AWWA IMTECH57876

The San Juan Water District (District) currently supplies domestic water to its customers through a system of water treatment, pumping and storage facilities. Increasing water demand within their P40 Pressure Zone during peak hour operating conditions has caused the need for additional water facilities. The proposed solution to augment the water supply to this pressure zone is to construct a ground level water storage reservoir located at an elevation sufficient to serve the pressure zone by gravity flow. The City of Roseville (City) has identified a service area adjacent to the P40 Pressure Zone as also needing a water storage facility. The organizations are proceeding with a joint 5 MG prestressed concrete water storage facility project. Storage spaces for each entity will be kept separate because of different water quality requirements of the District and the City. The City fluoridates their drinking water while the District does not. A draft feasibility study for the Joint Water Storage Facility was submitted in February 2001. The main issue associated with that initial study was the concern of the ability of the District and City to fill the storage facility during summertime operational conditions. In addition, the District has concerns about the effectiveness of the stored water at the remote site to meet the needs of the P40 Pressure Zone. The City has also expressed concerns on the operation of the facility with their ultimate Pressure Zone 2 (PZ2) pumping and distribution system. To address these concerns, West Yost & Associates (Consultant) was retained to develop and perform a rigorous modeling program to update the District and City simulation models, including collecting field data to calibrate and verify the accuracy of the model results. Using the updated models, the Consultant reevaluated the ability of the Joint Water Storage Facility to effectively serve the P40 and Zone 2 pressure zones. In addition, the Consultant identified other system improvements, to increase the level of service in each pressure zone resulting from use of this project. This paper outlines the use of the advanced modeling techniques in developing a comprehensive operational model, sites specifics on how the model was calibrated and summarizes results on how the use of advanced modeling techniques were imperative in developing an operational model that simulated the true behavior of water distribution system functions. Includes figures.