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BACKGROUND In early 2018, the City performed the bi-annual cleaning and maintenance of all water reservoir tanks within the water distribution system. This effort included having a consultant scuba dive the tanks to perform inspections of the interior corrosion prevention coating systems. The inspections revealed the interior corrosion coating systems in the upper Ruby Hills tank, Moller Ranch tank and Laurel Creek tank need to be replaced due to significant and widespread corrosion of the interior metal tank walls. In addition, it was identified that the access hatch, ladders, cathodic protection and some of the vents of the three tanks also need to replaced. The condition of the upper Ruby Hills tank was expected. The condition discovered in the Moller Ranch tank and Laurel Creek tank was not expected. The upper Ruby Hills tank serves a large portion of the Ruby Hills development. Taking the tank out of service to perform maintenance has significant impacts on the water supply to the area residents. As staff was anticipating work on the upper Ruby Hills tank, Quincy Engineering, one of the City's on-call general civil engineering consultants, was issued a task authorization in April 2018 to study how water could be supplied to the Ruby Hills area while the tank is out-of-service. If the study determined a feasible method of taking the tank out of service, the intention was to expand that task authorization to develop plans and specifications to repair the existing tank. If the study was unsuccessful, the intent was to expand the task authorization to design a redundant tank for the upper Ruby Hills pressure zone. The study revealed that by-pass pumping could be used to supply water, but would only be effective during the winter months when demand is low. However, with the addition of the Moller Ranch tank and Laurel Creek tank, and the newly identified cathodic protection requirments for all three tanks, the project scope increased above the intended use of the on-call contract. Staff is now proposing to issue a separate contract for the proposed design work, which is the subject of this staff report. The Moller Ranch tank and Laurel Creek tank can be taken out of service with no by- pass pumping required, provided the work is accomplished during the winter months when water demand is low. DISCUSSION Quincy Engineering has the qualifications and experience necessary to design the proposed water tank rehabilitation project. They also have the experience to design the needed by-pass pump at the upper Ruby Hills tank. They were selected through the Request for Qualifications process as one of the City's on-call civil engineering consultant firms. Based on their knowledge and availability to perform on this project, it is recommended that the City enter into the attached contract with Quincy Engineering to complete the design and create a biddable set of plans and specfications. Schedule The proposed schedule for this project is as follows: Page 2 of 3