The city of Lancaster is closing in on 21st century water treatment methods for two water treatment plants originally constructed in 1933 and 1955. The 12-million-gallon per day (MGD) Conestoga and the 24 MGD Susquehanna have produced water that has met all state and federal drinking water regulations. However, facility age, impending regulations and increased demand have led the city to upgrade the existing facilities.
The city and its consultants, HDR and Herbert, Rowland & Grubic, Inc. conducted an engineering study to determine the most cost-effective alternative for upgrading the plants and found that low-pressure membranes would provide the best option. HDR is in the final phases of pilot testing four potential systems to be bid for use in Pennsylvanias largest membrane water treatment application. The winning system bid is expected to be named in early January. This project is among the nations first to retrofit older plants with low-pressure membrane technology as well as compare direct- and clarified-feed membrane systems in a competitive bidding environment.
Although membrane technology has been used for many years to purify small quantities of ultra-pure water in the beverage, pharmaceutical and electronics industries, its use for large-volume potable water has been cost-prohibitive until recently. Low-pressure membranes are revolutionizing water treatment because they provide an economical, absolute barrier from potentially pathogenic microorganisms and may reduce the amount of chemicals required for disinfection.
"Being from the pharmaceutical industry, I know how successful membranes have been in purifying water for medicines. As Mayor, I am delighted to know they can now be used to economically treat high volumes of water for the citizens of Lancaster," said Mayor Charles Smithgall. "HDRs experience was a real plus in guiding us through the pilot test and regulatory permitting."