WYOMING'S WEALTH OF WATER RESOURCES AND SCARCITY ELSEWHERE
This appendix addresses the following issues: (1) water availability, water use, and water entitlements for Wyoming; and (2) potential scarcity in other states. The motivation for the investigation can be found in our attempt to understand Question 1 in the introduction: What are the forces driving the water development program? As it will hopefully become clear in reading through the appendix, Wyoming has an abundance of water for now and for needs in the near future. However, other states and in particular the downstream basin states, do not have an abundance of excess water now. It was this juxtaposition of abundance and downstream scarcity that interested us. A further motivation for the subject matter of this appendix was to lay the groundwork for the survey of Wyoming residents.
A.2 WYOMING'S WATER AVAILABILITY, WATER USE AND WATER ENTITLEMENTS
Wyoming is separated into four administrative water divisions. The first three of these divisions contain headwaters of the Missouri River. Water Division #l includes the Niobrara River, the North Platte River, and the South Platte River drainages; Water Division #2 includes the Tongue River, the Powder River, the Belle Fourche River, the Little Missouri River, and the Cheyenne River drainages; and Water Division #3 includes the Clarks Fork River, the Bighorn River, and the Little Bighorn River drainages. For the purposes of this appendix, the Yellowstone River and its tributaries are included in Water Division #3, although their water is not available for use in Wyoming for geographical as well as legal reasons. Finally, Water Division #4 includes headwaters of three river basins: (1) the Little Snake River and the Green River, which run into the Colorado River Basin; (2) the Bear River, which flows into the Great Salt Lake Basin; and (3) the Snake River and the West Teton tributaries, which form part of the headwaters of the Columbia River Basin. (See Figure A.1 for an overview.)
Table A.1 describes water availability and water use by water division. The basis of this table is a similar table in an information leaflet from the Wyoming Water Planning Program (WWPP) from June 1972 (Wyoming State Engineer's Office ). From the WWPP table, we reproduced columns (2), (3), and (4) directly, by simply adding up the figures of those rivers that belong to one water division. This assumes, that natural streamflow volume has not changed significantly since 1968. We also assumed that the total surface area of reservoirs in Wyoming did not change significantly during the same period, as well as all other factors that influence evaporation from reservoirs. Subsequently, we also retrieved the data for column (7) from the WWPP table.
Updating was necessary, though, for columns (5) and (6), which in turn changes the figures in columns (8) and (9). Since the necessary data for this procedure is available only for counties, the first step was, to relate the 23 counties in Wyoming to the four water divisions:
TABLE A.I Wyoming Average Annual Streamflows and Water Uses (Streamflow Base Period from 1948 - 1968; all figures in acre-feet/year) ________________________________________________________________ Water Streamflow Water Yield State Line Division into Wyoming within Outflow under From Other Wyoming Natural States Conditions (1) (2) (3) (4)=(2)+(3) ________________________________________________________________ Div.No.1 530,000 1,240,500 1,770,500 Div.No.2 --- 1,019,100 1,019,100 Div.No.3 446,000 6,645,000 7,091,000 Div.No.4 531,000 6,922,700 7,453,700 __________ __________ ___________ Wyoming 1,507,000 15,827,300 17,334,300 Man's Water Consumption in Wyoming Depleted _________________________________________________ Streamflow Leaving Irrigation Municipal Reservoir Total Wyoming & Evaporation Industrial (5) (6) (7) (8) (9)=(4)-(8) ________________________________________________________________ 637,600 59,100 180,000 876,700 893,800 140,400 13,900 66,000 220,300 798,800 1,086,700 15,200 106,000 1,207,900 5,883,100 392,000 129,100 38,000 559,100 6,894,300 _________ _______ _______ _________ __________ 2,256,700 217,300 390,000 2,864,000 14,470,300 ________________________________________________________________
These assignments are naturally arbitrarily, because in most cases political boundaries do not follow watersheds. Therefore, we will only mention the three most significant problems:
After this preliminary step, the updating of column (5) could begin. Data on the amount of water used for irrigation in each county or water division was not available. But from the U.S. Census of Agriculture (U.S. Bureau of the Census [1972, 1977, 1984]), the irrigated acreage in each county was known for the years 1969, 1974, and 1982. The mean of the data from 1969 and 1974 was taken to represent the irrigated acreage at the time, when the WWPP table was compiled. This enabled us, to compute 1982 water consumption for irrigation for each water division by adding up the irrigated acreage of all counties within one water division and then using the following formula:
|1982 irrigated acreage|
1972 irrigated acreage
|X 1972 water consumption for irrigation|
|= water consumption for irrigation|
The data for 1972 water consumption for irrigation is taken from the WWPP table. The results are shown in column (5).
To update the data for municipal and industrial water consumption two factors must be kept in mind: the growing population and the increasing water consumption per capita. To take care of the change in population, we retrieved data about the population of Wyoming counties in 1970 and 1980 from the Wyoming Data Handbook 1987 (Department of Administration and Fiscal Control ) and transferred the county populations into water division populations, according to the assignment described above.
