Favors Mechanical Filtration for Pittsburgh
Whether or not the use of hyperchloride of lime in filtering the supply of Pittsburgh, Pa., at Aspinwall is thoroughly efficient or detrimental to the health of those who use it, was one of the chief points of the testimony during the trial of Director Armstrong, of the department of public works, charged by the Voters’ League with malfeasance and mismanagement in office. Superintendent Finley stated that he believed the existing sand filtration plant was antiquated and that he favored mechanical filtration. There had been no change in the operation of the filtration plant, and thought that whatever improvements had been made had been “squeezed in” under the name of “contract baffles,” a term invented in order to bring it in under the term of bond issue. It was “purely a preliminary process,” but the “prime necessity was not due to the fact that only 2,000,000 gallons of water per acre through the filter bed instead of 3,000,000 or 4,000,000, as was originally intended.” The only objection against filter beds was the cost, and hired experts were called in was in order that “enough water might be furnished at a satisfactory cost to supply Pittsburgh.” The water of the Allegheny river is subject to great changes from being quite muddy to the reverse, the superintendent stated, and at times suspended particles of paraffine oil tended to clog the filters. Hence, to counteract and remedy these acid conditions of the water, experts were employed. The precipitant proposed to be used at certain times of the year was hypochloride, not as a substitute for filtration, but as a germicide to kill the typhoid fever germs. Before a man could consume one grain of hypochloride at the rate of drinking one gallon of water a day he would have to live 7,190 years. If he drank the same amount daily of Pittsburgh water, his span of life would have to be 17,000 years before he consumed a medical dose of the chemical such as is given typhoid fever patients.