IRRIGATION BY THE LARGE STREAMS.
Three rivers enter Great Salt Lake—the Bear, the Weber, and the Jordan, and upon their water will ultimately depend the major part of the agriculture of Utah. By a curious coincidence, the principal heads of the three rivers lie close together in the western end of the Uinta range of mountains.
The Bear River runs northward at first, and a little beyond the foot of the mountains enters the Territory of Wyoming. Swerving to the left, it passes again into Utah, and swerving again to the right returns to Wyoming. From Wyoming it runs northward into Idaho, and after making a great detour to the north returns on a more westerly line to Utah. It reënters in Cache Valley, and passes thence by a short cañon to its delta plain on the northwestern border of Great Salt Lake. Its principal tributaries are received in Idaho and in Cache Valley. Bordering upon the upper reaches of the river, there is little land available for cultivation, and the climate forbids any crop but hay. I am informed that the meadow land there somewhat exceeds two square miles in area. Where the river next enters Utah it runs for 30 miles through an open valley, the valley that contains the towns of Woodruff and Randolph. At the head it passes through a short defile, and can readily be thrown into two canals at such a level as to command the greater part of the valley, bringing about 90 square miles of land “under ditch”. For the irrigation of this amount the river is sufficient, but if the necessary water were thus appropriated, too little would remain for the use of the lands which border the contiguous portions of the river in Wyoming. These have equal claim to the use of the river, and a proper distribution of the water would assign it to the reclamation of the best selection of land in the two Territories. I estimate that such an adjustment would permit the Utah valley to irrigate 45 square miles with the water of the river. The minor streams of the valley will serve, in addition, 24 square miles. The climate is unfavorable to grain and the chief crop must be of hay.
Where the river next enters Utah it has acquired so great a volume that it is impracticable to make use of its entire amount. The portion of Cache Valley which lies in Utah can nearly all be irrigated. What is on the left bank of Bear River can be served by Logan River and other tributaries without calling on the main stream. The right bank will have to be served in connection with an adjacent tract in Idaho, and by a canal lying entirely in that Territory. The expense will be great, but not greater than the benefit will warrant. I estimate that the Utah division of Cache Valley will ultimately contain 250 square miles of irrigated land. The climate admits of the growth of wheat, oats, and corn, and such fruits as the apple, pear, and the apricot.
In leaving Cache Valley the river tumbles through a short, narrow cañon, and then enters the plain that borders the lake. The limestone walls of the cañon offer a secure foundation for the head works to a system of canals to supply the plain. Here, again, a large outlay is necessary, but the benefits will be more than commensurate. Not only will the entire alluvial plain of the Bear be served, but the valley of the Malade, as far as Oregon Springs, and the valley which extends from Little Mountain to Connor’s Spring. After deducting from these areas the land along the margin of the lake that is too saline to afford hope of reclamation, there remains a tract of 214 square miles. One-tenth of this is now in use, being in part watered by Box Elder Creek and other small creeks, and in part cultivated without irrigation.
In the following table are summed the agricultural resources of that portion of the Bear River drainage basin which lies in Utah:
| Tracts. | Square miles— | |
|---|---|---|
| Cultivated in 1877. | Cultivable. | |
| Base of Uinta Mountains | 1.6 | 2.5 |
| Yellow Creek and Duck Creek | 0.0 | 2.0 |
| Randolph Valley and Saleratus Creek | 9.6 | 69.0 |
| Shores of Bear Lake | 5.0 | 9.0 |
| Cache Valley | 50.0 | 250.0 |
| Delta Plain, Malade Valley, and Connor’s Spring Valley | 22.0 | 218.0 |
| Box Elder Valley (Mantua) | 1.1 | 1.5 |
| Total | 89.3 | 552.0 |
The entire area of the Bear River District is about 3,620 square miles, 2¹⁄₂ per cent. being now under cultivation, and over 15 per cent. susceptible of cultivation.
