Experience with Deep Wells.
The city of Indianapolis is situated upon the east bank of White river, upon what is termed first bottom. This bottom or valley is bounded on the west by White river and on the east by a range of clay banks, extending from the river on the south to Fall creek on the north, and varies in width, being in some places two and one-half miles from the liver. This valley has a rich soil, underlaid with sand and gravel and varying in depth from sixty to ninety feet, is water bearing below fourteen to sixteen feet. A well put down lower has a continuous supply. This water, before the ground was honeycombed with thousands and thousands of privies, was good except in some localities, where it was contaminated by swamp water and in others by salt water.
Under this first stratum of water we have a blue clay or hard pan, which is not continuous, as we find it absent in some places, and in others twenty feet thick. The water under the blue clay is strongly impregnated with iron and the precipitates from it when used in boilers is intensely hard. As the wells are put down through this blue clay to a depth of from eighty to ninety feet, it would be natural to suppose that this water would be free from contamination, but these wells are contaminated in proportion to the first vein wells. How this pollution occurs is undetermined. Back on the clay land the water is found in pools or pockets thirty to forty feet from the surface. Under this, at a depth of ninety to 100 feet, is found what we term our second vein in the valley and is of the same character.
The valley has three distinct veins of water, number one being in the sand and gravel; number two under the blue clay, and the third in the seams of the lime rock. Of these wells in the lime rock we propose to give you our experience.
During the winter of ’91 and ’92 the Indianapolis Water Company was deprived of a supply of natural gas for fuel. For this reason it was determined by the directors to put down some wells for gas near Broad Ripple, nine miles distant. In drilling care was taken to note the water found in the wells. In the first one drilled was found water greatly resembling the Blue Lick water, Kentucky, which rose to within forty feet of the surface.
The next was put near the water’s edge of White river. This well was drilled nearly 1200 feet deep. The water rose about four feet above the low water in the river. From this well we were encouraged to make a test of four or five wells near our supply, which is on a low tongue of land at the intersection of White river and Fall creek.
The first well drilled was put down 343 feet deep and is eight inches in diameter.
We went through sand and gravel forty-five feet six inches, and then struck blue clay. This was about twenty-two feet thick. Below the clay we found a bed of fine sand fifteen feet thick. After passing through the sand we struck the lime rock about eighty-two feet from the surface. From this time on we drilled through lime rock, varying in thickness and hardness, with an occasional seam, to the depth of 261 feet. After drilling 128 feet in the lime rock, the water rose to about two feet above low water in the river and then remained stationary.
During the process of drilling we struck a stray vein of sulphur water, which was strong enough to coat the sides of the box, into which the water flowed from the well, with white crystals of sulphur. It was thought for a while that this sulphur would be sufficient to condemn the well, but the vein gradually gave out. The water of this well was exceedingly beautiful, sparkling and reflecting like diamonds. To the tast# it was soft, but the test for hardness showed it to be very hard, being a little over thirty-one degrees of hardness—Clark’s method. This you will recognize is intolerably hard. The water is sterile and would be regarded as first-class water, but has other disadvantages besides its hardness. One of the most serious is the change it undergoes. After the water from the deep wells is exposed to the light and air it begins the change that it undergoes by becoming milky. Within twelve hours it begins to clear up, and before many more hours is perfectly clear. Hut on the bottom of the bottle is a brown substance, which has l»een precipitated. After the water has gone through this process it shows nearly two degrees softer. This brown substance after a while develops life and begins a growth which would in time fill the pipes, if used altogether. Where this water is left to run out on the ground this brown substance is very slippery and slimy. The action of the water upon wrought iron isto eat it away in holes or pits like smallpox. During this burning or corroding process the surface of the pipe is as black as ink. This water to many persons is harmful, as it produces disorder to the stomach. The five wells drilled are alike in character, showing a film like oil, irridescent in the sunlight; but of this there is so very little it does not affect the character of the water or make it dangerous to drink.
* Paper read before the Milwaukee convention of the American Water-works Association, by F. A. W. Davis.
Continued on Page 160.
The most remarkable thing about the wells is the fact that they are all connected by, or through, a seam in the rock. No. 2 is 300 feet from No. I, and when valve on No. 1 is shut the water in No. 2 rises about sixteen inches. No. 3 is HOO feet from No. 1 and 1400 feet from No. 2, yet the moment you begin to close the valve of No. 1 the water in No. 3 begins to rise, and in a minute’s time it rises sixteen inches, amj No. 4, which is a mile away, responds in the same way.
We get out of the five wells—four being ten-inch wells, yield not equal—about 3,500,000 gallons in twenty-four hours, flowing into the gallery and conduit line. We mingle it with our first vein of water, and so far have seen no bad results or discoloration in either bath-tubs or wash-stands.
Our conclusions are that the water, although so cool and beautiful, is not the most desirable for a public supply. First, because of its hardness; second, its tendency to destroy wrought iron pipes, and by precipitation furnish soil for plant life ; and its tendency, with many persons, to produce disorders of the stomach. Yet, we are of the opinion that the precipitation in our supply, of the iron held in solution in the water of the deep wells, is beneficial to the same extent as if we had passed the supply through iron fillings.
The water as drawn from the faucets and submitted to chemical tests shows a high degree of excellence. The last analysis made August 19 is as follows :
PUBLIC WATER SUPPLY, SANITARY ANALYSIS,
J. N. Hurty, analytical chemist, explains the chemistry of the iron precipitation in the above water as follows :
“The iron exists in the form of ferrous carbonate, although insoluble ordinarily, is held in solution in this iustance by the carbonic acid gas which the water carries abundantly. Upon being exposed to the air the free gas escapes and the iron precipitates. The iron carbonate has a yellow-white color, and at first makes the water milky, but very shortly it decomposes, becoming ferric oxide (iron rust) and the color of the water changes to a dirty brown. Upon further standing the iron oxide settles completely, appearing upon the bottom of the vessel as a fine brick-red powder, and the water becomes again bright and clear.”