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Topic I.10. Service Reservoirs:Kinds, Structures and Volume

Main Functions of the Service Reservoirs: To insure the necessary head at the water distribution

network (reservoir elevation) To insure the balance between water inflow and outflow

(reservoir useful storage volume) To keep the fire water volume (if necessary)

Kinds of Service ReservoirsI. According to their location and technological function Crossover type Endmost type Intermediate type

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Kinds of Service Reservoirs

Crossover Type

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Kinds of Service Reservoirs

Endmost Type

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Kinds of Service Reservoirs

Intermediate Type

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Kinds of Service Reservoirs

II. According to their structure

Sunken type (dig into the earth)

Elevated (Tower) type

Standpipe (Column) type

III. According to their protection

Open

Covered

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Kinds and Structures of Service Reservoirs

Sunken Type Shapes(schemes)

1 - water inflow pipe2 - water outflow (feeding)

pipe

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Kinds and Structures of Service Reservoirs

Pipe Systems at the Sunken Type Service Reservoirsa - inflow pipe systemб - outflow (feeding) pipe systemb - overflow and drainage pipe system

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Kinds and Structures of Service Reservoirs

Sunken Type Structure (Plane)

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Kinds and Structures of Service Reservoirs

Sunken Type Structure (Longitudinal Section)

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Kinds and Structures of Service Reservoirs

Sunken Type Structure (Cross Section)

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Kinds and Structures of Service Reservoirs

Elevated (Tower) Type Standpipe (Column) Type

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Kinds and Structures of Service Reservoirs

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Service Reservoir Volume Sizing

V = Vr + Vf , m3

V - total reservoir volume, m3

Vr - regulation (useful) reservoir volume, m3

Vf - fire water reserve volume, m3

Vf = 3,6.Qf.Tf , m3

Qf - fire water flowrate, l/sTf - fire duration, h; Tf = 2 - 3 h

Determination of the Regulation Reservoir Volume

I. With known water inflow/outflow regimes

Vr = 1,2.(V1 + V2)I. With unknown water inflow/outflow regimes

Vr = (0,3 - 0,5).Qmax,d

Qmax,d - daily maximal water consumption, m3