GROUND WATER TABLE STUDIES

Mr. THURSTON. Have you made any studies to ascertain whether or not there is a lowering of the water levels in the agricultural regions? Mr. MCCRORY. There are two types of lowering of the ground water table. There is a general rise and fall of the water table, due to fluctuation in precipitation. At the present time we are getting quite a few letters from the Middle West complaining about the fall of the ground water level. I think that is undoubtedly due to a deficiency in precipitation. The same thing happened about Washington when we had the drought here in 1929. Wells were dry at that time which had never gone dry before, yet when we got heavy rains in the winter the water table commenced to rise quite rapidly and I believe has been rising ever since.

Then, we have the other type of falling ground water table, where the demand on the underground water supply is greater than it can stand.

Mr. THURSTON. That would be in the arid or so-called "irrigation regions"?

Mr. MCCRORY. It is in both regions. A good example of that type of difficulty is the rice irrigation territory about Stuttgart, Ark, or Lake Crowley, La. In these regions the ground water table has been steadily falling and the head against which farmers have to pump has steadily increased.

There is under consideration-I do not know whether it has been approved as a public works project to supply irrigation water to a part of the Stuttgart area in order to relieve the drain on the underground water in that area. The depth there is reaching a point where the investment seems to be warranted. The same is true in southern California, where they are pumping as much as 500 or 600 feet, or were, when I last inquired.

Mr. THURSTON. Have you made any investigation of this: In the northern half of the State of Iowa, where they have the system of expeditiously removing the water, and because of the drainage ditches and the laterals, the water has been taken off more rapidly than heretofore; there is considerable complaint that they do not have sufficient moisture to supply those lands. There has been some question raised as to whether they pursued a sound policy in having these drainage ditches and laterals placed in there. Have you made a study of that?

Mr. MCCRORY. We have studied that question; it comes up very frequently, and in that part of the country, I am sure that it is due to fluctuation in the precipitation. If you get heavy winter precipitation, your underground water will rise; if you do not have a heavy winter precipitation it does not rise very much.

Mr. THURSTON. It is a matter of precipitation?

Mr. MCCRORY. Yes; a matter of precipitation.

Mr. THURSTON. And not acceleration in the moving of water by drainage?

Mr. MCCRORY. I do not think drainage has a great deal to do with it; it is largely a matter of precipitation in the winter. In the summertime, the vegetation removes the water before it has time to percolate deeply.

THURSDAY, JANUARY 25, 1934.

IRRIGATION STUDIES FOR OTHER DEPARTMENTS OF THE GOVERNMENT

Mr. SANDLIN. Mr. McCrory, we were on the farm irrigation project, were we not?

Mr. MCCRORY. Yes, sir; I have just one more brief statement that I would like to make on that project.

One other type of work that has been of considerable importance in recent years has been our work for other departments of the Government. The irrigation division during the past year has done work for the State Department in connection with the investigations on the Kootenai River, Idaho; for the Biological Survey of the Department in connection with the suit in regard to the Malheur Bird Reservation; and for the Farm Credit Administration we have made a study of the Imperial and Coachella valleys, and of the lower Rio Grande Valley, Texas, to determine on what lands, from an engineering standpoint, loans could be safely made.

engineers have acted as technical adviser to the Forest Service in connection with the erosion control work of the Civilian Conservation Corps.

FARM DRAINAGE AND EROSION CONTROL

Mr. SANDLIN. The next subitem is farm drainage and erosion control. Will you give us a statement on this project?

Mr. MCCRORY. Yes, sir.

The work under that project consists primarily of farm drainage work. We have in progress a number of projects dealing with drainage problems as they affect the farm. One of the important investigations that we have under way at the present time is a study of the flow around bends in channels and around pier noses. That was started when we were in the Bureau of Public Roads, and is now approaching completion. We have developed quite fully the laws that govern the flow around bends, a subject on which very little was known. There is a wide practical application for this information in the design of drainage channels and of bridge piers; in fact, any hydraulic structure where it is necessary to change the course of the flow of water.

