By Seth Kinker, firstname.lastname@example.org
The Chelsea City Council approved a request from Corey Davis, the Water/Wastewater Superintendent for the City of Chelsea, at their Oct. 1 meeting for the leasing of reverse osmosis membranes.
Reverse osmosis is a water purification technology that uses a membrane to remove ions, molecules, and larger particles from drinking water. A budgeted item with the Water/Wastewater department, Davis described a change in the process that Chelsea has used in the past.
In the past, they would buy 36 reverse osmosis membranes, with one membrane being replaced out of each housing for the membranes – the oldest.
Three years ago, they quit making the membranes that the City of Chelsea used. The new membranes are essentially the same, but the end connections differ meaning they won’t connect with the old membranes the city used to use. For the last three years they’ve removed an entire housing or skid for the membranes and replaced it.
This year, Davis reported that they were looking at an offer on leasing membranes. Similar to a car payment, for a period of three years with an option to send them back and get new ones or continue to use them. Davis reported that the lifespan of these membranes was 7-10 years, suggesting buying them after three years.
The Council voted to accept a quote from Process Solutions for 108 breather osmosis membranes for a total of $19,447.83 per year for three years, Davis reported that it would end up saving the city about $600 per membrane annually by doing it all at once.
Council member Cheri Albertson asked if the 7-10 year lifespan was also the frequency at which they must be changed.
“When we first started doing this our membranes were seven years old,” said Davis. “So, we replaced one membrane, the year seven membrane, and put the number six membrane forward, and every year we did that. By doing this we won’t have to buy membranes for just over five years.”