Part 3

The unit work must be established and the responsibility of each employee fixed in order to secure an economical administration of street cleaning. This principle is illustrated by the so-called “block system.” By this, each man is allotted to a definite area of pavement to clean, which varies in extent depending upon local conditions as to traffic, physical condition of pavement, location of street, proximity to public buildings, population, paving, alleys, street cars, right of way and frontage of streets.

It is the practise of up-to-date cities to prepare schedules showing the character of pavement, area of pavement, number of cleanings or patrols per week, and the standard of work required of each street cleaner. Changes in these schedules are necessary from time to time on account of climatic conditions, street repair and other necessities. The Chicago Civil Service Commission says that to obtain definite standards of schedules for cleaning streets and alleys and the need of repairing such streets, the routing of teams and vehicles, collecting of city waste, the amount and character and physical condition of all pavements must be obtained.

Pavements are usually classified according to physical character for the purpose of determining the amount and character of cleaning as follows:

* * * * *

Improved—Permanent (a) Smooth pavements, including asphalt, creosote block and bitulithic. (b) Rough pavements, including brick, granite, cobble and rubble and other pavements which require that dirt be picked from interstices.

Improved—Not permanent. All macadam pavements and country roads.

Unimproved pavements. All streets that have not been paved.

The oiling of macadam within the past few years has had an excellent effect on this kind of pavement and has given it the solidity and usefulness almost approaching improved permanent pavements. On macadam surface streets, periodical removal of rough material with hoes, brooms and shovels from street surface and gutters and sprinkling in dry weather with water or oil is about the best that can be done. An analysis in Chicago of the standard of work which one man can perform on an oiled macadam street, indicates that the rate of cleaning one and three-quarters miles of oiled macadam of average width in an eight hour day can be reasonably expected of any man.

Much waste is caused by lack of system in laying out the work and improperly directing the street cleaning gangs and teams. The attached tables give the systems now being used in fifty American municipalities. A study of these will show that some very definite ideas have been developed by street cleaning officials in this country. For example, most cities prefer having patrolmen work singly instead of in gangs.

In making assignments attention should be given to the smallest details, such as correct reports from foremen as to the number of streets swept and loads carted away, and the correct number of sweepers in each street. In many cities three are sent through a street when two would do. Dirt wagons should not be started immediately behind sweeping gangs as it usually takes thirty minutes to an hour before a gang can sweep up enough dirt for a full load. Dirt teams should not start for at least one hour after the sweeper begins. Gangs should have allotted to them enough work to keep them busy until quitting time so that they do not have to kill time. Laxity in any part of the system eats up the department appropriation.

Spring Cleaning

The spring cleaning system usually calls for the piling up and removal of the heavy dirt which is washed from the center of the street and which accumulates in the gutters during the winter season. The experience of cities with such work indicates that the assignment of one man to a definite length of street, or the assignment of a small gang of not exceeding three men, to definite lengths of streets is more effective and economical.

The Chicago Commission says that where a gang of three men is assigned to the work, team work is developed by the use of one man in removing the dirt from the roadway and one man each from the gutters. In the granite and brick pavements considerably more brooming is necessary on the roadway. Granite, brick and cedar block pavements require that the dirt be scraped from the center of the street to the gutter before piling in the gutters can be commenced. The center cleaning rates per man in Chicago are given as follows:

┌─────────────────────┬─────────────────────┬─────────────────────┐ │ │ Car Track │ Outside Car Track │ │ │ Sq. Yds. per Day │ Sq. Yds. per Day │ ├─────────────────────┼─────────────────────┼─────────────────────┤ │Good Asphalt │ 16,500│ 18,500│ │Fair Asphalt │ 12,900│ 14,800│ │Poor Asphalt │ 9,200│ 11,100│ │Good Brick │ 4,400│ 5,500│ │Fair Brick │ 3,540│ 3,700│ │Poor Brick │ 1,850│ 2,960│ │Good Granite │ 4,400│ 5,550│ │Fair Granite │ 3,340│ 3,700│ │Poor Granite │ 1,850│ 2,220│ │Cobblestone │ 1,470│ │ └─────────────────────┴─────────────────────┴─────────────────────┘

The single gutter rates in miles per day per man are given as follows:

┌──────────────┬────────────────┬────────────────┬────────────────┐ │Times Cleaned │ │ │ Poor Brick and │ │ per Week │ Asphalt │ Good Brick │ Granite of All │ │ │ │ │ Kinds │ ├──────────────┼────────────────┼────────────────┼────────────────┤ │ 2 │ 1.8 miles │ 1.4 miles │ 1.4 miles │ │ 3 │ 1.4 miles │ 1.1 miles │ 0.7 miles │ │ 6 │ 0.7 miles │ 0.5 miles │ 0.3 miles │ │ 9 │ │ 0.3 miles │ 0.2 miles │ │ 12 │ │ 0.2 miles │ 0.2 miles │ └──────────────┴────────────────┴────────────────┴────────────────┘

