Page 321 - Fair, Geyer, and Okun's Water and wastewater engineering : water supply and wastewater removal

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8.6 Types of Distributing Reservoirs 281

Useful
storage

Useful
storage
Supporting
storage
Supporting
storage

Inlet and Inlet and Drain
Overflow outlet outlet
Drain
(a) (b)

Useful
storage

Municipal
offices, etc.

Original surface

Inlet and Drain
outlet
(c) (d)
Figure 8.7 Types of Service Reservoirs (a) Standpipe; (b) and (c) Elevated tanks; (d) Ground-
Level Service Reservoir

The useful capacity of standpipes and elevated tanks is confined to the volume of
water stored above the level of wanted distribution pressure. In elevated tanks, this level
generally coincides with the tank bottom; in standpipes, it may lie much higher. Steel tanks
are welded or riveted. Their structural design and erection have become a specialized ac-
tivity of certain tank manufacturers.
The function of elevated tanks and spheroidal tanks can be expressed to aesthetic ad-
vantage in their architecture without resorting to ornamentation (Figs. 8.9 and 8.10).
Standpipes are simple cylinders. A veneer or outer shell of concrete or masonry may make
them attractive. They may be designed as parts of multipurpose structures. The lower level
may serve for offices, warehouses, or other functions. At the top, sightseeing or restaurant
facilities may convert a potential eyesore into a center of attraction.