Indispensable of life, water is generally (and too casually) accepted as “God’s gift to man”; and the need for improving the “gift” is only really appreciated when it becomes impaired in quality of quantity. It is said that a person could live at least a month without food but would die in less than three days without water. It makes up a large part of our person, (75 per cent), and is a constituent of all food. It is surprisingly abundant...so much so that if all of the earth’s mountains and ocean depths were leveled off, the entire world’s surface would be covered with water to a depth of almost two miles. While there is an abundance of water on this earth, only a very small percentage of it in its natural state, can be used for drinking. Nature itself has set the standard. The clear flowing spring of sparkling, uncontaminated water represents the ideal supply for human use. Unfortunately, Nature merely sets the standard and does not provide supplies equal to the standard sufficient for all needs. It is the job of the waterworks men to process and improve the supplies which are at hand to meet the requirements and conditions of modern living.
As most of you know, the Shannon water supply comes from Woodward Creek, located about one mile west of the filter plant. It is screened and pumped by a centrifugal pump, driven by a 50 H. P. electric motor, at the rate of about 20,000 gallons per hour. Maybe you can get a better idea about quantities by this illustration. The railroad tank cars you see on almost every freight train hold 10,000 gallons. So you see, we are pumping two car-loads an hour or a trainload of forth-eight cars each twenty-four hours the pump runs. The raw water (untreated water) is pumped from the creek through a six-inch cast iron main into the mixing basin at rear of filter plant. In this basin the water is coagulated. In the process of coagulation the individual small particles of mud are brought together by the expenditure of chemical and mechanical energy, into compact masses. The chemical energy is supplied by agitation in the mixing basin for about thirty minutes. The water then passes into the settling basin (capacity 100,000 gallons) where these compact masses, being heavier than water, will settle to the bottom of the basin, leaving relatively clear water to be filtered. These compact masses, known to us a “floc” will not form unless the ration of alum to lime in the water is correct. The correct amount of alum to be used for the formation of “floc” must be determined by laboratory test every time the muddiness of the raw water changes. The water passes from the settling basin into the filter. The filter area is 170 square feet or 13 ft. x 13 ft. the filter contains about 30 inches of graded gravel. The water passes downward through this bed of sand and gravel, emerging from the filter a clear and sparkling liquid.
The water is then treated with soda ash to prevent corrosion in the distribution system. The final treatment and the most important is sterilization. This is accomplished by the addition of chlorine. Any harmful organisms that have escaped the filter are instantly destroyed by the chlorine. The amount of chlorine required is dependent entirely upon the composition and quality of the water to be treated. The average dosage at this plant is 0.5 parts per million, or slightly over four pounds for each million gallons of water filtered. The correct amount of chlorine to use is one that will destroy harmful disease germs and still not produce an objectionable taste in the water. We have the best equipment obtainable for measuring and applying chlorine and we also make chlorine tests several times each day in our laboratory. In addition to this, we make our own bacteriological test and also send samples of water to the State Department of Health each month.
If you will excuse me for boasting, I would like to say that during the nine years I’ve been connected with the filter plant, all samples examined by the State Department of Health have been uncontaminated.
Now to get back to cases. The water, after being sterilized is stored in two clear water basins with a combined capacity of 500,000 gallons. We keep these basins as nearly full as possible at all times so as to have an ample supply on hand in case of fire or break-down to our pumping equipment. In addition to this, we have a 200,000 gallon tank in the Mill yard for fire protection. At present we are using about 300,000 gallons of water a day and every gallon of this must be carefully processed regardless of the fact that only a very small percentage is used for drinking purposes.