Chicago has found that the unit cost of spring cleaning of macadam and cedar block streets of different physical condition is as follows:

┌─────────────────────┬─────────────────────┬─────────────────────┐ │ First Class │Fair Condition, Cost │Poor Condition, Cost │ │ Condition, Cost for │for Cleaning 100 Lin.│for Cleaning 100 Lin.│ │Cleaning 100 Lin. Ft.│ Ft. │ Ft. │ ├─────────────────────┼─────────────────────┼─────────────────────┤ │ Traffic │ Traffic │ Traffic │ │ Heavy Light │ Heavy Light │ Heavy Light │ ├─────────────────────┼─────────────────────┼─────────────────────┤ │ $1.18 $.90 │ $1.97 $1.46 │ $2.25 $1.89 │ └─────────────────────┴─────────────────────┴─────────────────────┘

Street Sprinkling

Although many cities sprinkle their streets for dust laying only, it is agreed by all experts and the heads of most street cleaning departments that the use of sprinkling carts for this purpose is of no value, _i. e._ it is a temporary makeshift and the result is nil. Sprinkling alone does not clean pavements, but only converts temporarily the fine dust into mud, which is a nuisance. It is quite generally agreed, too, that sprinkling is responsible for much repair work on pavements.

The number of times a street is sprinkled daily depends upon weather conditions, nature of pavement and location, and rarely exceeds four trips. Where flushing and squeegeeing are done sprinkling is eliminated entirely.

In Providence, Rhode Island, bituminous pavements are not sprinkled by water. They are kept clean by patrol system and reasonably free from dust. It is the belief of officials of that city that the use of water has an injurious effect on the pavement.

George D. Warren, of Boston, an expert on paving, says that street sprinkling as it is generally practised is worse than a useless expense. He points to the fact that there has been no sprinkling in Providence in seven years on all kinds of pavement, except that water bound pavement is occasionally sprinkled with oil or oil emulsion. If bituminous pavement surfaces are dry and clean the oil which drips from automobiles is quickly spread by auto tires to an extremely thin sheet, which not only preserves the pavement, but the slight amount of oil takes up the fine dust and materially helps to prevent the surface from even becoming dusty.

Mr. Warren believes that while some forms of pavement are doubtless more affected by water and mud than others, sprinkling injuriously affects all classes of pavement. Continuing he says: “I believe that repairs required to all classes of pavement are more generally the result of wetting down the dirt, leaving the surface in a more or less muddy condition than by traffic, or rather what would be traffic under dry cleaning conditions. A city or street in or on which sprinkling or other methods of continual wetting of pavement surface has not been practised is almost usually one where the pavements are the best of their kind. Washington has the enviable reputation of having the most durable pavement of all kinds. For many years the system of cleaning there has been hand patrol without sprinkling, except a very light sprinkling, just enough to lay the dust, not to convert it into mud—immediately in advance of night sweeping.

“Fifth Avenue, New York, is always dry except during rains, and we find one of the most durable asphalt pavements in the world. The pavement is always clean and never dusty.

“Asphalt pavement on Alexander Street, Rochester, New York, laid in 1885, is still in existence and has a record for low cost of repairs, and has until quite recently been free from street sprinkling. It is now rapidly deteriorating.

“Rutger Street, in Utica, New York, laid in 1886, has been through a similar experience of no sprinkling. Michigan Boulevard in Chicago, from Jackson Boulevard to 10th Street, was paved partly with creosoted wood block and partly with asphalt. It was always in a dry condition and carried very heavy traffic for ten years and was in a good condition until about four years ago when it was removed on account of widening the street. The bituminous pavement on Michigan Boulevard is always clean and never cleaned or sprinkled other than by patrol cleaning, except as to narrow strips about four feet wide which are sprinkled and hand broomed at night to remove the slight dust which collects near the curb.”

The Bureau of Municipal Research of Milwaukee reports that in that city 298 miles of street are sprinkled at a cost of $60,310.05. Of this amount $55,104.77 is assessable.

The balance is the city’s portion for public property and street and alley sections which is charged to the general city fund. The city used 275,498,112 gallons of water, costing $28,416.65 including $8,800 for hydrant rental. The average rate of assessment per foot front is about .017¢. In some cities where water is unavailable outside of city limits, or available only for a short time, oil has been used to meet the demands for dust prevention. What seems to be the best is some non- volatile oil that will quickly penetrate the wearing surface of the road incorporating itself with the fine particles so that it forms a dense, smooth, waterproof coating, or else renders the surface dressing so heavy that wind will not hold it in suspension in the air. In addition to this its non-volatile character gives it lasting qualities.

