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Page 1 Repr in ted wi th permission from the October - December - 2005 issue of Plumbing Standards M agazine

High-rise buildings decorate the landscape of our ma-jor cities across our great nation. Not only are they a chal-lenge to build architecturally, but there are also many otherchallenging factors that go into each ones design, such aspumping water. Few people ever think about how the watergets to the top floors of these buildings for everyday livingpurposes such as drinking, bathing and mechanical uses

such as cooling towers and supplying HVAC equipment. Asyou read, you will understand that each high-rise buildingsplumbing design is just as important as any other aspect ofconstruction. No matter how big and beautiful the build-ing, it is not habitable without water.

The Early Days

As far back as high-rise buildings existed, ways to de-liver water to every floor was a necessity. The most commonsystem used in the late 1800s and early 1900s consisted ofa roof tank combined with constant speed pumps thatoperated by a level switch in the tank. When the level in thetank would approach a predetermined height, the pumps

would eitherturn on topump more wa-ter to the tankor turn off be-cause the tankwas full.

The rooftank system re-quired heatingthe water dur-ing the winter

to prevent freez-ing and duringthe summermonths the wa-ter was hot.One inherentproblem withthe tank systemwas the vaca-tion/ resort-likeatmosphere it

How PHow PHow PHow PHow Potable Wotable Wotable Wotable Wotable Water Risesater Risesater Risesater Risesater Rises

to the Tto the Tto the Tto the Tto the Top of Skyscrapersop of Skyscrapersop of Skyscrapersop of Skyscrapersop of Skyscrapers

By Mark Brickey, Paul Larson, P.E. & Joseph Sanchez of M etropolitan Industries(Information compiled by Gunnar Collins, IPP, FASSE, Collins Backflow Specialists, Inc.)

offered pigeons, which lead to unsanitary conditions. Onmany of the older buildings in major cities, you can stillsee some of these tanks on the rooftops although theymay not be in service.

In the 1950s, pneumatic pressure tank systems replacedmany roof tank systems. These systems put the pneumatictank inside the building, eliminating the pigeon problem.

The pumping equipment pumped water to the pneumatictank pressurized by an air compressor that supplied water tothe floors. The systems, for the most part, worked well ifproperly maintained, but required large areas for equipmentinstallation andwere expensiveto install. In ad-dition, thesesystems were bigconsumers ofenergy given theyran at a constantspeed, despite

low demand pe-riods where wa-ter is hardlyused.

The Present

Today, wa-ter pressure sys-tems, or boostersystems, havecome a long waysince the early

Typical Commercial Building

w ith Pneumatic Tank System

PNEUMATIC

TANK

WATER DISTRIBUTION

SYSTEM

PUMP SYSTEM

CITY WATER

MAIN

Typical Pneumatic Tank Pump System

WATER

TRAP

MOTOR

START

ELECTRODE

STOP

ELECTRODE

CHECK VALVE

AIR COMPRESSOR

PRESSURE SWITCH

RELIEF VALVE

PRESSURE TANK

PUMP SUCTION

Typical Commercial Buildingw ith Roof Top Tank

WATER TANK

WATER DISTRIBUTION

SYSTEM

PUMP

SYSTEM

ITY WATER

MAIN

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