The City of North Chicago operates a conventional Lake Michigan water treatment facility. It has a rate capacity of 16 mgd with a typical utilization of 2.8 to 3.6 mgd. It services 16,813 residential and non-residential customers including a global pharmaceutical producer and several high volume institutional customers. It also has emergency interconnect with the Naval Station Great Lakes and Lake County Public Water systems.

On the morning of July 29, 2015 the lower levels of the City of North Chicago’s Water Treatment Facility was flooded when several gate valves malfunctioned due to becoming fouled with zebra mussels. The City of North Chicago worked together with Trotter and Associates and Dahme Mechanical Industries, Inc. to replace the inoperable valves on an emergency basis.

It was decided that the best course of action would be to replace the seized gate valves with AWWA butterfly valves (which would be less likely to become fouled by mussels in the future). It is important to note that the shutdown required for replacement had to be as short as possible in order to restore flow of cooling water to the major industrial user’s manufacturing process.

All the affected gate valves (originally put into service in 1991) were replaced (three 30” and four 20” gate valves). The emergency construction started immediately after the valves were delivered on January 26, 2016. The work was completed over two weekends minimizing the downtime to a matter of hours. The construction was completed and the plant brought back to full operation on February 8, 2016.

Upon completion of the emergency repair work to bring the plant back into full operation, attention was turned to paint and other finishes that may have been damaged by the flooding, or were in need of refinishing. With specification and bid documents prepared by Trotter and Associates a contract was awarded to BP&T Company to address the protective finishes around the plant.