Project Background

Typically, wells have a lifespan ranging from 10 to 30 years, after which parts begin to wear out and pumping efficiency declines. Neglecting maintenance exacerbates a well's reliability issues. In 2017, the District began a multi-year rehabilitation process initiated by deferred maintenance along with other complications. Throughout the rehabilitation period, Well 14 remained offline to safeguard water quality. However, this hiatus placed additional strain on other wells within the District, particularly during hot summer periods.

Project Outcome

In 2022, the District's most productive well, Well 14, was reinstated after undergoing comprehensive rehabilitation, including the installation of a 4-log treatment. The cost of the overhaul of Well 14 was certainly substantial (approx $1.5 million) and took a long time to complete (many delays due to supply chain issues), but clearly, this newly refurbished well will be a huge benefit to our community for decades to come. This well serves are our largest-producing well, pumping approximately 1,790 gallons per minute, significantly surpassing the output of the next highest-producing well, which pumps 1,250 gallons per minute.

Our Well-14 effectively achieves a 4-log removal of contaminants by using chlorine, meeting both the water production requirements and the necessary chlorine contact time (CT) for disinfection. With 1450 linear feet of 18-inch pipe installed and a chlorine residual of 1.0 mg/L, there is ample redundancy in place to accommodate variations in chlorine levels and flow rates while still ensuring a 4-log removal of contaminants. 

FAQ - What is 4-log treatment? 

4-log treatment refers to a water purification process (inactivation, removal, or inactivation and removal) that removes harmful microorganisms to a very high degree. Specifically, it means that the treatment is effective in eliminating 99.99% of bacteria, viruses, and other pathogens from the water, making it safe for consumption.