lands analysis conducted for this study indicates that there are about 169,600 acres of irrigated
land in the Basin. Of this total, 8,300 are idle, primarily due to water delivery system problems,
and another 4,300 acres have been converted or are in the process of conversion to residential
use. Of the remaining 157,000 acres that are actively irrigated, about 15,000 are irrigated using
spreader dikes or intermittent diversions. Only about 200 acres rely primarily on groundwater as
an irrigation water supply. The remaining 156,800 actively irrigated acres are served primarily
by surface water diversions. Total surface water depletions in the Basin are estimated to be
about 183,800 acre-feet in a normal year, or 1.17 acre-feet per acre for the actively irrigated
lands with surface water diversions.
The majority of irrigated land is devoted to the production of forage crops such as alfalfa, grass
hay, and irrigated pasture. Figure IV-1 shows estimates of harvested forage acreage in the
planning area for the period from 1980 through 2000 as developed by the Wyoming Agricultural
Statistics Service (WASS).1 That figure shows that the number of acres of forage crops
harvested each year varied from a low of about 65,000 acres to a high of about 85,000 acres.
There appears to be no trend of increasing or decreasing production over time, meaning that the
annual variations are likely attributable to variables such as weather, irrigation water availability,
and cattle prices.
Harvested Forage Acreage
The distribution of harvested forage acreage by county is depicted in Figure IV-2. That figure
shows that Sheridan County is the largest forage producer in the Basin, producing an average of
53 percent of all forage harvested over the period from 1980 through 2000. Johnson County is
the second largest producer with 39 percent of the total, followed by Campbell and Natrona
Counties, each with four percent of the total.
Distribution of Harvested Forage Acreage by County
A number of reservoirs store water for irrigation purposes in the planning area, but the
availability of storage water varies among drainages. Eleven significant storage facilities deliver
irrigation to irrigators in some parts of the planning area, including the Big Goose Creek and
Little Goose Creek drainages in the Tongue River sub basin; Piney Creek and Clear Creek in the
Clear Creek sub basin; the North Fork of Crazy Woman Creek and Muddy Creek in the Crazy
Woman Creek sub basin: and the North Fork of the Powder River in the Powder River sub basin.
A complete description of these storage facilities is presented in a separate technical
Trends in Livestock Production
Over the past two decades livestock production (cattle and sheep) in the Basin has remained
relatively constant. There appear to be several interrelated reasons why this has occurred. One
limiting factor with respect to herd size is the availability of summer range on federal lands,
which constitute a large proportion of rangeland in the Basin. Both the U.S. Forest Service
(USFS) and the Bureau of Land Management (BLM) have become more conservative in recent
years with respect to the management of federal grazing allotments in an attempt to improve the
quality of the range and provide adequate forage for wildlife. There has been little opportunity
for producers with federal grazing allotments to increase their production on federal lands in
recent years, and in some cases federal grazing rights have been restricted.
In discussing the future of irrigation in the planning area, it is necessary to distinguish between
needs and demands for irrigation water. A need for additional irrigation water is an identifiable
current or future use that would enhance the economic well being of the irrigator and/or the
economy of the Basin as a whole. Demands are distinguished from needs by the fact that they
are measured in relationship to price. To give a simple example, an irrigator may need additional
irrigation water in a dry year to grow enough hay to provide winter feed for his cattle. If
additional water costs $500 per acre-foot, however, the irrigator’s demand for additional water
would probably be zero because it would be more cost-effective to either buy additional forage
from other producers or reduce the size of his herd.
In analyzing municipal and industrial water uses, needs and demands are often viewed
interchangeably. The cost of water is usually a relatively minor part of the costs involved in
developing water intensive manufacturing facilities such as electric power plants. As a result, it
can be assumed that manufacturers will demand the water that they need to expand production
over a reasonable range of prices. Similarly, municipal needs are usually assumed to be essential
and thus will be translated into demands over a reasonable price range. That convention was
used for projecting municipal and industrial demands in this planning study. Irrigated agriculture,
however, is an industry in which producers
are very sensitive to the price of water, and their demands for water can change dramatically as a
function of price.
The hydrologic modeling effort undertaken for this planning study, as well as conversations with
irrigators and water professionals, indicate that there are areas of the Powder/Tongue River Basin
that could benefit from additional irrigation water, especially in dry years. Areas of particular
need appear to be the Little Tongue drainage, some of the irrigated acreage along Clear Creek
and its tributaries, the Middle and North Forks of Crazy Woman Creek, and the Powder River
and some of its tributaries, especially Buffalo Creek. Additional irrigation water in these areas
would stabilize forage production and allow ranchers to operate more profitably. Additional
storage would also allow some operators to adjust more readily to potential future changes in the
management of federal grazing allotments.
The biggest practical problem associated with fulfilling these needs for additional irrigation
water is that the returns to forage production in recent decades have not been sufficient to offset
the costs of new water storage projects. Studies of returns to irrigation water in other parts of
Wyoming indicate that one acre-foot of irrigation water used for forage production in relatively
high altitude areas of the state can be expected to generate a $15 to $25 increase in net farm
income. The cost of developing new storage can be significantly higher than that figure even
under very favorable circumstances.
