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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
This article describes rooftop water tanks and cisterns, where they are used, how they work, and the use of booster pumps to improve water pressure in buildings with rooftop water storage tanks. We also discuss using a booster pump to improve building water pressure in buildings with weak municipal water pressure or a weak rooftop
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Rooftop water storage tanks In some areas, Mexico, for example in our photo (above-left), rooftop water reservoirs are supplied intermittently with water from a water main in the street. The rooftop water storage tanks in this photograph from San Miguel de Allende in Guanajuato are being used both to accumulate a water reservoir so that water is always available to the building, and to supply water at a useful pressure.
Our second photograph of a large rooftop water storage tank was taken in Manhattan. Rooftop storage tanks atop tall buildings have been in use for hundreds of years - this one was constructed of wood with iron bindings and is used to provide good water pressure to fixtures in the multi-story building it serves.
See details at CISTERNS.
Reader Herman Voegel has pointed out that an up-and-coming area of storage containers includes spun-plastic tanks.
The plastic water tank in our photo (left) is used on ground level or on rooftops.
see PLASTIC CONTAINERS, TANKS, TYPES for details about using plastic tanks or containers for water storage.
General HDPE containers come in all shapes and sizes and are quite rugged and relatively cheap compared to using typical 12-gauge steel home heating oil tanks.
The ruggedness of HDPE plastic containers comes from their material density which is typically at a minimum specific-gravity of 1.7, and for heavy-duty at 1.9.
These tanks may be used for storing certain liquids besides water. But home heating oil has not yet been approved for storage in HDPE tanks, basically for two reasons:
However, fixes have been put in place to properly address these problems. UV-light is checked by using special color additives that prevent their light from penetrating and degrading the plastic walls. Permeation or seepage of oil through container walls is checked by coating them with fiberglass.
Unfortunately, even with these fixes, HDPE plastics for heating oil storage have yet to be universally approved and accepted.
Readers should also see PLASTIC CONTAINERS, TANKS, TYPES where we describe health and other concerns involving plastic tanks and other containers used for water storage.
Attic Water Storage Tanks or Attic Cisterns
Water storage may not be on the rooftop nor in the attic. Cisterns or other water storage containers are often located in the basement or courtyard of buildings where they collect rainwater for future use. In the U.S. cisterns were often located in the basement of a (pre-1900) home. See details at CISTERNS.
On low buildings or where the water tank is not high above the point of use some systems install a water pressure booster pump and tank. A water pump (WATER PUMPS, TANKS, DIAGNOSTICS) and probably a water pressure tank (WATER TANK BLADDERS & CAPTIVE AIR) will certainly be needed for ground-level or below-ground-level water storage cisterns.
Readers of this document should also see Water pump and pressure tank repair diagnosis & cost an specific case which offers an example of diagnosis of loss of water pressure, loss of water, and analyzes the actual repair cost and see Wells, Cisterns, & Springs for a discussion of types of drinking water sources and what goes wrong with water supplies.
If you're looking for information on types of septic tanks see our Septic System Design which includes articles about various types of septic tanks, steel, concrete, plastic, etc. The illustration at page top is courtesy of Carson Dunlop, Inc. in Toronto.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.