The Weber River runs with a general northwesterly course from the Uinta Mountains to Great Salt Lake, entering the latter at the middle of its eastern shore. The Ogden is its only important tributary. At the foot of the mountains it enters Kamas Prairie, in which it can be made to irrigate a few square miles. Thence to Hennefer, a distance of 30 miles, it is continuously bordered by a strip of farming land about one-third of a mile broad. Then it passes a series of three close cañons—in the intervals of which are Round Valley, with a few acres of land, and Morgan Valley, with 7 square miles—and emerges upon its delta plain. Within this plain are no less than 219 square miles of farming land, of which about two-fifths are now in use. A part is unwatered, a part is watered by the Ogden River and by a number of creeks, and the remainder is watered by the Weber. To serve the higher portions of the plain a great outlay would be required, and I am of opinion that the highest levels cannot profitably be supplied. Still, a great extension of the irrigated area is inevitable, and I anticipate that when the water of the Weber has been carried as far as is economically practicable, not more than 15 miles of the plain will remain unsupplied. Deducting this amount, as well as the area served by the minor streams and springs of the plain, there remain 185 square miles dependent on the Weber and Ogden Rivers. The Ogden River has also to water 8 square miles in its upper course, and the Weber 34, making a total of 227 square miles dependent on the two streams. Whether they are competent to serve so great an area may well be questioned. On the 8th of October I found in the Ogden River, at the mouth of its cañon, a flow of 115 feet per second, and three days later the Weber showed 386 feet. There was almost no irrigation in progress at that time, and the total of 501 feet included practically all the water of the streams. To irrigate 227 square miles, the rivers need to furnish at the critical season (in this case about the 10th of July) 1,450 feet, or nearly three times their October volume. Of the ratio between their July and October volumes I have no direct means of judging, and the problem is too nice a one to be trusted to the estimates of residents unaided by measurements; but indirectly a partial judgment may be reached by comparing the rivers with certain tributaries of the Jordan which were twice observed. City Creek was measured on the 5th of July, and again on 1st of September, and Emigration and Parley creeks were measured July 5th, and again September 3rd. These streams rise in mountains that are about as high as those which furnish the Weber and its branches, and their conditions are generally parallel. Their measured volumes were as follows:
| Streams. | I.—July volume, in feet per second. | II.—September volume, in feet per second. | III.—Ratio of I to II. |
|---|---|---|---|
| City Creek | 119 | 32 | 3.7 |
| Emigration Creek | 24 | 8 | 3.0 |
| Parley’s Creek | 72 | 29 | 2.5 |
The comparison is not decisive, but it seems to show that the problem demands for its solution a careful examination at the “critical season.” If the Ogden and Weber had been measured in September, as were the other streams, their volumes would probably have been found less than in October; and this consideration appears to throw the balance of evidence against the competence of the rivers to water the contiguous lands.
But if their incompetence shall be proved, it does not follow that the lands must go dry. The Bear at the north and the Jordan at the south have each a great volume of surplus water, and either supply can be led without serious engineering difficulty to the lower levels of the delta of the Weber.
In the following table are summed the agricultural resources of the Weber drainage basin:
| Tracts. | Square miles— | |
|---|---|---|
| Cultivated in 1877. | Cultivable. | |
| Kamas Prairie (northern edge) | .7 | 3.0 |
| Peoa to Hennefer, inclusive | 8.5 | 9.0 |
| Parley’s Park | 3.2 | 3.2 |
| Uptown | .5 | 2.0 |
| Echo Creek | .3 | .9 |
| Croydon | .4 | .5 |
| Round Valley | .5 | .5 |
| Morgan Valley | 6.0 | 6.9 |
| Ogden Valley | 4.1 | 8.0 |
| Delta Plain | 91.0 | 219.0 |
| Total | 115.2 | 253.0 |
The estimate of 219 miles of cultivable land on the Delta Plain includes 15 miles that will probably never be irrigated, but may nevertheless be farmed.
The total area of the Weber basin (including the whole plain from Bonneville to Centerville, and excluding the main body of Kamas Prairie) is 2,450 square miles; 4³⁄₄ per cent. of the area is now under cultivation, and 10¹⁄₃ per cent. is susceptible of cultivation.