Future demands for additional irrigation water in the planning area are thus largely dependent
upon factors that might either increase the returns that Basin irrigators receive from irrigation or
reduce the cost to them of developing new storage. Possibilities for increasing economic returns
to irrigated agriculture in the Basin include diversifying cropping patterns into higher valued
crops, the possibility that hay prices may rise to the point that it would be profitable to export
hay from the Basin to other domestic markets, and the possibility that cattle prices may rise
significantly over the next 30 years.
Although there are some opportunities for diversifying cropping patterns in the Powder/Tongue
River Basin, it is doubtful that diversification out of forage production will occur on a wide
enough scale over the next 30 years to warrant significant new water development projects.
Specialty crops, such as alfalfa seed or seed potatoes, could possibly be grown in some of the
lower elevation areas of the Basin. Seed alfalfa production is moving into Wyoming’s Bighorn
Basin, where acreage has grown from 2,000 to 15,000 acres in recent years. Nevertheless, such
crops still require relatively small acreages and tend to be produced in areas that have a
competitive advantage with respect to climate and/or soils, which does not appear to be the case
in this planning area.
Some trends in the agricultural industry in the western U.S. suggest that certain types of forage
production will become more valuable in the future as cash crops. As more agricultural land is
taken from production in the future, there will be less hay production because it is among the
lower valued crops that can be grown in lower elevation areas.
Wyoming is currently a net exporter of alfalfa and Timothy grass hay. No official statistics are
available on the magnitude of hay exports from Wyoming, but some experts put the figure at
about 25 percent, and expect that percentage to increase in the future. The largest market for
Wyoming hay is now Colorado, but some producers in the Bighorn Basin are shipping hay by
rail to dairies as far away as Florida and other east coast states. The types of hay expected to be
in high demand in the future are alfalfa for dairies and Timothy hay for horses. Although alfalfa
prices have been somewhat depressed in recent years, that trend is now reversing. Timothy hay
is already bringing prices as high as $180 per ton in some parts of Wyoming and alfalfa prices in
many parts of the state now exceed $100 per ton. If future market prices for these crops stabilize
at high levels, it may become practical for some producers to develop additional storage and
expand production of these crops for export markets.
Two other events could translate into more demand for irrigation water in the Powder/Tongue
River Basin over the next 30 years, a significant and long-term increase in cattle prices and/or an
increase in the amount of financial assistance available to producers for reservoir construction
from state and federal agencies.
Cattle prices have increased somewhat in recent years as per capita beef consumption in the U.S.
has stabilized at around 67 pounds after many years of decline. But according to the Cattleman’s
Beef Production and Research Board, per-capita consumption is not expected to increase in the
future and will most likely decrease from today’s levels. The USDA, however, is forecasting a
significant increase in exports of U.S. beef over the next 10 years. The basis of this projection is
the fact that demand for high quality beef in the Pacific Rim nations is expected to increase
significantly in the future as the economies of these countries recover from the 1998 financial
crisis that affected the region.
The prospects for increased federal assistance for reservoir construction seem more remote than
the projected increase in cattle prices. Federal assistance for agriculture and new reservoir
construction has been declining in recent years, and there are no indications that this situation
will change over the planning horizon. The WWDC also has tightened its funding criteria for
new water project construction in recent years. This tightening has been primarily motivated by
budget constraints, however, and the possibility exists that more state funds may be allocated to
water development over the next 30 years than are available under current economic conditions.
One potential low cost source of irrigation water for future use is CBM production water.
Projections indicate that water production associated with CBM development in the planning
area may exceed 150,000 acre-feet annually at some point during the next 10 years. There are
several practical problems with utilizing that water for irrigation, however, one of which is the
fact that high levels of production are not expected to last more than about 10 years. Given this
relatively short duration, it is doubtful that many irrigators would be willing to make the
significant changes in their operations that would be required to put this water to beneficial use.
Water Use Projections
For the reasons discussed above, the low, moderate, and high growth scenarios for future
irrigation water demand in the planning area are based upon varying assumptions concerning the
financial returns to beef and forage production and the availability of WWDC assistance for new
Low Growth Scenario
The low growth scenario is based upon the assumptions that irrigation in the Powder/Tongue
River Basin will continue to be dominated by forage production for winter livestock feed and
that cattle and forage prices will not make sustained increases over the next 30 years relative to
reservoir construction costs. This scenario also projects no increase in state funding available for
new project construction and no change in WWDC criteria for financial assistance to project
sponsors. As a result, irrigators will probably be unwilling to make long-term financial
commitments to develop new storage following WWDC funding guidelines.
Numerically, total consumptive use of surface irrigation water is expected to remain relatively
constant at 183,800 acre-feet in a normal year.
Moderate Growth Scenario
The moderate growth scenario is based upon the reasonably foreseeable possibility that cattle
prices will increase significantly over the next 10 years as forecast by the USDA. Cattle prices
are projected to stabilize at these higher prices over the planning horizon. This scenario also
assumes that the WWDC will increase its financial commitment to new storage projects.
The combination of higher cattle prices and increased WWDC assistance will allow irrigators to
maximize use of existing storage and fund some new storage projects in those parts of the Basin
where developable sites are available. Storage in Lake DeSmet that is seldom fully utilized
under current economic conditions, and additional water could be made available from Lake
DeSmet through agreements with the Joint Powers Board that now owns and operates the
reservoir. Furthermore, previous studies have identified several small storage sites that are off
the Bighorn National Forest and which could potentially be developed if economic conditions
improve for ranchers and the WWDC provides additional financial assistance.
