Municipal engineering and sanitation

Front matter

LIBRARY Brigham Young University

From

Oill No

Preface

This volume is intended for that large and rapidly growing class of persons who, either as officials or as citizens, are striving to improve municipal conditions. It is designed to be a review of the whole field of municipal engineering and sanitation, rather than an exhaustive study of one or a few branches of the subject. The most vital points, however, under each class of activities and interests have been dwelt upon, the underlying principles stated, and, in many instances, details from actual practice given.

While it is not to be expected that engineers and sanitarians will find in the book much relating to their specialties that is new to them, it is believed that the number and variety of subjects treated, and the comparative newness of some of the topics, will make the book helpful even to professional men.

A few standard treatises have been mentioned in the text or in footnotes. For an exhaustive bibliography, the reader should consult Mr. Robert

V vi

PREFACE

C. Brooks's Bibliography of Municipal Problems and City Conditions" (New York, 1901). This admirable work includes books and periodical literature, both American and European, and is brought down to the end of 1900.

It gives me pleasure to state that in preparing this book I have been greatly aided by my wife, Ella Babbit Baker, who wrote Chapters XIII., XIV., XXL, and XXIX. to XXXII., inclusive, and assisted in revising the whole volume.

M. N. B.

Upper Montclair, N.J.

November 7, 1901.

Introduction

CHAPTER PAGE

I. The City and its Needs 3

WAYS AND MEANS OF COMMUNICATION

II. Streets, Pavements, and Sidewalks . . . .11

III. Subways for Pipes and Wires 25

IV. The Elimination of Grade Crossings ... 29 V. Urban and Interurban Transportation • • • 33

VI. Bridges, Ferries, and Ice-boats .... 45

VII. Docks and Harbor Facilities 52

VIII. Telegraph, Telephone, and Messenger Service . 55

MUNICIPAL SUPPLIES

IX. Water and its Distribution 61

X. Water Purification 76

XI. Water Consumption and Waste Prevention . . 84

XII. Pure Ice . .90

XIII. Sanitary Protection of the Milk Supply ... 93

XIV. Markets and Slaughter-houses .... loi XV. Municipal Office Buildings 106

XVI. Light, Heat, and Power 1 10

COLLECTION AND DISPOSAL OF WASTES

XVII. Sewerage and Drainage 125

XVIII. Sewage Disposal 136

XIX. Street Cleaning, Sprinkling, and General Scavenging 151 XX. Disposal of Garbage and Other Refuse . . -157

XXI. Cemeteries and Crematories 167

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CONTENTS

PROTECTION OF LIFE, HEALTH, AND PROPERTY

CHAPTER PAGE

XXII. Fire Protection 175

XXIII. Building and Plumbing Regulations . . . 182 .

XXIV. Electrolysis of Underground Pipes . . .189 XXV. Smoke Abatement 192

XXVI. Suppression of Noises ..... 196

XXVII. Disinfecting Methods and Apparatus . . . 199

XXVIII. Prevention of Water Pollution .... 202

XXIX. Public Baths and Wash-houses .... 206

XXX. Public Lavatories and Water-closets . . . 214 XXXI. Municipal Dwelling and Lodging Houses . .217

XXXII. Municipal Parks, Playgrounds, and Gymnasiums 224

ADMINISTRATION, FINANCE, AND PUBLIC POLICY

XXXIII. City Charters 233

XXXIV. Municipal Experts and Specialists , . . 237 XXXV. The Departments of Public Works and Engineering 240

XXXVI. The Work of Boards of Health .... 248

XXXVII. Day-labor and the Contract System . . . 259

XXXVIII. Municipal Franchises and Contracts . . . 264

XXXIX. Municipal Ownership 275

XL. Municipal Expansion by Annexation and Consolidation 282

XLI. Municipal Cooperation a Substitute for Consolidation 290

XLII. Uniform Accounting and National Municipal

Statistics ....... 296

XLIII. Taxation, Assessments for Benefits, and Bonded

Indebtedness 303

INTRODUCTION

MUNICIPAL ENGINEERING AND SANITATION

CHAPTER I The City and its Needs

Great as was the increase in urban population during the nineteenth century, the growth of city needs and of the means of supplying them was even more notable. And yet, as we survey the municipal field, we are forced to admit that most of the achievements of the past have been material and temporary, and only a beginning of what must be done to make our cities truly great. Let us then, before entering upon a detailed consideration of the needs and possibilities of the modern city, take a general view of the subject before us, noting both what has been and what remains to be accompHshed.