Mr. SANDLIN. The Engineer Corps of the Army is interested in this, of course?

Mr. MCCRORY. We have dealt more with the agricultural phases, but there is broad application for the data. For instance, to give you a typical example, a drainage levee district may be designed by an engineer, and the stream in flood may tear out the levee. We have developed the laws that govern the flow of water in channels to the point where we know pretty well how to design them, so that if conditions permit the proper design we can design a curved channel that will be permanent in character. There are a number of instances that could be cited where large losses in drainage districts could have been avoided.

Mr. SANDLIN. That is if the levee had been constructed in another manner?

Mr. MCCRORY. If the ditch through which the stream was carried around the levee district could have been designed in a different way.

Then this information is of value in connection with the design of drainage pumping plants, where again we have the problem of passing water around bends. It has been a problem on which there has been very little information, and much of the information that we had was taken from foreign publications and had been greatly mangled in translation, as we found out when we got finally to the originals.

One of the things that have come out of that study is definite information in regard to the amount of resistance to flow in ditches and floodways that pile trestles and pile bridges offer during floods. That is a very important question. A few years ago I worked at Newport, Ark., where it was highly important from the standpoint of the city of Newport and of the railroad, to design a levee that would make the town safe against flooding. The railroad was rebuilding its line across the White River, using pile trestles, and there was no reliable information in regard to just how much retardation the trestles would offer to flood flow. The data we have obtained gives us good indications as to what happens.

The run-off investigations I have discussed frequently before, and I think it is not necessary to say anything on those at this time.

EFFECT OF SOIL ALKALIES, SOIL ACIDS, AND FROST IN DRAIN TILE

The study of the effect of soil alkalies, soil acids, and frost in drain tile is continuing. During the past year we have made considerable progress in the use of certain admixtures to tile, particularly calcium chloride. Much of the tile that is manufactured now is made in plants where they keep the temperature up to about 130 degrees during the process of manufacture, and apparently the admixture of a small amount of calcium chloride will make a tile that is highly resistant to alkalies and soil acids.

This picture [indicating] illustrates the condition after 1 year at Medicine Lake, S.Dak.

We are approaching more and more nearly a final solution on that problem of how to make drain tile of cement; which in the larger sizes is the cheapest drain tile that we know how to make at the present time; that will be resistant to soil alkalies and to the soil acids that you find in a large part of the United States.

Mr. SANDLIN. The tile manufacturers, of course, have this information? You give them the information?

Mr. MCCRORY. We are giving them the information as fast as it is available.

One of the curious things that we have developed from that study is that not all portland cements react the same to alkalies or to acids. There is a very great difference in the resistance of different portland cements. That has made it necessary to back up and study the problem in a somewhat broader way than we had originally thought necessary. But it has been a very productive study.

Mr. SINCLAIR. This tiling does not help to clear up the alkali or acid that is in the soil and make the soil sweeter, does it? Do you drain that off, too?

Mr. MCCRORY. In the irrigated regions a large amount of so-called "alkali" is removed through the drains. A certain amount is removed in the humid regions.

Mr. SINCLAIR. It does keep the soil, then, in a fresher and sweeter condition?

Mr. MCCRORY. Yes, sir. But the curious thing, and the thing that started this study, was the fact that in Minnesota, some 10 years ago, they had a wet year and there were very serious failures of large drain tile, some of which had cost $30,000 or $40,000 a mile due to the soil alkalies attacking the tile. It brought up a very serious problem as to what they should do. The concrete tile are cheaper than the clay tile in the larger sizes, and in the very large sizes it is difficult to make clay tile.

We have developed now a method of finding out where difficulty is apt to occur, and we think that ultimately we will be able to work out a concrete tile that will be so resistant to alkali and acid conditions that it can be safely used. The acid condition exists in varying degree practically over the Eastern United States.