The moderate growth scenario assumes that a combination of increased usage of
Lake DeSmet storage plus one or two small storage projects would increase stored irrigation
water use by an average of 15,000 acre-feet in a normal year. The equivalent increase in
consumptive irrigation water use would be approximately 6,000 ace-feet annually. This scenario
also assumes that Basin-wide irrigation efficiency would increase by one percent as a result of
financial incentives, adding another 4,600 acre-feet to consumptive irrigation water use in a
normal year. As a result, total surface irrigation water use would increase from 183,800 acre-feet
under current conditions to 194,400 acre-feet in a normal year.
High Growth Scenario
The high growth scenario is based not only upon the reasonably foreseeable possibility that cattle
prices will increase over the planning horizon, but that reductions in forage production in high
growth areas of the west will drive forage prices high enough to encourage Basin irrigators to
produce more alfalfa and Timothy hay.
If forage prices stabilize at higher levels and WWDC funding is increased in the future,
additional storage could be developed in the Basin to support increased forage production. The
amount of additional storage that would be developed and the amount of additional water that
would be consumptively used under this scenario are difficult to estimate because the outcome
depends not only upon future financial returns to forage and beef production, but also upon the
cost of developing additional storage in those areas where unappropriated water is available.
The water use projection developed for this scenario is that the increase in surface irrigation
water under high growth conditions will be double the amount of the increase projected for the
moderate growth scenario. That means that the amount of irrigation water consumptively used
in a normal year will increase by 21,200 acre-feet annually relative to the low growth scenario.
That increase would bring average annual consumptive use by Basin irrigators to 205,000 acre-
feet annually. Projected future irrigation water use for all scenarios is depicted in Figure IV-3.
Summary of Consumptive Irrigation Water Use Projections
B. Municipal and Domestic Demand Projections
Municipal and domestic use projections were created by combining current use rates with
population projections for the Tongue/Powder River Basin. Current municipal and domestic
consumption is described in Chapter II.
This section presents population projections for the communities and rural areas of the planning
region for the time period from 2000 through 2030 for low, moderate, and high growth planning
scenarios. The projections also provide a basis for assessing water-based recreational resource
Current Population Estimates
The first step in developing population projections for the planning area was to estimate its
current population. Population estimates for cities and towns were taken from the results of the
2000 Census. Because the geographical boundaries of the planning area do not adhere to county
lines, it was necessary to adjust the county population estimates from the 2000 Census to
reflect only the proportion of each county that lies within the planning
area boundaries. After this adjustment, the total current population of the Powder/Tongue River
Basin is estimated to be approximately 38,400 persons.
The geographical distribution of the Basin’s current population by county is depicted in Figure
IV-4. That figure shows that almost 70 percent of the Basin’s population resides in Sheridan
County. Johnson County accounts for about 18 percent of the Basin’s population, while
Campbell and Natrona Counties each account for about six percent of the total.
Distribution of Current Population
WDAI Population Projections
The Division of Economic Analysis of the Wyoming Department of Administration and
Information (WDAI) produces population forecasts for Wyoming counties, cities, and towns.
The county population forecasts are based upon time series data from which growth rates are
derived from variables such as population, sales tax collections, and school enrollments. These
growth rates are used to forecast individual county population totals, and these county totals are
adjusted to make them, consistent with state-level population forecasts that incorporate elements
of the cohort survival and employment-drive approaches.
The Division of Economic Analysis forecasts population only 10 or fewer years into the future
because of the uncertainties associated with such projections. Its most recent projections are
through the year 2008 and are relatively conservative, a reflection of the relatively slow
economic growth that many parts of the state have witnessed in recent years. A reasonable set of
low growth rate population projections can be derived by computing the WDAI’s average annual
population growth rates for the planning area for the period from 1990 through 2008 and
extending those growth rates through the year 2030.
U.S. Census Bureau (USCB) Projections
The USCB periodically produces population forecasts for each of the 50 states using a cohort
survival approach. The most recent forecasts for the State of Wyoming are two sets of
population projections through the year 2025, the Series A and Series B forecasts.
Both series of projections indicate moderate future population growth for Wyoming based upon
migration patterns in the mid-1990s. During that period, there was a moderate influx of new
residents into some parts of Wyoming from elsewhere in the country. The effects of this
migration pattern are apparent in parts of the Powder/Tongue River Basin. The USCB
projections are based upon the assumption that this moderate rate of net in-migration will
continue into the future.
Historical Growth Projections
A third set of population projections was developed from an analysis of historical population
growth. The planning area experienced more rapid population growth during the 1990s than it
experienced during the preceding 30-year period from 1960 through 1990. A reasonable set of
high growth population projections can be developed by assuming that the absolute population
growth that occurred during the 1990s will occur in each of the three following decades through
the year 2030. Projecting this level of population growth into the future for each community and
rural area in the Basin is the equivalent of assuming that the stimuli that lead to population grow
in the 1990s, namely CBM development and lifestyle related in-migration, will continue to have
the same population growth effects for the foreseeable future.
The three methods described above were used to generate population forecasts through the year
2030 for each community and rural areas. Generally speaking, the WDAI extended forecasts
resulted in the smallest population projections, followed by the U.S. Census Bureau projections
and the historical growth projections in that order. There were some exceptions to this
generality, however, primarily because some communities have experienced population declines
that were projected to continue over the next 30 years in the historical growth scenario. In some
cases, these communities were projected to have higher growth rates (or less severe population
declines) in one of the other two scenarios.