The Milwaukee Bureau of Municipal Research believes that “The service at its best is of no value as it does not clean but only allays dust on the street where in its wet condition it requires a further process of cleaning by the squeegee or flusher and White Wings. If the city had a sufficient amount of modern equipment to clean streets more frequently, the valueless method of sprinkling could be eliminated and an enormous expense saved.”

In some cities street railway companies are required to sprinkle between their tracks and for certain distances on either side of the track. The legal question has several times arisen, whether a Municipal corporation has authority to enact an ordinance to compel railway companies to sprinkle in this way and also whether the particular ordinance in question is reasonable, or so unreasonable as to be void. Generally speaking it has been decided that such an ordinance must be specific, not burdensome, and confined to the company’s tracks, though in one case in Massachusetts, under the statutory powers conferred upon municipal authority, an ordinance requiring sprinkling from curb to curb was sustained. Courts have held that an ordinance providing that “each and every Company or Corporation operating street car lines within the limits of the city of ——— shall water their tracks so as to effectually keep the dust on the same laid,” and provides a penalty for its violation, is neither indefinite nor wanting in uniformity.

The question of sprinkling streets before sweeping has been discussed repeatedly. Following are the methods used in some cities:

_New York._—Sprinkling before machines. No sprinkling before hand sweeping.

_Chicago._—Sprinkling before sweeping. The Chicago Code of 1911 requires that street car companies shall keep well sprinkled with water in a manner satisfactory to the Commissioner of Public Works, all streets on which they maintain and operate their tracks. They are required to sprinkle such streets twice each day. By another section such street car companies shall clean such portions of streets as lie between the two outermost rails of such tracks and also every additional service as may be prescribed in any railway ordinance relating to or affecting any street.

_Philadelphia._—The proposals and specifications for the cleaning of streets, roads, alleys, inlets and markets for 1915, contained the following provision: In addition to the cleaning by blockmen required under these specifications, all streets must be periodically cleaned by machines, the number of weekly cleanings being given in the classification of streets, the remaining machine work shall be done with machine brooms immediately preceded by sprinklers.

_St. Louis._—Sprinkling before sweeping is very rarely done, except in the case of certain large sweeping machines used by the city.

_Baltimore._—Sprinkles before sweeping.

_Pittsburgh._—Principal thoroughfares including all streets in business district cleaned by machine sweepers. Water cart precedes sweeping machine. The cart must never be more than one block ahead of the sweeper.

_Washington._—Superintendent of street cleaning gives his opinion that much more effective sweeping can be done without sprinkling and in hand patrol work where dirt is not allowed to collect in any considerable quantity is not necessary. In machine sweeping, however, he finds it necessary to sprinkle with a small amount of water. In cold weather sprinkling is omitted; but at such times many complaints are received on account of dust.

_Minneapolis._—In general the orders of the street district commissioners are to sprinkle the streets before sweeping.

Street Cleaning Methods

Four methods are used in American cities for street cleaning, hand sweeping, machine sweeping, flushing by machine and hose and squeegeeing.

All experts advocate the sweeping of streets by hand, commonly called the patrol system. The implements used in patrol cleaning are broom, pan scraper, squeegees, can carrier and cans. The broom is usually one which has a 4 × 18 inch block, filled with split bamboo, rattan, hickory, steel wire or black African bass. The block is usually fitted with a steel scraper. The pan scraper is constructed like a dust pan, turned up sides and back. It is about 36 inches wide by 15 inches deep. The squeegee is a board about 36 inches wide fitted with a rubber strip which extends below the lower edge of the board. Brooms, pan scrapers and squeegees have handles about 66 inches long. The cans are made to hold about three cubic feet of dirt and taper 19 inches in diameter at the top to 17 inches at the bottom. The can carrier has two large wheels and two small, and a platform upon which the can or cans rest.

A new carrier has been devised which carries two cans and is so balanced that the two cans are more easily manipulated than the one. Some cities are now substituting canvas bags for cans.

Whinery says that when street surfaces are of such character as to admit it, hand sweeping is the most effective method.

J. W. Paxton says that hand cleaning work is capable of better distribution than any other method, because more attention can be given to dirtier areas by increasing the number of men who only clean the portions of the street which are dirty and work on those portions until they are clean. There is a fine scum which is not apparent when the pavements are dry but rises up in a thin sheet of mud when moist, making the pavements very slippery. This and fine dust cannot be removed by hand cleaners, but by washing about twice a week in addition to hand cleaning, these troubles can be eliminated.