The irrigation in the humid region I have covered before, I think, and unless you wish a further statement it is not necessary to cover it again.

DRAINAGE OF SUGARCANE LAND

The project on drainage of sugarcane land was continued during the past year. In 1933 the yield of cane on the tile-drained land showed an average increase of 51⁄2 per acre tons over the untiled land, and the area drained with open ditches 3 to 6 feet deep gave an increase of cane of 6.3 tons per acre over the undrained plot.

Mr. SANDLIN. You attribute that increase to the proper drainage? Mr. MCCRORY. That is largely due to drainage.

I think that there are considerable possibilities of improving yields of cane in Louisiana by better drainage. We are doing also some work on the irrigation of sugarcane that is showing some promise.

Mr. SINCLAIR. Do you have practical demonstrations in the cane regions?

Mr. MCCRORY. We have about 120 acres that we have the privilege of working on, on one of the plantations, where we have installed experimental drains of varying depths, and are securing drainage by pumping.

Mr. SINCLAIR. Does that information get to the farmers?

Mr. MCCRORY. As rapidly as we have anything to give them safely, we are giving it to them. We have not pushed that very much recently, because we were not quite sure what the final results were going to be; but the weight of the evidence seems to indicate that improved drainage will increase cane yields in that country. The investigation is being continued.

SEWAGE IRRIGATION IN NEW JERSEY

The next project we have is an investigation of sewage irrigation in New Jersey. The reduction in funds last year made it necessary to close that work out next spring. We have carried through 3 years' work at the station in cooperation with the New Jersey experiment station and the borough of Vineland. We have successfully disposed of the sewage in a much more economical way than I think can be done by any other type of disposal plant, and we have been able to grow crops on sandy lands that were practically inert in their

original condition. Several New Jersey State institutions are using this method of disposal.

I think the method of sewage irrigation that has been developed and used in New Jersey under the direction of our Mr. Mitchell is in many localities well suited to use by institutions, small towns, and villages. It has proven sanitary and cheap.

STUDY OF GROUND WATER IN FLORIDA

We have under way a study of the ground water in Florida, which is being carried on in cooperation with the Everglades experiment stations. The work is just well started, and we have not any definite reports to give on that job this year.

The problem of proper drainage in the peat lands of Florida and Louisiana is particularly important to the success of agriculture in that region.

STUDY OF THE OPERATION OF DRAINAGE DISTRICT

One of the other studies that we made during the year was a study of the operation of drainage districts. That work is still in progress. We have been endeavoring to find out why some drainage districts got into trouble and others did not, and how those in trouble could work out of their financial difficulties. One of the studies that we made was of the Little River District in Missouri. That is the largest drainage district, I believe, in the Mississippi Valley-about 500,000 acres. They had a very serious financial problem there. The landowners were not paying their taxes. We made a study of conditions and worked out a recommended plan which has been used in effecting a settlement between the bondholders and the district, and I believe that the Reconstruction Finance Corporation has finally made a loan-I am not sure whether the loan has been completed, but it has, I believe, been arranged for-largely on the basis of our report. The soil erosion item also covers our administrative work in the office. I think that might best be discussed later.

Mr. SANDLIN. There are practically none of these funds spent in the field; it is largely office work?

Mr. MCCRORY. It is largely office work.

Mr. SANDLIN. We will let that be discussed later.

FARM BUILDINGS

Mr. MCCRORY. In our division of structures we have been working to improve farm buildings throughout the country.

STUDY OF THE STORAGE OF POTATOES

One of the interesting studies that we have had in progress is a study of the storage of potatoes, which we are carrying on in Maine in cooperation with the Maine agricultural experiment station and some farmers in that region. We have been able to work out ways of reducing the bruising and other mechanical damages to potatoes which cause loss. We have also worked out improved methods of controlling the temperature in the large potato-storage houses that they have in that region. Our study has been of considerable practical value to potato growers throughout the country.

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