To adjust for such anomalies, the high growth scenario for each community and rural area was
defined as the largest population forecast for 2030 generated by any of the three methods.
Similarly, the low growth scenario was defined as the lowest population forecast, and the
moderate growth scenario was defined as the middle 2030 population forecast. The results of the
low, moderate, and high growth projections for the entire planning area are presented graphically
in Figure IV-5.
Low, Moderate, and High Growth Population Projections
Municipal Use Projections
Current per capita use rates for municipal water consumption are presented in Chapter II. These
rates were applied to population projections for incorporated cities and towns in the planning
area to estimate future municipal use. It should be noted that Chapter II describes municipal
systems for some small-unincorporated areas for which population projections are not available.
For purposes of projecting future use, these unincorporated areas are included in the domestic
demand projections presented in the next section.
Projections of future municipal use are presented in Table IV-1. That table shows that the four
communities utilizing surface water supplies; Buffalo, Dayton, Ranchester, and Sheridan are
projected to need between 8,600 and 10,000 acre-feet of water annually by the year 2030. The
two communities relying on groundwater supplies, Clearmont and Kaycee, are projected to need
between about 65 and 90 acre-feet annually by the year 2030. Two other communities, Edgerton
and Midwest, are not included in the projections because they obtain their water supplies from a
regional water system in Casper, and thus do not place demands upon water resources in the
Powder/Tongue River Basin. The projections of municipal use for surface water users in Table
IV-1 are diversion requirements, not consumptive use estimates. Consumptive use for the four
communities using surface water is defined as the difference between diversions and returns to
the stream from water treatment plants. As noted in Chapter II, total surface water depletions by
municipalities in the Basin are estimated to be about 2,700 acre-feet annually. Projections of
annual depletions for the low, moderate, and high growth scenarios are 3,200, 3,500, and 3,800.
In some cases there is a small difference between the populations shown for municipalities in the
Population Projections technical memorandum and the population figures presented in Table IV-
1. This difference is due to the fact that the population figures in Table IV-1 represent “service
area” populations, whereas the population estimates in the technical memorandum adhere strictly
to municipal boundaries.
An assessment was made of whether municipal systems for the communities listed in Table IV-1
have the capacity to supply their projected future water needs. This assessment involved
comparing the peak demands associated with the projections with capacity of existing systems to
meet those peak demands. The results indicate that all of the municipal systems listed in Tables
IV-1 except Kaycee’s have the capacity to meet all future projected needs. Kaycee’s system
capacity would be exceeded only under the high growth population projection scenario. It
should be noted that this finding applies only to system capacity, not water availability. Some
communities using surface water supplies, such as Sheridan, may need to acquire additional
water rights to meet projected future needs.
Municipal Use Projections
|2030 Population Projections
||2030 Use (gpd)
||2030 Use (acre-feet/yr)|
|Surface Water Users|
Domestic Use Projections
Domestic use projections were developed by first calculating the number of persons in the
planning area that are not served by the municipal systems listed in Table IV-1 and projecting
that population figure into the future. (This calculation excluded the populations of Edgerton
and Midwest, which are served by an out-of-basin water source.) Per capita domestic water
consumption rates were then applied to the population projections to estimate future water use.
The results are presented in Table IV-2 for two different daily per capita water consumption rates
and three growth scenarios. The results show that current domestic use is estimated to be
between 2,400 and 4,800 acre-feet per year. Future use projections range from a low of 2,800
acre-feet to a high of 6,400 acre-feet annually, depending upon the scenario. This water is
expected to come from ground water sources.
Domestic Use Projections
(150 GPCD-in af/yr)
(300 GPCD-in af/yr)
C. Industrial Demand Projections
Current industrial water uses in the Powder/Tongue River Basin are described in Chapter II.
This section presents projections of industrial water needs in the Basin for the period from 2000
through 2030. These projections provide a basis for gauging the adequacy of current water
supplies in the Basin to meet potential future needs. Projections were developed for low,
moderate, and high growth scenarios.
Coal-fired Electric Power Production
Currently there are no coal-fired electric generating facilities in the Powder/Tongue River Basin.
The Basin has coal and water resources to support such a facility, however, and the area has been
studied in the past as a possible site for power generation. The Lake DeSmet Energy Company is
actively pursuing a developer to use its coal reserves and water rights for power production, but
no firm proposals have been submitted to date. The company has vast coal reserves in the
vicinity of Lake DeSmet, and has storage rights for 62,000 acre-feet in Lake DeSmet and 5,140
acre-feet of storage in Healy Reservoir that could be used for power production.
There could be an air quality constraint involved in locating a generating facility in the planning
area due to its proximity to wilderness areas in the Bighorn National Forest. Whether this
constraint would be a fatal flaw depends upon a number of factors that are matters of speculation
at this time, including the plant’s design and location and the results of air quality modeling that
would have to be undertaken for permitting purposes. The area does have the advantage of
existing storage rights in Lake DeSmet that could be used to support wet cooling technology for
power production, which is in use at other facilities in the state, including the Laramie River
Station in Platte County and the Jim Bridger Power Plant in Sweetwater County. Wet-cooled
plants are usually more efficient and less costly to run than dry-cooled plants such as the
Wyodak facilities near Gillette, but their water requirements are much larger.
