History of the Water Supply of the World / arranged in a comprehensive form from eminent authorities, containing a description of the various methods of water supply, pollution and purification of waters, and sanitary effects, with analyses of potable waters, also geology and water strata of Hamilton county, Ohio, statistics of the Ohio river, proposed water supply of Cincinnati.

by Thomas J. Bell

PUMPING SYSTEM.

The divisions of power are:

Wind Power. Water Power. Steam Power.

And the methods of supply by:

Reservoir. Stand Pipe. Direct or Holly Plan.

The value of a pumping system recommends itself on the point of economy in construction, for the outlay is in proportion to the existing necessities, which can be increased as the demands require. The original water consumers are not, therefore, taxed so heavily for future exigencies of gravity works. This idea can be better illustrated by the comparative cost of construction and maintenance of gravitation and pumping works:

	BALTIMORE	CHICAGO
	GRAVITATION.	PUMPING.
Available capacity for daily supply	200 millions	120 millions
Largest daily consumption in 1880	—	73 “
Total valuation of works	10 “	8.8 “
Bonded indebtedness	9 “	3.9 “
Annual interest	440 thousands	283 thousands
Annual current expenses	87.5 “	206 “
Annual maintenance, including interest at 5 per cent on total valuation of works.	587.5 “	646 “

	BOSTON	CINCINNATI
	GRAVITATION.	PUMPING.
Available capacity for daily supply	86 millions	36 millions
Largest daily consumption in 1880	28 “	38 “
Total valuation of works	18 “	7 “
Bonded indebtedness	12 “	1.6 “
Annual interest	619 thousands	108 thousands
Annual current expenses	211 “	200 “
Annual maintenance, including interest at 5 per cent on total valuation of works.	1,111 “	50 “

The reservoir system is the most preferable of the three methods, when natural elevation can be secured, for the pumping service is distinct from the distribution; and, where reservoirs of large capacities are obtainable, a closer margin for reserve pumping power can be adopted, besides a storage reservoir provides for contingencies that may arise, and allow cessation of pumping during the turbidity of water source, caused by sudden freshets.

The stand-pipe is adopted where the elevated grounds are not sufficient for reservoir purposes, to give a desirable water pressure; or where reservoirs may not be desired, but to secure the head and provide for a constant and reliable action of the pump that is not obtained by a direct system.