First of all, we find that while much attention has been given to the numerous ways and means of communication, these channels of intercourse are still largely in the rough. Thus, few of our cities suffer for lack of streets, but the street plans are poorly conceived or mere haphazard growths ;

official grades have not been followed, or even established ; good pavements are limited in extent or wholly lacking, and such pavements as are put down are not kept clean and in repair. Most cities have as many miles of street railways as are commercially feasible, but both the routes and the connections with other lines are not always adapted to the natural movement of the population ; overcrowding is the rule, the safety of passengers and pedestrians is neglected, and it is often a fair question whether carfares should not be lowered. Our telephone service is becoming wonderfully quick and reliable, but on account of the high cost it is available for relatively few. The steam railway terminal facilities in many cities are inconvenient, the stations ugly and unsanitary, and grade crossings with all their delays and dangers are still the rule.

Coming next to municipal supplies, we find that water-works have been introduced in small towns to a wonderful extent, and although quantity as a rule still takes precedence of quality, it is encouraging to note that towns both large and small are now awakening to the value of pure water. The dangers of milk which has been infected, or which is of low nutritive quality, are appreciated in comparatively few communities. As for the public markets so common abroad we have little to show in numbers and even less in appointments. Municipal slaughter houses are rarer still, and perhaps but little needed, under the prevaiUng American

THE CITY AND ITS NEEDS system of wholesale slaughtering, cold storage, and distribution by a few large companies. We have some very creditable city halls and other public buildings, notably schoolhouses and libraries, but these are in the minority. A few cities have not sufficient accommodation for all the children enrolled, and the sanitary conditions of existing structures are often a menace to health and morals rather than the models which should be found in everything connected with educational systems. It is a common thing for city officials to be scattered about in rented quarters, instead of being conveniently housed in an appropriate hall.

Municipal lighting for streets and houses is far more expensive than it need be, and thus not so well provided as is desirable and would be feasible under improved conditions. Gas light and heat are beyond the means of thousands of people, and electric lights are still more expensive. The use of both gas and electricity for power would increase rapidly with the lowering of rates. Happily, lower prices are coming, both voluntarily and by compulsion.

In the removal and disposal of city wastes we are far behind our attainments in providing municipal suppUes. Only a small proportion of the communities which enjoy public water supplies have the benefit of sewerage systems, and most of the latter discharge their sewage into the nearest body of water without regard to consequences. Garbage collection is strangely neglected in the majority of cities and towns, and its final disposal is one of the greatest blots upon American municipal administration.

As a rule, fire protection of some sort follows or accompanies the introduction of public water supplies. The fire fighters of America are noted for their quickness in getting to fires, the equipment they bring, and the effectiveness with which they use it ; still, hundreds of places of fair size are without a paid fire department, many lack proper apparatus, and in many more the water supply is insufficient.

Proper building and plumbing regulations are becoming more common, but there is a great field to be developed before unstable buildings, firetraps, and bad plumbing disappear. Smoke abatement here and there receives the attention it deserves, but efforts in this direction are Hkely to be spasmodic and ill-directed. Public hygiene and sanitation are rapidly coming to the front. Among the many needs in this line, none are more pressing than the employment of well-trained, tactful, honest, energetic, and fearless health officials, and a better appreciation by the people at large of what is conducive and what a menace to the public health. Such popular education must begin in the public schools. School children may easily be taught what cleanliness is, the advantages and proper uses of sanitary appliances, and something of the relation between health and disease. This sort of instruction may be raised to higher planes

THE CITY AND ITS NEEDS as the pupils advance. Baths, playgrounds, and gymnasia, both connected with the schools and independent of them, are now recognized factors in municipal work. Colleges and universities, particularly engineering and medical schools, may well have courses in hygiene and public sanitation.