Another potential source of water for power production is low-cost groundwater from coal-bed
methane (CBM) production. The process of extracting methane gas from coal seams produces
large quantities of water that must be disposed of in some fashion, and use of that water for wet
cooling in electric power production would be a logical way to make use of water that would
otherwise be re-injected into aquifers, stored in small reservoirs, or discharged into streams.
There are problems with implementing such a proposal, however. One problem is the fact that
although the production life of coal-bed methane resources in the Basin is not known with
certainty, resources may be depleted in a shorter time frame than the 50-plus year life expectancy
of a coal-fired generating facility. Also, that water production from coal seams tends to peak
when the seam is first tapped, and then drop off dramatically as methane production increases,
meaning that there is a great variation in the amount of water produced at one location over time.
Projections of future water needs for electric power generation are described below for low,
moderate, and high growth scenarios. These projections are based upon the assumptions of wet
cooling technology and surface water utilization.
Low Growth Scenario
The low growth scenario assumes that no electric power generating facilities will be built in the
planning area over the next 30 years. This scenario is equivalent to assuming that (1) the
competitive advantage that other areas have held in power production in the past will continue in
the future, or (2) air quality constraints will be too restrictive to site a facility in a desirable
Moderate Growth Scenario
The moderate growth scenario for electric power production assumes that air quality constraints
on power generation can be overcome and that the availability of coal and the water resources
needed for wet cooling technology will be attractive enough for a power generator to build a
1000 megawatt (MW) facility in the PTRB sometime during the nest three decades. The
industrial water requirements for this scenario are 17,000 acre-feet annually.
High Growth Scenario
The storage rights available in Lake DeSmet should be large enough to support 2000MW of
coal-fired electric power generation using wet cooling technology. The high growth scenario for
electric power production thus assumes the relatively low cost water available for power
production in Lake DeSmet will be used to generate 2000MW of power sometime during the
next 30 years. The industrial water requirements for this scenario are 34,000 acre-feet annually.
Future electric power generation water use projections for all three growth scenarios are
presented graphically in Figure IV-6.
Electric Power Water Demand Projections
Most of the active coal mines in northeastern Wyoming are located in the Belle Fourche
and Cheyenne River Basins to the west of the Powder River. The one large active
surface coal mine in the planning area is the Spring Creek Mine Operated by Kennecott
Energy in northern Sheridan County. This mine produces approximately 11.3 million
tons of coal annually, or about three percent of the 338 million tons of coal that were
mined in Wyoming in 2000.
Surface coal mines use water primarily for dust abatement and reclamation, with lesser
amounts used for equipment wash-down and domestic purposes. The primary sources of
water for most mines are dewatering wells drilled into the coal seam ahead of advancing
pit operations and sump wells to remove water from the pit. A few mines are extracting
dry coal, however, and have drilled groundwater wells away from the coal seam to meet
Future water use by the coal industry in the Powder/Tongue River Basin is expected to
increase slightly for two reasons. First, the Spring Creek Mine may expand production in
the future if coal prices remain firm at current levels or increase. Second, some
additional mines may be opened in the future to supply coal for electric generating
facilities either in or out of the Basin. Nevertheless, most mines will continue to meet
their relatively small operational water needs from groundwater sources on site. These
activities are not expected to affect either surface water resources or other groundwater
users in the Basin. Thus, water requirements for the mining industry have not been
projected into the future.
Oil and Natural Gas Production
Traditional oil and gas production in the Powder/Tongue River Basin has been declining
in recent years. According to the Bureau of Land Management, the number of wells
plugged is expected to exceed the number of wells drilled each year for the foreseeable
future. This trend will be offset by an increase in CBM production as discussed in the
Very little water is consumptively used by the oil and gas industry in the planning area;
only small amounts are consumed for domestic purposes and to create drilling mud.
Pumping operations generally produce water as a by-product of oil and gas production.
This process water can be re-injected or discharged (with appropriate permits) depending
upon circumstances. Water flooding operations are sometimes carried out on mature
fields to increase production. In such cases, water wells can be drilled to provide
flooding water. There are about 240 such wells in the Powder/Tongue and Northeast
Wyoming River Basins combined.
In summary, water use by the oil and gas industry is generally non-consumptive, is
spread over a large geographic area, and typically does not impact either surface water
resources or other groundwater users in the planning area. For these reasons, future
requirements for this industry have not been quantified.
Coal-bed Methane Production
Coal-bed methane production has become widespread in Powder/Tongue River Basin
over the past few years, and is expected to increase dramatically in the future. CBM
development is not a consumptive user of water resources, but produces groundwater as a
by-product of gas production. The process involves pumping water from coal seams to
relieve pressure on methane gas so that it can be captured at the surface. The availability
and disposal of CBM process water presents both problems and opportunities in the
formulation of a water plan for the Basin.
Projected water production for Powder/Tongue River Basin CBM wells is depicted in
Figure IV-7 for the period from 2001 through 2020. That figure shows that produced
water is expected to reach a peak of about 190,000 acre-feet annually by the year 2005.