Adjusting the water consumption per capita was not straightforward. The U.S. Geological Survey (USGS) publishes water use data that includes per-capita use broken down to the state level every five years (Murray ; Solley ). Thus, we had to assume the same per-capita water consumption in all four water divisions. Unfortunately, the USGS breaks down municipal and industrial water use into four categories: (1) public supply, (2) rural domestic and livestock use, (3) thermoelectric power generation, and (4) other self-supplied industrial use. Further, water consumption is given only as total water consumption, containing ground water and saline water as well as fresh surface water, but water withdrawal is broken down into these categories. So, we assumed that the portion of fresh surface water in water consumption is the same than its portion in total water withdrawal. This assumption enabled the calculation of fresh surface water consumption in each of the four water user categories mentioned above. Table A. 2 shows the results of these calculations.
By dividing the numbers in Table A. 2 by the population in 1970 and 1980, respectively, we obtained the fresh surface water consumption per capita:
This represents a dramatic increase in water use per capita within a period of only ten years. This might be partly due to an inconsistency in the USGS data about water use for thermoelectric power generation in Wyoming. The water consumption figure jumps from 5.3 to 45 mgd over this ten year period, representing an 850 percent increase. The water withdrawal figure, however, increased only by ten percent during the same period. We had to use these inconsistent figures, because other figures were not available. This might explain a part of the dramatic increase in water consumption per capita. However, the data for public supply and for other
TABLE A.2 Wyoming Surface Water Consumption ________________________________________________________________ Fresh Surface Water Consumption In million gallons/day (mgd) ________________________________ Water Use Category 1970 1980 ________________________________________________________________ Public Supply 6.12 32.20 Rural Domestic and Livestock Use 15.36 10.92 Thermoelectric Power Generation 5.3 45 Other Self-Supplied Industrial Use 1.38 6.47 Total 28.16 94.59 ________________________________________________________________
self-supplied industrial use also increase drastically, which indicates that our results are not totally unrealistic.
The final calculation of the municipal and industrial (M&I) water consumption, as it appears in Table A.1, was done according to the following formula:
|X 1970 M&I water consumption|
|=1980 M&I water consumption|
The results of this calculation, done for each water division, are shown in column (6).
The rest is straightforward: The updated columns (5) and (6) are added to column (7), which represents reservoir evaporation, which presumably did not change since 1968. These sums are shown in column (8) and represent man's depletion of streamflow. Column (8) subtracted from column (4) yields the depleted streamflow leaving Wyoming.
Table A.1 shows the quantity of water, that is flowing through and out of Wyoming. But not all of this water is available for consumptive use in Wyoming. Interstate compacts and court decrees regulate for most rivers, how much water Wyoming has to allow to cross its stateline. Table A.3 shows, how much more water Wyoming citizens could consume, in addition to the amount they are using now. This table is based on data made available by Donald J. Brosz, Extension Irrigation Engineer at WWRC. The numbers vary a little from those in the corresponding columns in the previous table, which is not surprising, given the randomness of stream flows during the years.
A.3 POTENTIAL SCARCITY IN OTHER STATES
There are at least two ways that the scarcity issue can be examined: (1) examination of water right prices, and (2)
TABLE A.3 Water Available to Wyoming (in acre-feet/year) ________________________________________________________________ Stream Yield Outflow Consump- Legally + Inflow tive Use Available but Unused ________________________________________________________________ Yellowstone River 2,706,000 2,706,000 0 * Clarks Fork River 716,000 690,000 26,000 424,000 Bighorn River 3,961,000 2,608,000 1,083,000 1,600,000 Little Bighorn R. 119,000 114,000 5,000 ** Tongue River 460,000 376,000 84,000 94,000 Powder River 434,000 338,000 96,000 165,000 Little Missouri R. 35,000 31,000 4,000 ** Belle Fourche R. 86,000 66,000 20,000 7,000 Cheyenne River 79,000 58,000 21,000 ** Niobrara River 7,000 3,000 4,000 *** North Platte River 1,473,000 966,000 777,000 *** South Platte River 20,000 7,000 13,000 *** Little Snake River 404,000 385,000 19,000 ) ) 455,000 Green River 1,882,000 1,536,000 346,000 ) Snake River 4,436,000 4,438,000 88,000 150,000 West Teton Tributaries 360,000 355,000 5,000 * Bear River 431,000 343,000 88,000 13,000 Total 17,349,000 14,400,000 2,949,000 2,908,000 *The water in the Yellowstone River and in the West Teton Tributaries is generally considered not available for use by Wyoming. Reasons for this are geographical barriers and legal situations. The Yellowstone River leaves the Yellowstone National Park in Montana and the West Teton Tributaries are separated from Wyoming by the Grand Teton National Park. **For the rivers that are not under compact agreements (the Little Bighorn River, the Little Missouri River, and the Cheyenne River) it is not exactly known how much additional water is available for use in Wyoming. ***Niobrara River, North Platte River and South Platte River are generally considered as fully appropriated.
projected depletions.28 In what follows two trends become obvious. First, water right prices have been increasing over time and will continue to increase. Second, basins will become depleted from individual state perspectives.
