Distribution systems Designed to adequately satisfy water requirements for combination of: Domestic use Commercial Use Industrial Use Fire-fighting Have to consider: Flow Pressure Quality
Distribution System Classifications Branching System Grid System Combination system
System Type Advantages Branching System Grid System Combination System
System Requirements Commercial Pressure greater than 60 psig typically required Residential Pressure of 40 to 50 psig Tower Buildings Intermediate booster pumps with storage tank on top
Select pipe sizes to avoid hig velocities Velocities typically between 3 to 5 fps at peak flows * Inch pipes recommended in areas were fire-fighting demands are expected. 6 inch pipe may be used if a grid type system is used and length between connections is lesss than 600 feet.
Distribution Reservoirs and Service Storage Storage reservoirs are used to meet fluctuating demands, to accommodate fire-fighting and emergency requirements, and equalize operating pressures. Types of storage reservoirs: Surface reservoirs Standpipes Elevated storage tanks Locate reservoirs and storage to maximize benefits. Usually near the center of use. High enough to supply necessary pressure in the system
Modes of Operation Demand light – pumping station will met needs in system and supply water to storage tank. Demands high – both the tank and the pumping station will be needed to supply the flow