Production is expected to remain at that level for about five years, and then drop off to
less than 25,000 acre-feet annually by the year 2019. The projected dramatic drop off in
CBM production water after the year 2010 poses problems for the potential use of CBM
production water for industrial purposes such as electric power generation. Most large
industrial facilities have design lives of 35 to 50 years or longer, while the projections
show that large amounts of CBM will be available for only a relatively short period.
Projected Annual CBM Water Production
Coal Conversion Facilities
Several companies have studied the possibility of building coal conversion facilities in
the Campbell County over the past 20 years. There appear to be two rationales for such
facilities. One rationale is the fact that coal contains a high percentage of water by
weight, meaning that eliminating or reducing the water content of coal prior to shipment
could mean substantial savings in transportation costs to out-of -state utilities and other
users. The second rationale is that the vast coal reserves of the region could be used to
produce synthetic versions of fuels such as gasoline if petroleum prices were to increase
or government programs were in place to stimulate domestic energy production.
If coal conversion facilities were constructed in Wyoming during the next 30 years, they
would more likely be sited in the Belle Fourche River Basin than in the Powder/Tongue
River Basin because there are more active coalmines in the Belle Fourche Basin.
Nevertheless, it is not improbable that some type of coal conversion facility might be
sited in the Powder/Tongue River Basin over the planning horizon of this study. One
reason is that as energy related industrial activity increases in the Belle Fourche River
Basin, some activity may be forced to other locations for air quality considerations. For
that reason, the high growth scenario for industrial water use assumes that one coal
conversion facility designed to produce solid boiler fuel from coal will be constructed in
the planning area by the year 2030. The water requirements for such a facility would be
approximately 1,000 acre-feet annually.
Other Potential Future Uses
The industrial water use projections described above focus on existing industrial uses or
those that have been proposed but not implemented in the past. The potential for other
water-intensive industries, not discussed above, to relocate to the Powder/Tongue River
Basin over the next 30 years also warrants discussion.
According to the U.S. Department of Commerce, four industry groups in the United
States account for over 95 percent of all industrial water use. Those industries are (1)
electric power producers, (2) chemical and allied products manufacturers, (3) primary
metals producers, and (4) paper and allied products manufacturers. Electric power
producers alone account for over 80 percent of all industrial water use in this country
each year. The other three industrial groups account for roughly 14 percent of all
industrial water use.
Projections of future water requirements for electric power generators are discussed
above. The other three water intensive industries, chemicals, primary metals, and paper,
tend to locate in areas close to their primary inputs. The fact that none have located in
the Powder/Tongue River Basin in the past is an indication that commercially viable
resources needed for their manufacturing operations are not present on a competitive
basis compared to other regions of the country. Although this situation could change in
the future as resources are exhausted elsewhere, such developments are not foreseeable at
Summary of Findings
The largest demand for industrial water in the Powder/Tongue River Basin over the next
30 years is expected to be associated with the construction of new coal-fired electric
generating facilities. A smaller amount of water will be needed for facilities that convert
coal to alternative fuels. The most likely source of water for such facilities is storage in
Lake DeSmet. That storage is owned by the Lake DeSmet Energy Company and by the
joint powers board that is now operating the reservoir on behalf of Campbell, Johnson,
and Sheridan Counties.
Projections of total future industrial water use in the planning area are given in Figure IV-
8. That figure shows that for the low growth scenario, no additional industrial water use
is projected beyond the small (unquantified) amounts employed in coal mining and oil
and gas activity. For the moderate growth scenario, a projected 17,000 acre-feet would
be utilized annually for wet cooling of a 1000MW coal-fired electric generating facility.
For the high growth scenario, 34,000 acre-feet annually would be used for power
generation and an additional 1,000 acre-feet would be utilized in a coal conversion
facility, bringing total water requirements to 35,000 acre-feet annually.
Total Industrial Water Demand Projections
D. Recreation Demand Projections
Current Recreation Activity
The most popular water-based recreational activity in the Powder/Tongue River Basin is
fishing. Figure IV-9 shows that about 53 percent of Basin residents participate in fishing.
The second most popular water-based recreational activity among residents is waterfowl
hunting, followed by power boating, rafting and canoeing, and sailing.
Resident Participation in Water-based Recreational Activities
The WGFD provided estimates of the number of annual activity days of angling and
waterfowl hunting in the Powder/Tongue River Basin. Stillwater fishing on lakes and
reservoirs in the Basin accounts for 132,000 activity days annually. About one-third of
this activity occurs on Lake DeSmet. Much of the remaining stillwater fishing activity
occurs on alpine lakes and reservoirs, which are concentrated on national forest lands.
Stream fishing in the Basin accounts for about 140,000 activity days annually. The upper
reaches of many of the streams in the Basin provide very good trout fishing opportunities.
The most popular areas for stream fishing in the Basin include the Tongue River, Clear
Creek, the Powder River, and Crazy Women Creek.
Waterfowl hunters spend about 2,000 days annually in the pursuit of ducks and geese that
inhabit or pass through the Basin. Activity day estimates are not available for other
water-based recreational pursuits, including boating, water skiing, rafting, canoeing,
sailing, and wind surfing.
Future demands for recreational water resources in the planning area depend upon
numerous factors, including population growth, tourism growth, and participation rates in
various water-based recreational activities. Future participation rates depend upon
changes in preferences over time as well as the availability of water resources and the
amount of congestion encountered at recreational sites. Changes in future recreational
preferences are hard to predict, so the projections described in this section are based upon
the assumption that participation rates remain constant over the planning horizon. This
assumption means that projected recreational demands are proportional to growth in
population and tourism in the Basin. The potential effects of congestion on future
recreational water uses are discussed in the following section.
