“Water should also be applied with force enough to carry the refuse to gutter where it should be properly collected with broom and shovel and removed. In Philadelphia flushing machines are used only on poorly paved streets and block pavement. High pressure flushing machines are usually operated similarly.”
Very reports that objection is made to flushing because materials are washed into sewers. The same objection, he says, might be made to hand sweeping, as many sweepers are like housemaids and sweep the dust into the catch basins to make work easy. The material need not reach the sewers if the operator knows his business. Many fear that the action of water when used in flushing will wear away the pavement surface or the joint materials. His answer is that it should, if such a class of pavement or of jointing is allowed to be laid, to expose the paving contractor.
The Chicago Civil Service Commission says that personal inquiry and analysis of reports from cities using flushing machines seem to indicate that the use of flushing machines on rough and smooth pavement and the use of squeegees on smoother permanent pavements have given more effective cleaning than the ordinary block or gang cleaning where it is practicable to make the substitution.
The Milwaukee Bureau of Municipal Research, in its investigation of street cleaning in that city, says the contention of some is that flushing is detrimental to pavement as it removes grout, but such has not been proven in Milwaukee. The one fact that remains uncontradicted is that they clean the streets of every particle of débris and leave the thoroughfares in a sanitary condition; a matter of most vital importance.
In Milwaukee night work is confined to two territories comprising the heavy traffic and commercial territories and each alternating night the streets are flushed. This requires the use of four machines and they operate in a staggered double formation, cleaning the entire area without a return movement. When intersecting streets are encountered, the two rear machines perform the work and then return to the original function. A great deal more territory is thus covered than if machines were paired and each allotted a given area. Day work is performed in like manner except that the remaining four machines are assigned to outlying districts and confined thereto. The following is the cost of operating machine flushers as computed by the Bureau: