Cleaning by Flushing
All authorities agree that whatever method for primary cleaning is adopted, it is important that the street surface be frequently washed by the use of hose, horse drawn flushers, flushing cars, or power squeegees. Reports from cities show that flushing is replacing machine sweeping and that the automobile flusher is becoming popular. The Chief of the Atlanta Sanitary Department favors doing away with sweeping machine and cleaning the streets entirely with flushing machines. He says that sweeping machines are out of date and that flushers are the ideal machines.
The squeegee is a vehicle having a tank and a revolving rubber roller, which washes the pavement as the vehicle moves along the street and the water from the tank is sprinkled in front of the roller. Hose flushing is used in cities having graded streets and sufficient water supply. Street flushers have pressure tanks which depend for their pressure either upon the pressure from the water mains or upon the pressure obtained from a pump operated by a gasoline engine. The latter plan gives the better results.
Whinery is of the opinion that on well paved streets the most efficient and satisfactory method so far devised with the apparatus now available is hand cleaning by the patrol system by day, followed with hose or flushing wagons or scrubbing squeegees during the night. While this is somewhat more expensive than plain machine sweeping he thinks that no other method yet devised will produce equally clean streets at a lower cost.
Gustave H. Hanna says: “The use of flushers has proven not only the cheapest but the most satisfactory method of street cleaning that our experience in Cleveland has been able to develop. Statistics of the department show an average cost of 15.3 cents per square of 10,000 square feet for flushing to which must be added practically 9 cents for pick-up work, a total of some 24 cents per square as against 42 cents for work with White Wings. The White Wings are too convenient and necessary an adjunct to be wholly displaced under any consideration. Down town streets must be swept continually during the day and the hand sweeper with his small cart can also work to advantage in gutters of residential streets collecting dirt that has either been flushed or blown to the curb; but so far as our experience goes, the lessening of cleaning cost by cheaper methods means simply the extension of the use of flushers at every practical point.
“There is an argument of sanitation in favor of flushing. Hand sweeping causes a certain amount of dust and mechanical sweeping usually causes still more. I am opposed to the use of simple sprinkling as a means of laying dust. Ammonia and other products leach out of damp manure and form a scum on the surface that is nearly impossible to remove, and makes pavement slippery and foul smelling.
“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:
| 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.