Among so many things designed more especially to maintain and protect property, health, and life and to minister to the comfort and convenience of man, the guardians of the city should not forget the higher life. Sound bodies contribute to sound minds and lofty ideals, and thus good sanitation leads up to an effective demand for municipal art. The desire for the beautiful may be met, in part, by the provision of parks and art galleries, while libraries, lectures, and music may contribute to the same and other noble ends. The beauties of nature should be made as fully available as possible, by means of parks within, and readily accessible nature-reservations without, the city. Pains should be taken to combine the beautiful with the useful in all classes of municipal construction. There should be more cooperation between engineers and both landscape and building architects.

The defects, the needs, and the possibilities of the modern city, so briefly outlined here, and presented in more detail in subsequent pages, are many and various. So numerous and complex are they that, although municipal progress must always depend primarily on good citizenship, it will rest more and more upon a permanent staff of trained executive officers, supplemented by consulting specialists of wide experience and national reputation. The municipal expert engineer and sanitarian will play an important part in the urban life of the twentieth century.

WAYS AND MEANS COMMUNICATION

CHAPTER II Streets, Pavements, and Sidewalks

The streets of a modern city are far more than mere highways for surface use. Railway cars run above and below as well as on the surface ; messages, light, heat, and power are sent through aerial or underground wires ; pipes beneath the streets bring us water, gas, and steam ; still other conduits remove liquid wastes from our dwellings and surface and subsoil water from our yards and streets. The space between the building lines, especially in the larger cities, bears an important , relation to both air and light. And finally, not to make the list too long, well-planned streets afford a most excellent opportunity to reheve the monotony of brick, stone, and asphalt with the everchanging beauty of trees, shrubs, and flowers.

The rapid growth in numbers and volume of street uses, and the tendency to do away with aerial construction as unsightly and dangerous, combine to increase the demands upon both the surface and underground ways of communication. These multiplying demands make it more and more imperative that street surfaces, and what we may call the underground furniture, be capacious,

II durable, readily maintained and repaired, and that there be as little interference as possible between the various functions of streets. Obviously there is a conflict between the surface and subsurface uses of streets unless access may be had to the underground furniture with but little disturbance to the pavement and the earth that supports it. This is possible only where a system of subways is employed. So important is this phase of street construction that its discussion has been reserved for a separate chapter. When subways are not feasible, the disturbance of streets may be lessened by systematically recording the location of all underground conduits. In many cities, not even this is done, and only after repeated experimental diggings can a pipe be located.

To provide ample accommodations for various forms of traffic, streets must be properly located and of suitable width, with easy grades and a surface well adapted for vehicles and pedestrians. Conditions affecting the public health must be given a most prominent place. In built-up areas it is often true that the location, grade, and width of streets cannot be altered except at great expense and inconvenience. The character of the surface is more fully within municipal control.

In laying out new streets the conditions essential to their maximum usefulness may be met with greater ease. Other things being equal, the location is fixed by the fact that a straight Hne is the shortest distance between two points, but it is sometimes shorter in distance as well as in time to go around a hill instead of over it. For artistic effect streets may be laid out on curved instead of straight lines ; or curves may be used to preserve a bit of natural scenery, like a clump of trees, or to follow the windings of a river or lake, or the graceful contours of a hill.

Grades, or surface slopes, are likely to be extremely obstinate factors in laying out streets. If the natural surface of the ground is flat or very hilly, it must be utilized nearly as it is found, any practicable changes of the natural levels having slight effect, unless the land be so valuable as to warrant large expenditures for grading lots as well as streets. But where the land is neither flat nor on a steep hillside, great relative changes in grade may be made with comparative ease.

From the standpoint of the usefulness of the street itself, and of its relation to health and comfort, the connection between grades and the kind of paving material which may be put upon them is of prime importance. The rougher forms of pavements are necessary for the steeper grades, in order to furnish a foothold for horses, but they are hard to clean, noisy, and uncomfortable for those who ride over them.

Finally, street grades may be made to contribute largely to the aesthetic side of urban life by substituting pleasing slopes for level stretches and, when combined with judicious location, by affording commanding views.

