REPORT ON CONDITION OF BANGOR WATER.

REPORT ON CONDITION OF BANGOR WATER.

FIRE AND WATER ENGINEERING on September 38 contained a description of the waterworks plant at Bangor, Me. Following is a synopsis of a chemical and bacteriological report prepared by Prof. James M. Caird, of Troy, N. Y.:

In order to fully understand the situation it is necessary to enter somewhat into the construction and equipment of the various parts of the plant. The water supply is obtained from the Penobscot river. The power for operating the plant is also obtained from the same source. The drainage area of the Endoscope river, above the waterworks intake, is about 7,700 square miles. About 70 per cent, of this drainage area is composed of forests. The drainage from numerous farms finds its way into the river, and the sewerage from several localities is also discharged into it. There are also several pulp mills on the river which discharge their waste into the water and cause it to carry, at times, considerable wood pulp. Wood pulp in considerable quantities was present in the water on five days. The composition of the water is rather peculiar for a river, in that it is always highly colored and contains little or no turbidity. The average color was 71.2 parts per million, while the turbidity was only 2.39 parts per million. The average bacteria per c. c. was 1,725, while 61.9 per cent, of the 1 c. c. samples examined gave positive presumptive tests for B. Coli-communis. During the year 1,392,821,000 gallons of water were treated. The purification of this water is very difficult and is accompanied by several peculiar chemical facts. The plant consists of the following: Low duty pumps, chemical house, coagulation basin, filters, clear water well and high duty pumping station. The low duty pumps deliver the water to the coagulation basins; after passing through the basins it is delivered, by gravity, to the filters and thence to the clear water well, from which it is taken by the high duty pumps and delivered to the consumers As the water is passing to the coagulation basins, the chemicals, sulphate of alumnin and lime are added. There are two co agulation basins, with a combined capacity of 1,500.090 gallons. A test was made to learn the time required for the water to pass through the basins and the filters. A solution of common salt was added to the water on the suction side of the low lift pump, and samples of the filtered water were collected every fifteen minutes and tested for chlorine During this time the plant was operating at the rate of 5,000,000 gallons per day, and it required two and one-quarter hours for the salt to pass through the basins and filters.