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:
| Cost of machine | $1,500.00 | ||
| Fixed charges. | |||
| Depreciation of 10% on (wagon & tank) | $100.00 | ||
| Depreciation of 25% on engine | 125.00 | ||
| Interest at 4½% | 67.50 | ||
| $292.50 | |||
| Maintenance | |||
| Painting (each season) | 20.00 | ||
| Hose and coupling, each season | 15.00 | 35.00 | $327.50 |
| 150 days operation—cost per day | $2.18 | ||
In recommending the flushing process the Milwaukee Bureau says that sprinkling will be greatly reduced, the slippery surface of thoroughfares due to this valueless method will no longer exist, and that a cleaner and more sanitary condition will be the result.
The experience of Scranton, Pa., with flushers is that in going over the streets but once satisfactory results are not obtained. The director of public works says that this has also been found in other cities he has visited where flushers are used. He has concluded that the only practical and efficient way to clean streets is by the use of automobile flushers, one to about one and a half minutes ahead of the other, the first flusher dampening the horse droppings and other material that may stick to the pavement, thus loosening them, and the second flusher sweeping them into the gutter.
Birmingham, Alabama, reports that its experience has been that a great saving and better results are obtained by substituting street flushers for sprinklers and brooms.
Some cities are having success with street railway flushers, among them Cleveland, Scranton, Columbus and New Bedford, Mass. Cleveland furnishes and maintains the flusher cars, pays the cost of operating them, including the wages of employees and the cost of power, but contributes nothing toward fixed charges or for track maintenance or renewal.
Commissioner John T. Fetherston, of New York City, reports that the Mack truck flushing machines which the city put into use during the summer of 1917 are capable, according to preliminary investigation, of cleaning from 100,000 to 120,000 square yards of street per machine per eight hour shift, and that they will do the work with the use of approximately 400 gallons of water per thousand square yards.