Deep Well Mistakes by Which Others May Profit
Some of the Problems Which Confronted a Small City in Sinking Wells—Pays to Employ Reputable Concern to Do Work
THE following article will be found of use to those superintendents who are contemplating the addition of wells to their water supply, in that the suggestions contained therein may avoid errors in judgment that are quite natural to those inexperienced in such matters:
During the past twelve years, Louisville has had considerable experience with deep wells. The troubles that we have had may serve to keep another city from making the same mistakes.
Away back in 1913, the Louisville Light & M ater Company contracted for a Layne Well 6 inches in diameter and 480 feet deep. The static level then stood at 123 feet and this 6-inch well produced 150 gallons per minute pumped by air lift. In the twelve years that have passed, the static level has gradually lowered to 150 feet. In spite of the lowering of the water level the well will produce today 75 gallons per minute but the requirements of the city passed this figure several years ago.
Pump Breaks Off Into Well
About 1916, the City bought the water and light plant from the Louisville Light & Water Company. In 1917 a contract was signed with a well driller for a 10-inch well 450 feet deep at a cost of $5,000. When the well was completed the contractor was permitted to move the well rig before the well was tested. A deep well centrifugal pump was purchased and installed in the well. It happened that the deep well pump was of the water lubricated type. When the pump was started, the well would not produce the water. As a result the pump bearings seized and the pump twisted off near the pump head, dropping the pump bowls with about 150 feet of discharge column.
During the next two years, several attempts were made to fish out the pump from the well. After spending about $2,500 for fishing jobs the pump was removed in 1919. It was then found that the driller had set the screen in the wrong place and the screen was not in the water bearing formation. The only way to get
any results from this well was to dynamite it. So several charges were placed in the proper position, and production was finally brought up to about 40 gallons per minute.
By pumping the original 6-inch l-ayne well at about 75 g. m. p. and the dynamited 10-inch well at about 40 g. p. m., the city managed to get along until 1924. The wells were pumped by air from a motor driven compressor in the winter and a steam driven compressor in the summer. This was due to the fact that the light plant was driven by oil engine in the winter time and the steam plant operated only during the summer when ice was being made.
Another Well Fails
About 1924 the city began to feel the need for more water. Contract was let for an 8-inch well 450 feet deep at a cost of approximately $5,000. The well would not produce enough water to pay to pump it. After working on the well for about a year it was abandoned.
These two wells in 1917 and 1924 had each cost us over $5,000. The deep well pump cost us $3,000 plus $2,500 for fishing it out of the well making a total expenditure for wells and equipment of about $15,000 and we had nothing to show for it. We had simply purchased two holes in the ground without specifying whether or not any water was to be produced. Various well concerns had told us that a satisfactory deep well supply could not be obtained in or near Louisville.
The citizens and taxpayers of Louisville had become so worried and disgusted with the water supply shortage that a number of them were planning on leaving the city. During the hot summer months just when the water was most needed, the water was shut off 50% of the time. So when I was elected Mayor it was on the promise that the city water supply would be improved.
Well-Drilling Company Makes Proposition
Early in 1925 an unusual proposition was offered by the Layne-Central Company of Memphis, Tenn., to produce 250 g. p. m. or receive no pay. It was agreed that this well would tie constructed at a place mutually agreed upon by the city and the contractor. As the most convenient location was near the water and light plant, the city insisted that the well IK* located there.
So the well was constructed at the water and light plant but against the recommendation of the contractor. This well produced only 100 g. p. m. so the contractor proceeded to remove the equipment and try again in another location. Just at that time the city experienced another shortage of water so we offered to purchase the 100 g. p. m. well at the cost of the material in the well which the contractor was permitted to remove under the agreement. This offer was accepted but had no effect on the original contract to develop 250 g. p. m.
New Well Proves Satisfactory
The contractor then moved to a point about seveneighth of a mile south of the plant and ran a test hole to determine conditions. Results were not entirely satisfactory to the contractor so the spot finally selected was 1 miles south of the original well. The tests here were entirely satisfactory and a 12-inch Layne well was constructed to approximately the same depth as our other wells. On test the well produced 500 gallons per minute—twice the guarantee—with only a 25foot drawdown. This figures our 20 gallons per foot of drawdown while the 1917 dynamited well produced only 2/3 of a gallon per foot of drawdown and the 1924 well did not produce at all.
This well is pumped by a 7-stage Layne Vertical Centrifugal Pump set 140 feet from the surface. The pump is driven by a 25 h. p. 1170 r. p. m. vertical motor direct connected to the pump head. This makes a smooth running unit that requires only a very small floor space.
Extra Pipe Line Works Well
Ordinarily, the extra pipe line required might be an objection but in our case it worked out quite well. There are a number of sawmills, railroad shops and residences along the pipe line so we are simply using the well pipe line as a distribution line.
We have a 100,000 gallon tower that maintains the service pressure. The deep well pump discharges at the surface and a booster pump puts the water in the tower against the service pressure. We could have used the deep well pump to put the water directly into the tower, but since we already were using surface storage at the main plant, it was decided to use booster pumps for service pressure. The present surface reservoir at the main plant has 50,000 gallon capacity.
Operating Agreement With Railroad
As soon as our well was finished, the Gulf, Mobile and Northern R. R. Company contracted for an exact duplicate and then made an operating agreement with the city of Louisville.
For a period of ten years the city is to operate the Layne well owned by the railroad and furnish a certain amount of water to the railroad which agrees to maintain the well. In return for operating the well the city is to receive all water above the quantity required by the railroad company. By this arrangement we have two duplicate well units which gives a splendid reserve capacity for both city and railroad company.
Pays to Deal With Reputable Concern
After twelve years of experience in deep well supply for the city we can truthfully state that there is only one satisfactory way of awarding such a contract; and that is to a concern that thoroughly understands scientific methods of well construction and is willing to back up their proposal with a definite “money back” guarantee.
The combined production of 1,000 gallons per minute of pure artesian well water certainly fulfills the promise made when I was selected mayor. With all this water available we are now in position to invite to Louisville any new industries that may be looking for a Southern location. If more water is required we know that more Layne units can be added to take care of the demand.
In addition to the improvements of our water supply, hydro-electric lines are now being built into Louisville and within the next year we will have power available at a very reasonable rate.