13. It must be apparent that the proper conduct of the engineering works of your project involves the adjustment of matters beyond your control, and these points are brought now prominently to your notice, in order that you may be enabled to procure such legislation as may be necessary to have the difficulties removed.

14. The fact that the lake must have received a considerable supply of water by percolation during the past year, as shown in paragraph seven, is a most important point; for there is an immense territory sloping towards Tulare Lake on its south, east, and northeast sides, now lying dry and desolate, with the underground waterlevel far below the ground's surface, which some day--being irrigated -will be, as it were, a great sponge reservoir, through which the waters of irrigation, spread over during winter and spring, will percolate towards its basin.

15. It were idle to discuss, now, the probable supply to the lake from this source, for we have not the data upon which to base a calculation. Let us contemplate, however, the great body of land extending from Kern Lake to King's River-nearly one hundred miles-in width varying from twenty to fifty miles, all sloping from the foot of the Sierra towards the bottom of the basin, on grades of from four to twenty feet per mile. This great plain embraces the irrigable portion of Tulare Valley. Composed of washings from the flanks of the mountains, it is, for the most part, of a very light, permeable soil, varying in depth from five to forty feet; and, being generally underlaid by coarse sand substrata, and intersected by hundreds of ancient channels, many of which are now to be traced as sandy streaks or ridges meandering towards the lake, it is provided with wonderfully good natural drainage.

16. It has been found in many places that water equivalent to ten or twelve feet in depth, over an area irrigated, is absorbed by the first irrigation before the ground appears at all saturated.

Instances are numerous where the level of the underground waters has been raised from depths of thirty, forty, and even fifty feet, to levels within six or eight feet of the surface, by irrigation.

Water spread for irrigation upon various portions of this land has been known to wet the soil to the top almost, for upwards of half a mile away, down the slope on the plain, from the point where applied on the surface.

And the water in wells, near the border of Tulare Lake, was considerably raised during the past season when not any reached the neighborhood thereof above ground, but irrigation was going on, and to a very limited extent only, six or seven miles away up on the plains. These facts show the great capacity for water of the immense plain sloping towards Tulare Lake, and the strong tendency of waters spread thereon to percolate towards the bottom of the basin. where the lake is situated.

Furthermore, the position of the natural hydraulic grade line of the underground waters, ascertained by the depth of their standing below the ground's surface at various points whose elevation is known as compared to that of the lake's surface, where irrigation is not practiced, indicates an immediate connection and a reciprocal action between these waters and those of the lake.

17. The greater portion of this vast stretch of territory is to be wetted by the waters of irrigation. Probably a million acres will be under cultivation per annum, and in the ordinary season will receive their quantum of water from the supplies brought down by Kern, White, Tulare, Kaweah, and King's Rivers. The hydraulic pressure to establish strong underground currents of percolating waters towards Tulare Lake will be great, as all the circumstances so far observed appear to indicate..

It is safe to say that the conditions attendant upon the problem of underground supply to Tulare Lake are very favorable to the probability of a portion of the waters of irrigation used upon the plains sloping towards it ultimately reaching the lake basin through the invisible channels in the soil and subsoils, and materially adding to its supply.

During the time while this vast plain is becoming saturated with water, as irrigation works are extended, the draught upon the sources of water supply will be excessive, and drainage towards the lake not being yet perfectly established, there will be a period, other circumstances being equal, when the surface of the lake will probably recede below the level which it will maintain thereafter.

This principle of percolation on a large scale is now well established in engineering minds, and its phenomena readily recognized, as instances of its wonderful results are by no means rare.

18. It is true that the exposed irrigated lands will present a great surface from which evaporation will be continually in progress; and it is also to be remembered that vegetation will take up a portion of the waters of irrigation. But let it be borne in mind, that a great portion of the waters which in the future are to constitute the waters of irrigation in Tulare Valley, are in many years, under the natural order of things, lost to the valley by overflow into the San Joaquin River, and are not, under that natural order of things, evaporated from the Tulare Valley; and this loss, except during seasons of general inundation, will, when irrigation works are perfected, be saved to that valley. And, furthermore, the diminution of the extent of Tulare Lake which will be a consequence of a correct system, as indicated heretofore in this report, will greatly reduce the area of open water from which evaporation has during the past been active; and it is to be remembered that the rate of evaporation from this open water is greater than from the agricultural lands into which the waters will have in a great measure been absorbed.