Projections of population growth in the Powder/Tongue River Basin are described earlier
in this chapter. Those projections are summarized in Table IV-3 in terms of average
annual growth rates for the low, moderate, and high growth planning scenarios. Table
IV-3 also gives projections of tourism growth over the planning horizon for low,
moderate, and high growth scenarios.
Projected Annual Growth Rates: Population and Tourism (2000-2030)
||Average Annual Growth Rate|
The other information needed to project future recreation demand is a breakdown of
recreational activity between residents and nonresidents. No precise estimates exist, but
based upon what information is available and the judgment of professionals in the
WGFD, it was assumed that 80 percent of future hunting and fishing activity would be by
Wyoming residents and 20 percent by non-residents.
This information was used to project future recreational activity days over the 30-year
planning horizon from 2000 to 2030. Those projections are given in Table IV-4. The
demand for stillwater fishing in the planning area is projected to expand significantly
over the next three decades. Similar increases are projected for stream fishing demands.
The demand for waterfowl hunting is also expected to increase over the planning horizon,
but at a lesser growth rate than for fishing.
Current and Projected Water-based Recreational Activity Days
||Activity Days by Scenario
Adequacy of Existing Resources to Meet Projected Demands
The WGFD in the past has estimated the supply of water resources available to meet the
demands of fishermen in various regions of the state. These supply estimates were
expressed in terms of fishermen days, and reflect the amount of pressure that the
Department believed at that time (1988) that publicly accessible fisheries could withstand
without significant deterioration. Although these estimates have not been updated in the
past decade, they serve as one benchmark for judging the capacity of fisheries in the
planning area to meet projected future demands. Unfortunately, the WGFD did not
estimate fishery supplies separately for the Powder/Tongue River Basin, but for an area
including the Powder/Tongue, Little Missouri, Belle Fourche, Cheyenne, and Niobrara
River Basins. Nevertheless, it is useful to review these supply estimates as background
for assessing resource adequacy.
According to the WGFD, the Powder/Tongue and Northeast Wyoming planning areas
combined provide an annual supply of 405,000 activity days of fishing opportunities.
With the exception of Keyhole Reservoir, almost all of this supply is located in the
Powder/Tongue River Basin. When this figure is contrasted with a current utilization rate
of 272,000 activity days in the Powder/Tongue Basin, it is apparent that there is no
current overall shortage angling opportunities. Individual water may experience
overcrowding at times, however, because they are easily accessible.
The projections of future demands for fishing opportunities described above range from
328,000 to 429,000 activity days annually by the year 2030, depending upon the growth
scenario used. These demand scenarios indicate that fishing pressure demands may
approach the supply of resources available in the Powder Tongue River Basin over the
next 30 years. The implications of this conclusion are limited by the fact that there is a
relatively fixed supply of streams in the Basin that are suitable for maintaining
recreational fisheries. One inference that can be drawn is that future activities that would
denigrate existing recreational stream fisheries could have significant negative
recreational effects, while activities that enhance fisheries habitat could have significant
Another inference that can be drawn from these projections is that private landowners
who control access to good quality stream fisheries in the Basin own a valuable asset and
may be able to derive income in the coming decades by allowing access to those
fisheries, either through private leases, leases to public agencies such as the WGFD, or
through daily access fees.
The other water-based recreational pursuit for which demand projections were developed
is waterfowl hunting. Those projections indicate that demand is expected to ride from a
current level of 2,000 activity days to between 2,300 and 2,700 activity days by the year
2030. The WGFD has not estimated the supply of waterfowl hunting opportunities in the
Basin, partially because populations are migratory and hunting seasons and bag limits are
established in accordance with guidelines established by the U.S. Fish and Wildlife
E. Future Environmental Water Requirements
Current environmental uses of water in the Powder/Tongue River Basin are described in
Chapter II. Those uses include:
Unlike recreational water requirements, environmental water requirements are not
necessarily related to changes in population or tourism. Instead, environmental water
requirements are at least partially a function of human desires concerning the type of
environment in which people want to live. These desires are expressed in many ways,
including environmental programs and regulations promulgated by elected
representatives at the state and federal levels. Thus, future environmental water
requirements in the Powder/Tongue River Basin will be determined, at least partially, by
existing and new legislation dealing with environmental issues at the state and federal
levels, and how that legislation is implemented by federal and state agencies.
- instream flows and reservoir bypasses;
- minimum reservoir pools; and
- maintenance of wetlands, riparian habitat, and other wildlife habitat.
Examples of such legislation include Wyoming Statutes S41-3-1001 to 1014, which
stipulate that instream flows are a beneficial use of Wyoming’s water and specify
procedures for establishing such flows using unappropriated water. This legislation
authorizes the WGFD to specify stream segments and flow requirements for an instream
flow filing. The WWDC is authorized to file an instream flow application with the State
Engineer and perform hydrologic analyses on filings recommended by the WGFD. The
State Engineer can then issue a permit for an instream flow water right following a public
Future water requirements for instream flows in the Powder/Tongue River Basin (and
other river basins throughout the state) depend largely upon how Wyoming’s instream
flow legislation is implemented over the 30-year planning horizon. Projecting the
outcome of this process quantitatively would be difficult, and is perhaps unnecessary
because instream flows and other environmental water uses are largely non-consumptive.
