The Village of Chelsea, Michigan, population of 4,200 residents, needed to upgrade or replace their existing ironremoval plant to provide additional capacity for the growth they were experiencing and toreplace old equipment and facilities. Tetra Tech MPS (TTMPS) was retained to examine the optionsfor upgrading the treatment facility and to apply for State of Michigan Drinking WaterRevolving Fund (DWRF) loan monies for the project. The first step in this process,preparation of a Project Plan, was completed in 1999. This Plan examined the options fortreatment plant upgrades. The most cost-effective alternative was the construction of alow pressure, reverse osmosis (RO) membrane treatment system for softening of thegroundwater supply. This option was compared with conventional lime softening and theexisting treatment for iron removal.Significant public input was solicited throughout the planning and design process todetermine whether the users wanted to upgrade their water treatment process from ironremoval only to softening. The public response was overwhelmingly in favor ofupgrading to softening treatment. Based on this response, the Village elected to proceedwith the membrane softening option.The Michigan Department of Environmental Quality (MDEQ) required that a pilot studybe done for all new membrane treatment plants. At the beginning of the project, therewere no other membrane softening plants in the State either in operation or design.Because of the strict funding deadlines for the DWRF program, and the Villages need toget new capacity on line as soon as possible, there was not sufficient time to conduct apilot study. Fortunately, TTMPS was simultaneously completing a pilot study for a lowpressure, RO treatment system in a neighboring community with a similar quality sourceof groundwater. Based on the results from this pilot study, the State waived therequirement for a separate pilot study for Chelsea provided that the same equipment wasused. The State did stipulate that the equipment used must have National SanitationFoundation (NSF) certification.Design of the new treatment plant began in January, 2000 and was complete by May,2000. Bidding of the project took place in the fall of 2000, with constructioncommencing in December, 2000 and completed by the summer of 2002. The plant beganproducing softened water in July, 2002. Includes tables, figures.
Keywords: Softening; Membranes; Michigan; Equipment; Iron Removal; Treatment Plants; Design; Construction; Planning