The Jordan River is the outlet of Utah Lake, and runs northward, entering Great Salt Lake at its southeastern angle. On the right it receives a number of large tributaries from the Wasatch Range. The largest tributary of Utah Lake is the Provo River, which rises in the Uinta Mountains close to the heads of the Weber and Bear.
From the mouth of its mountain cañon the Provo enters Kamas Prairie, and it hugs the south margin of the plain just as the Weber hugs the north margin, passing out by a narrow defile at the southwest corner. At one time in the history of the prairie the Provo flowed northward through it and joined itself to the Weber. The surface of the prairie was then lower than now, and the sand and gravel which the river brought from the mountains accumulated upon it. Eventually the Provo built its alluvium so high that its water found a new passage over the wall of the valley. The new channel, affording a more rapid descent than the old, quickened the current through the valley, and caused it to reverse its action and begin the excavation of the material it had deposited. So long as the river built up its bed, its channel was inconstant, shifting from place to place over the whole plain; but so soon as it began to cut away the bed, its position became fixed and the plain was abandoned. The river now flows in a narrow valley of its own making, 150 feet below the surface of the plain. As a result of this mode of origin, Kamas Prairie slopes uniformly from the Provo to the Weber, and it would be an immense undertaking to irrigate it with the water of the Weber. But the Provo River can be returned to its ancient duty with comparative ease. A few miles of canal will suffice to carry its water to the upper edge of the plain, and thence it can be led to every part. Already a small canal has been constructed and its enlargement may convert the whole prairie into a meadow. Thus the prairie, although part of the drainage basin of the Weber, belongs to the irrigation district of the Provo.
The Provo next follows a narrow rock bound valley for 7 miles, being skirted by bottom lands that admit of some farming. It then enters Provo Valley, an opening about as large as the last, and favored by a warm climate that permits the growth of breadstuffs. Thence to Utah Valley it follows a deep, close cañon.
The volume of the Provo is sufficient to water about 100 square miles. If it be permitted to serve 28 miles in Kamas Prairie and 40 miles in Provo Valley and its adjuncts, there will remain for Utah Valley the quota for 32 miles. The minor streams of the valley, American Fork, Spanish Fork, Hobble Creek, Payson Creek, etc., will irrigate 120 miles, making a total of 152 square miles supplied with water. The total land of the valley which might be irrigated if the water were sufficient amounts to no less than 225 miles.
Thus it appears that if all available lands on the upper Provo are reclaimed, one-third of Utah Valley must go unwatered, while if none of them are irrigated, nearly the whole of the valley will be supplied. A middle course would appear most wise, and will undoubtedly be followed. A gradual extension of the canals, as the demands and means of the communities dictate and permit, will bring lands successively into use in the order of their value and convenience, and when the limit is reached and title has been acquired to all the water, the most available lands in each of the three valleys traversed by the Provo will have been reclaimed. The residents of Kamas Prairie will probably have increased their meadows so as to furnish winter hay for herds sufficient to stock the summer pastures of the vicinity; Provo Valley, having a less favorable climate than Utah Valley, will have irrigated only its choicest soils; and the major part of the river will belong to Utah Valley. The apportionment may be roughly estimated as—Kamas Prairie, 10 miles; Provo Valley and Waldsburg, 20 miles, and Utah Valley, 70 miles.
Below Utah Lake there is little inequality of volume dependent on season. The lake is a natural reservoir 127 square miles in extent, and so far equalizes the outflow through the Jordan that the volume of that stream is less affected by the mean level of the lake than by the influence of northerly and southerly winds. With suitable head works its volume can be completely controlled, and, if desirable, the entire discharge of the lake can be concentrated in the season of irrigation.
The highest stage of the lake is in July, and the lowest in March or April; and the natural volume of its outlet has of course a corresponding change. In July I found that volume to be 1,275 feet per second, and I am informed by residents that the stream carried more than one-half as much water in its low stage; 1,000 feet is perhaps not far from the mean volume. When all possible use is made of Provo River and other tributaries the annual inflow of the lake will be diminished by about one-eighth, and the outflow by a greater fraction, which we will assume to be one-quarter. (This postulates that the evaporation is at the rate of 90 inches per year for the whole lake surface.) The remaining perennial outflow of 750 feet per second, if concentrated into four months, would irrigate for that period 350 square miles. It will be practicable to include under canals from the Jordan only about 160 square miles of farming land, and I think it safe to assume that the supply of water will be greatly in excess of the demand.