Instream flow designations can conflict with potential new out-of-stream uses at specific
locations, however, a topic that is discussed below.
Instream Flows and Reservoir Bypasses
Wyoming’s instream flow statutes recognize the obvious economic fact that
Powder/Tongue River Basin water resources have value in non-consumptive uses such as
instream flows. Such flows not only contribute to aesthetic character and biological
diversity of the Powder/Tongue River Basin, they also support recreational fisheries that
are important to Basin residents and to the Basin’s economy.
The WGFD has a goal of maintaining and enhancing existing fisheries in the
Powder/Tongue River Basin through the statutory designation of instream flow segments
and other management strategies. To date, a total of three applications involving six
stream segments in the Little Bighorn, Tongue, and Powder River Drainages have been
filed with the State Engineer. The extent to which current filings and future instream
flow requests may conflict with potential storage developments for supplemental
irrigation water in the Basin is unknown, but the potential for conflicts does exist. These
conflicts would have to be resolved on a case-by-case basis, weighing the potential
benefits of water to the state in instream versus out-of stream uses.
Another tool for maintaining fisheries habitat in the planning area is the provision of
minimum flow bypasses at reservoir sites. Currently, only three reservoirs in the Basin
have minimum flow bypasses included as requirements in their permitting documents;
Park, Tie Hack, and Twin Lake Reservoirs. The development of additional reservoir
storage in the future would likely bring about requests by the WGFD and others for such
minimum flow bypass requirements. As discussed elsewhere, the likelihood of additional
storage being developed in the planning area will be greatly influenced by future trends in
cattle and forage prices and state funding mechanisms available to irrigators in need of
Minimum Reservoir Pools
Another environmental water use is the provision of minimum reservoir pools for fish
and wildlife purposes. Six reservoirs in the Basin have minimum pools listed in their
permitting documents; Park, Dull Knife, Willow Park, Kearney, Cloud Peak, and Tie
Hack. Given the current federal regulatory environment and public desires to maintain
and enhance recreational fisheries in the Basin, it is likely that any additional storage
developed in the future will have a portion of its storage devoted to fish and wildlife
Another important environmental use of water in the Powder/Tongue River Basin is the
provision of habitat for wildlife. Wildlife habitat exists in wetland and riparian areas on
public and private lands through out the Basin, some of it occurring naturally and some of
it as a result of human activity. A tabulation of wetlands wildlife habitat areas in the
planning area has been undertaken as a part of the geographical information system
developed for this study. A description of the information in this database is contained in
a separate technical memorandum.
Three federal programs, the Conservation Reserve Program (CRP), the Wetlands Reserve
Program (WRP), and the Wildlife Habitat Incentives Program (WHIP) encourage the
development of wildlife habitat on private lands. The CRP program is administered by
the Farm Service Agency of the U.S. Department of Agriculture (USDA), and provides
incentive payments for various conservation practices that will enhance wildlife habitat,
as well as improve water quality and reduce erosion.
The WRP is administered by the Natural Resources Conservation Service (NRCS) of the
USDA. It is a voluntary program that provides financial and technical assistance to
private landowners to reestablish wetlands on their property The WHIP is also
administered by the NRCS, and provides technical and financial assistance to private
landowners interested in improving wildlife habitat on their property. None of these
programs result in significant amounts of consumptive water use. As a result, no
projections of future water needs for such programs were developed as a part of this
Direct Wildlife Consumption
There are no current estimates of consumptive water use by wildlife for the
Powder/Tongue River Basin. An estimate developed for the Green River Basin puts
consumptive use by big game and wild horses at about 500 acre-feet of water annually. A
similar figure would be roughly correct for the Powder/Tongue River Basin. This level of
consumptive use is relatively small and is not expected to change significantly over the
F. Summary of Projected Surface Water Demands
Table IV-5 summarizes current surface water uses in the planning area and projected
demands for surface water resources through the year 2030 for the three growth
Summary of Current and Projected Surface Water Uses
||Projected Use by Growth Scenario|
||(included in municipal)
||(included in municipal)
G. Future Uses as Related to Compact Allocation
A comparison of projected surface water demands with water available under the
Yellowstone River Compact is presented in Table IV-6. The comparison is broken down
into the Tongue and Powder River sub-Basins because different compact limitations
apply in each sub-basin. The Little Bighorn sub-Basin is not included in the projections
because the compact does not cover it.
Projected Use of Compact Allocation (Normal Year)
||Projected Use by Growth Scenario|
|Estimated Tounge River Depletion
|Wyoming's Remaining Compact
Allocation of Tongue River Flows1
|40,000 to 67,000
||40,000 to 67,000
||40,000 to 67,000
|Estimated Powder River Depletions
|Wyoming's Remaining Compact
Allocation of Tongue River Flows2
- These values are based on the limiting dry year conditions and include an assumed demand
for 18,702 acre-feet of water for the State of Wyoming to supplement the supply of pre-1950
water rights. The total projected increase in depletions (87,400-78,200) is within the limits of
this assumption. The remaining allocation is therefore not reduced under the moderate and
high growth scenarios assuming the expanded depletions occur under pre-1950 water rights.
- These values are based on the limiting dry year conditions.