Very believes that this method of cleaning is fairly effective but is a dust raiser and the ability of the man to cover areas is very limited, especially since the automobile has come into such general use, as it interferes with the sweeper and his work. He says that there are hand machine brooms built on the principle of the carpet sweeper which are not dust raisers and which as a matter of fact do much more effective work. The pan scraper is only valuable to remove manure and mud and coarse litter, and its use should be limited to the time necessary for such work, and the broom used for dust removal.

The area a sweeper can clean depends upon the existence of local conditions. A test was made in New York City for one week and it was found that the area one sweeper was able to clean in a day of eight hours varied from 2,212 square yards to 16,075 square yards, with an average over the whole city of 5,745 square yards. The efficiency division of the Civil Service Commission of Chicago reports: “From an analysis of the findings of the time and motion studies of street cleaners the following table has been deduced, upon which are based the relative difficulty of cleaning different pavements under varying conditions and the standard and equivalent areas to be cleaned by one man in one eight-hour day.”

┌────────────────┬────────────┬────────────┐ │ Pavement │ Condition │Square Yards│ ├────────────────┼────────────┼────────────┤ │Asphalt │Good │ 21,500 │ │Asphalt │Fair │ 19,300 │ │Asphalt │Bad │ 17,200 │ │Creosote Blocks │Good │ 21,500 │ │Brick │Good │ 16,000 │ │Brick │Fair │ 14,400 │ │Brick │Poor │ 12,800 │ │Granite │Good │ 13,400 │ │Granite │Fair │ 12,100 │ │Granite │Poor │ 10,700 │ └────────────────┴────────────┴────────────┘

In Philadelphia, which cleans its streets by contract, block men are assigned to sections designated by the chief. The area to be covered depends upon the character and amount of traffic. The duties of block men consist in patrolling the areas, gathering all papers and refuse and sweeping dirt as fast as it accumulates, and putting it into dust proof bags ready for loading into special wagons and hauling to a dumping station. The equipment used in hand patrol work consists of hand machines, bag carrier, burlap sacks, push brooms, hand scrapers, special cans and shovels. The dirt collected is placed in sacks and left at convenient points to be collected by special wagons and taken to the dump in sacks, these being returned by the drivers. Sacks are used in preference to cans because of the weight, bulk and noisiness of the latter.

Machine Sweeping

Machine sweeping and cleaning is almost universally condemned, although this method is used in many cities. The machine broom is preceded by a sprinkling cart to loosen the filth and in a measure to prevent the dust rising. This is seldom effected. A broom is found to cover about 40,000 square yards per eight hours. The material is swept into windrows at the side and finally delivered to a windrow in the gutter, where it is picked up. The efficiency of the rotary broom system is considerably reduced because the sweepers meet continual obstructions in busy streets and when operating over paved streets the brooms remove the coarser fragments of dirt only and leave the finer particles on the pavement.

Where the rotary broom is preceded by a street sprinkler, the dust forms into mud and clings to the surface of the pavement, and where the pavement is rough the mud is forced into the joints between paving blocks. As the street becomes dry, the dirt pulverizes and appears again as a dust nuisance. In all but one instance machine sweepers have been dispensed with in Chicago. South Water Street, the heavy wholesale fruit district of the city, is badly congested during the day, which makes it impossible effectively to clean this district by the “block” system. This street becomes very dirty during the day and is covered with a thick layer of dirt and débris at night. In this instance, the broom machines appear to be effective and give fairly good results in the cleaning of this coarse material.

The Chicago Commission believes that the mixing of calcium chloride with the water which is sprinkled in the different sections of the city would greatly add to the effectiveness of street cleaning and eliminating the perils of dust.

According to Very horse drawn brooms of the rotary style are not as effective as the hand broom.

Whinery says, “Sweeping by power sweepers at intervals of one or more days, while less expensive is far less effective and satisfactory than hand sweeping, though if properly done and supplemented by sprinkling with water or oil at intervals sufficiently near together to prevent dust flying it serves a good purpose.”

J. W. Paxton is of the opinion that the machine broom raises so much dust that heavy sprinkling is required. The fine dust mixed with water produces mud which is smeared on the street by the broom and when this becomes dry it turns to dust again. The broom sweeps only the coarser particles and many of these are thrown over the broom by centrifugal force to the pavement again.

In Philadelphia, machine broom cleaning is done in batteries of two or three, preceded by sprinklers, the number of brooms in each battery depending upon the width and character of the streets to be cleaned. The average gang consists of two machine brooms and one sprinkler, and four to seven broomers and a sufficient supply of wagons to remove the refuse, the number depending upon the haul to the dump and season of year, together with amount and character of traffic.