Water right prices have increased rather dramatically in the 1960 to 1980 time period. Table A.4 indicates that the value of water rights in Arizona increased from $708 to $750 per acre-foot in the 1970 to 1980 period. In southwestern Colorado, and in the Colorado Big-Thompson area, however, prices increased from $913 and $310 per acre-foot in the 1960s to over $2,000 and $3,000 per acre-foot, respectively, in the 1980s. The value of water rights in Nevada remained relatively constant during the 1960s and 1970s, but increased more than five-fold between the 1970s and 1980s. Prices for water rights in New Mexico increased from between $427 per acre-foot and $2,661 per acre foot in the 1960s to between $1,000 and $10,000 per acre-foot in the 1980s. Clearly Table A.4 suggests that water values in the western states are increasing significantly.
Water right prices can be expected to increase over time. Table A.5 presents a simple projection based upon the data presented in Table A.4. The estimates are based upon a geometric extrapolation of the increases that occurred in the 1970-1986 time period. While one cannot know the precise values from such a simple forecasting framework, the table does suggest that if the recent past is a predictor of the future that values will increase dramatically. As such, it is not difficult to infer that there will be increasing pressure on downstream states to find "new" water.
Turning to expected water deficits. Table A.6 presents a possible trend through the year 2030. Rapidly growing states
TABLE A.4 Water Rights Prices in Selected Western States: 1960s Through 1980s ________________________________________________________________ $ Per Acre-Foot, 1985 Dollars____ 1960s 1970s 1980s ________________________________________________________________ Arizona $ NA $ 708 $ 750 Colorado: Southwest 913 1,929 2,102 Big Thompson 310 1,252 3,059 Nevada 320 255 1,394 New Mexico 427- 853- 1,000- ________________________________________________________________ SOURCE: Saliba, Bonnie Colby, David B. Bush, William E. Martin, and Thomas C. Brown, "Do Water Market Prices Appropriately Measure Water Values?" Natural Resources Journal. 27(3) (Summer 1987), pp. 617-652, Table 2. NA: Not available
TABLE A.5 Water Rights Prices in Selected Western States: 1990s through 2020 ________________________________________________________________ 1990s 2000 2020 ($ Per Acre-Foot; 1985 dollars) ________________________________________________________________ (1980s) AZ 850 784 820 925 CO: S.W. 2,102 2,682 3,421 5,605 C-BT 3,059 5,978 11,683 NA NV 1.394 NA NA NA NM 1,000- 1,172- 1,269- 1,743- 10,000 11,267 12,694 16,114 ________________________________________________________________ Sources: See Sources given in Table A.4. Estimates for 2000- 2020 are extrapolations from mid-1980 values based on geometric increases during the 1970-86 periods. NA: Not available
TABLE A.6 Expected Water Deficits in Selected Western States ________________________________________________________________ 1990 2000 2010 2020 2030 (1,000 Acre-Feet) ________________________________________________________________ AZ 60-500 ---- ---- 27-434 ---- CAL 1,010 1,130 ---- ---- ---- COL 2 ---- ---- 9 ---- KS 111 93 ---- 76 64 OK 112 ---- ---- 700 ---- TX 64-800 ---- ---- 1,100-2,500 ---- UT ---- ---- ---- ---- Starts ________________________________________________________________ Sources: Arizona Water Commission ; State of California, , p. 79; State of Colorado and Bureau of Reclamation , p. 20; State of Kansas , p. 79; Oklahoma Water Resources Board , p. 154, 155; Texas Department of Water Resources , Section 3; and State of Utah , p. 15, for the listed states, respectively.
such as Arizona and California can be expected to experience water deficits in the near future.
A.4 IMPLICATIONS OF WYOMING'S ABUNDANCE AND DOWNSTREAM DEFICITS FOR THE COLORADO BASIN
The implication of the water shortages expected in these states are apparent. If such shortages and high prices, in fact develop, economic activity in those states will potentially decline and the ability to attract new industry will also correspondingly decline. As such, these states may attempt to avoid shortages and attendant high prices by attempting to enhance their supplies from other sources through legal maneuvers. This point is developed from a legal perspective in Appendix E.
It would appear that Wyoming's relative abundance of water juxtaposed with the downstream shortage scenario would suggest that any methodology for evaluation Wyoming's proposed water projects would have to consider "controlling" Wyoming's water. The issue was explored in the specific context of the Watts, Brookshire, and Cummings  report. In broadening the perspective developed in that effort, the survey reported upon in Chapter 4 and Appendix D attempted to broaden the perspective of Wyoming's potential loss of some of its water resources.
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