At the present time the Jordan is little used, the chief irrigation of Salt Lake Valley being performed by the large creeks that flow from the mountains at the east. It will not be long, however, before large canals are constructed to carry the Jordan water to all parts of the valley that lie below the level of Utah Lake. They will include 120 square miles of farming land.
The mountain streams, being no longer needed in the lower parts of the valley, will be carried to higher land and made to serve the benches at the base of the mountains. By these means the total agricultural area of the valley will be increased to 192 square miles. Eventually, the western canal will be carried about the north end of the Oquirrh range and made to irrigate the northern third of Tooele Valley. It will pass above the farming lands of E. T. City and Grantsville, and enable the streams which irrigate the latter town to be used upon the higher slopes. The service of the Jordan will amount to no less than 40 miles and the agricultural area of the valley will be increased to about 45 square miles.
Including Tooele Valley and Kamas Prairie with the drainage basin of the Jordan, its agricultural resources sum up as follows:
| Tracts. | Square miles— | ||
|---|---|---|---|
| Cultivated in 1877. | Cultivable. | ||
| Kamas Prairie | 4.0 | 10.0 | |
| Hailstone Ranche and vicinity | 2.0 | 2.0 | |
| Provo Valley | 6.0 | 16.0 | |
| Waldsburg | 2.0 | 2.0 | |
| Utah Valley | 59.0 | 190.0 | |
| Goshen | Salt Creek | 14.0 | 16.0 |
| Mona | |||
| Nephi | |||
| Salt Lake Valley (including Bountiful and Centerville) | 89.8 | 192.0 | |
| Tooele Valley | 5.4 | 45.0 | |
| Total | 182.2 | 473.0 | |
The drainage district has an area of 4,010 miles; 4¹⁄₂ per cent. are cultivated, and 11³⁄₄ per cent. may be cultivated.
It will be observed that in these estimates the available water above Utah Lake is regarded as insufficient for the available land, while below the lake there is a superabundance of water, and yet the lower stream is only a continuation of the upper streams. The difference arises from the function of the lake as a reservoir. Below the reservoir the whole of the annual supply can be controlled, but above it I have assumed that irrigation will merely make use for the irrigating season of the quantity which flows at the critical period. If artificial reservoirs can be constructed so as to store water for use in Utah Valley, a greater area can be cultivated. With adequate storage facilities the streams tributary to the lake can irrigate in Kamas Prairie 28 miles; in Provo Valley and vicinity 40 miles; in Thistle Valley 6 miles; on Salt Creek 16 miles, and in Utah Valley 225 miles, making a total of 315 miles; and there will still escape to the Jordan enough water to serve all the land assigned to that stream. If such storage is practicable, the estimate tabulated above should show 552 instead of 473 miles of cultivable land. The region most likely to afford storage facilities lies in the mountains where the waters rise. I did not visit it, and until it has been examined I shall not venture to increase the estimate.
The following table gives a summary for the Great Salt Lake river system:
| Districts. | Areas, in square miles. | |||
|---|---|---|---|---|
| Whole district. | Under cultivation in 1877. | To be reclaimed in the future. | Total cultivable. | |
| Bear River | 3,620 | 89.3 | 462.7 | 552.0 |
| Weber River | 2,450 | 115.2 | 137.8 | 253.0 |
| Jordan River | 4,010 | 192.2 | 280.8 | 473.0 |
| Total | 10,080 | 396.7 | 881.3 | 1,278.0 |
| Ratios | 1,000 | .039 | .088 | .127 |
This region includes an eighth part of the land area of the Territory, and more than one-half the agricultural land. It is the richest section of Utah. Nearly one-third of its available land is already in use. The cost of the canals by which its cultivated lands have been furnished with water has been about $2,000,000. To complete its system of irrigation will probably cost $5,000,000 more.