19. Thus the problem of water supply for the West Side District reaches out until it embraces the entire subjects of the hydrography of the Tuilare basin and irrigation of the plains of that great valley. In the opinion of your Engineer it is worthy of a much more careful and extended investigation than it has been possible to make thus far.

20. From what has been learned the conclusion I arrive at is, that the Tulare reclamation project should be combined with that for the irrigation of the West Side District, as before indicated. With this modification made, in offering you my opinion on the question of sufficiency of supply, I can only reiterate the conclusion of my former report on the subject, as follows:

"While I do not wish to be understood as saying that Tulare Lake will afford an abundant unfailing supply of water for the West Side District, I have no hesitancy in asserting that in my opinion the West Side lands may be irrigated with a degree of regularity wherein the failure of an abundant supply of water for the purpose will be of rare occurrence; that Tulare Lake is the proper reservoir for the storage of water for such purpose, and, treated as a reservoir, is the source whence the chief supply should be derived."

At the same time I draw your attention to the paragraphs in my supplemental report in which it is pointed out that water for the irrigation of a great portion of the West Side District should be derived from the San Joaquin River. And I desire it understood that the phrase "abundant supply" does not mean any greater quantity of water than sufficient to place from eighteen inches to two feet of water over the surface of the lands per year-an amount about as great as other irrigation districts in the San Joaquin and Tulare Valleys will receive. There could be no question but the supply would be short in such a season as the past has been, for instance; as indeed the supply has been short throughout every irrigation district in the valleys.

21. The idea appears to have been prevalent that the word irrigation implies the continued presence of a stream of water commanding the lands at all times. It should be borne in mind that the term, throughout the greater number of the irrigated districts of the world, means an abundant supply for two or three months of each year at best, and that in nearly all great irrigated districts the canals, if not altogether dry, are subject to very low stages of water for six months of each year.

We cannot hope that the San Joaquin and Tulare Valleys, with less rainfall in proportion to the area tributary to them than most of the great irrigation districts of the world, are to be any more copiously or regularly irrigated than they; and it must be remembered further, that the West Side Irrigation District is not the most favorably situated portion of those valleys for irrigation, so far as abundance of water supply is concerned.

22. I cannot close this report without drawing your attention to the condition of matters pertaining to irrigation interests throughout the great valleys of the San Joaquin and Tulare. Wherever there are any number of canals or ditches deriving their water supply from one source, there confusion exists. There is no such thing as system in the appropriation and distribution of the waters. The intimate relations existing between irrigation and reclamation are not recognized, and, for the most part, correct engineering principles, upon which alone permanent works can be based, have been disregarded in the haste to effect some temporary benefit. The water appropriators and irrigators are not to blame for this condition of affairs. They have done the only thing which could have been done under the circumstances-appropriated the waters, and used them as best they could; in companies or associations, when they could; as individuals, when they were able to. Unity of action over the extent of territory which should form an irrigation district, is not to be hoped for, except under some wise system, supported by laws compulsory upon the few who will always negative every proposition

for extended public improvement. To the absence of this system, and of these laws alone, is the present condition of affairs to be attributed, and the result is alike detrimental to the interests of all concerned in the agricultural prosperity of the two great valleys mentioned. The State, through a scientific board, should regulate and control all matters pertaining to the appropriation and distribution of the waters of her streams and the reclamation of the swamp lands, and should at least outline the works necessary in the carrying out of each class of improvements which comprise the irrigation and reclamation systems within her borders. It behooves you, gentlemen, as the only constituted authority on the subject of irrigation in the State, to press upon the members of the Legislature at present assembled, the necessity for the enactment of some legislation which will lead to a system in irrigation and reclamation, such as I have indicated, for on such a system depends the success of your West Side Irrigation project.

Very respectfully submitted,

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WM. HAM. HALL, Chief Engineer.