Notes on Filtration.
In view of the unsatisfactory condition of the water at Bay City, Mich., the state health officials have recommended that the city erect a filtration plant. It is estimated that the initial cost will be $200,000 before it is definitely ascertained that it is impossible to obtain a pure water supply with the present system.
“The city should adopt this recommendation only as a last resort in its fight for pure water,” said Superintendent E. L. Dunbar. “I believe we can reach a permanent supply by extending the intake pipes further into the bay, where there is a freer and steadier current. This was suggested by former Mayor Evans’ citizens’ committee, which sought to solve the pure water problem, but was dropped when 1 estimated that such extensions would approximate $300,000.”
Mr. Dunbar estimates that a new intake in the course he has outlined, serving both stations, would cost approximately $200,000. A central station would, he estimates, approximate $300,000. Thus the entire outlay for the suggested improvements would be a half million dollars. With a filtration plant which, by the way, Mr. Dunbar believes unnecessary, the cost would approximate $750,000.
Chief Engineer Rienle, of the waterworks at Wilmington, Del., reports unusual efficient work by the filter plant. Each of the six beds was given one washing during January, the washing machine being in active service, but approximately 36 hours in the period of 30 days and this record is the best so far established. The biological efficiency of the plant has been 99 per cent. The collection of water rents for January amounted to $165,455.36, of about $5,000 more than for the corresponding period last year.