Greeley and Hansen, A TYLin Company, developed a water system master plan to address near-term needs and long-term planning of its water system.
Saginaw receives its raw water supply from Lake Huron through 65 miles of pipe terminating at their 52 MGD conventional water filtration plant located in the center of the City. Treated water from the plant is pumped to City water users and to 19 wholesale customers. In addition to its 52 MGD treatment plant, system facilities include two 90 million gallon raw water reservoirs, one 30 million gallons raw water reservoir, two raw water pumping stations, approximately 27 million gallons of finished water storage, six booster pumping stations, and over 400 miles of water mains ranging in size up to 48 inches in diameter.
Based on the diversity of needs of the Saginaw Water System, Greeley and Hansen utilized a holistic approach in addressing the required planning. Several critical issues were identified early in the planning and were addressed and then resolved. One such issue included the conversion from liquid chlorine disinfection to disinfection using sodium hypochlorite for added safety and security at the treatment plant. This project was completed and placed in successful operation during the progress of the master planning.
Initial planning studies of treatment plant alternatives indicated that rehabilitation and continued use of the existing water filtration plant, placed in initial operation in 1929, to be the most economical project for meeting estimated water demands through the year 2030. To meet increased demands beyond year 2030, expansion of the existing plant capacity or construction of a second water treatment plant to serve along with the rehabilitated existing plant was determined to be required. Treatment process studies, based on existing plant performance and an assessment of current and future treatment regulations, indicated no need to change from conventional filtration in the plant renovations or future plant improvements.
Master planning for the finished water distribution system was also conducted. Assessment of distribution system storage and pumping capacity needs were completed as well as computer modeling to determine needs for distribution system water mains. Project tasks included computer modeling and engineering analysis to finalize water main needs and appropriate storage and booster pumping station locations for meeting future water demands of system users. The modeling efforts included the selection of modeling software based on planning needs and other client-desired modeling features; preparation of the system model based on system water main, pumping station, and storage facility data provided by City staff; calibration of the model based on hydrant flow testing planned and conducted as a part of these studies; and use of the model to predict system performance and needs under current and future water demand conditions for several system development scenarios considered. The modeling results and analysis indicated the need for significant new water mains in future years to better meet future water demands.
A capital improvements implementation plan was prepared to assist the City in moving forward with recommended improvements for both its treatment plant facilities and its distribution system. The plan organizes recommended improvements into three implementation categories based on need: priority improvements; improvements with current benefits that can be deferred and future improvements. Along with an overall timetable for the improvements, sets of trigger events are identified so the City can make informed decisions to move ahead or defer improvements based on system needs.
CIP development to prioritize capital projects for implementation
Near-term and long-term needs addressed
Upgrade of disinfection facilities at the water treatment plant
Modeling of the water distribution system