Wide streets and avenues, particularly when bordered with trees, add greatly to the attractiveness of a city. They also contribute to ease of communication. The width necessary for the highest degree of usefulness depends chiefly upon the volume and nature of the traffic to be accommodated. If surface railways must be placed in the streets, the width of the streets should be increased accordingly. Serious drawbacks to very wide streets are the first cost of the necessary land, grading, and pavement, and the subsequent expense of maintenance, including sprinkling and cleaning. A number of cities which have learned by experience that their streets were wider than the traffic demanded have devoted a portion of the width to grass and trees. Either the grass plot between the sidewalk and curb has been enlarged, or a strip of sod has been put down in the centre of the street. Among such cities may be mentioned Omaha, Nebraska ; Jamestown, New York ; and Columbus, Georgia.

The success of street pavements depends very largely upon the character of their drainage and foundation. If either of these is imperfect, the whole pavement is bound to be unsatisfactory. Proper drainage includes ample provision for the quick removal of both surface and subsoil water. Surface water is a nuisance in itself, and it hastens wear by the formation of ruts and hollows. In addition, it tends to rot asphalt. If water penetrates a pavement, it will make sad havoc by 14 freezing and heaving, and by causing settlement in spots. Surface drainage is secured by proper grading and by giving the pavement an arched surface. Underdrainage is provided by fiUing trenches with loose stone, or by laying either agricultural drain tile or sewer pipe, both with open joints. Frequently the soil is so porous as not to require artificial underdrainage.

As a rule, all pavements require a solid artificial foundation. Its first cost is high, but once in place it will outlast many successive layers of the pavement proper. In fact, the asphalt, brick, stone, or wood blocks which are seen in a street are only wearing surfaces, like the plank on a bridge or the carpet on a floor. The more firmly and evenly the wearing surfaces are supported, the longer they will last.

The various classes of paving material commonly employed are sheet asphalt, brick, block asphalt, granite, and other stone blocks of fairly uniform size and shape, wooden blocks, and broken stone compressed by means of rollers. The latter class is called macadam when the stones are of nearly the same size, and telford when a foundation of larger stones is used. Macadam and telford are not always included in the list of paving materials, but in view of their general use and many good qualities they seem to deserve such a place. Streets with a gravelled surface can hardly be called paved, although they may be greatly improved thereby. Both macadamized and gravelled

IS surfaces are being used more and more extensively on country roads, for which they have the necessary quahfications of low first cost and of serviceability under light traffic. Cobblestone has not been included in the Hst of paving materials, although the only apology for a pavement possessed by some of the older and less progressive cities. As generally laid, directly on the earth, it soon gets out of surface, and for this and other reasons becomes unendurable, when judged by the modern standards of smoothness, cleanliness, and noiselessness. If placed on a good foundation, cobbles would be more serviceable, but after incurring the expense of constructing a good foundation, few cities would be likely to place cobbles thereon.

Certain closely related characteristics belong to each kind of paving materials and determine its serviceability for a given location. Smooth pavements are also slippery. Their surface is easily cleansed, but, having a corresponding faciHty for scattering dust, they require frequent sweeping or washing. Hence sheet asphalt is least appropriate for steep hills, and may be very dusty on any grade. Slipperiness lessens through the range of paving materials — wood, brick, and granite blocks — till we come to cobblestone.

Where there are large volumes of heavy traffic, granite blocks of uniform size are unquestionably the most serviceable paving material. They furnish a fairly even surface, and still afford a pretty i6 sure foothold for horses, if the streets are kept clean. Care must be taken to select granite that does not wear smooth nor chip easily. Other rocks make good pavement, notably the Medina sandstone. Trap or basaltic rocks are also durable, but do not come in such uniform shapes, and therefore make a rougher surface.

Brick is considered by many, particularly in the centres of paving-brick production, to stand at the head of paving materials, although this is by no means universally conceded. For ease of traction brick is surpassed only by sheet asphalt, and it is better able to stand heavy traffic.

The objections to asphalt on account of its slipperiness have already been mentioned. These are particularly troublesome in wet or frosty weather. Unless its component parts are proportioned with the greatest care, asphalt tends to crack in cold weather and to soften and get out of surface in hot weather. Yet asphalt is a favorite, and its use is being rapidly extended. Block asphalt has some of the characteristics of sheet asphalt and of brick. In general usefulness it ranks with the latter.

Wooden pavements in America have been declining in favor for a number of years, and are now little used, even in great lumber centres. They are very popular in some foreign cities, especially the AustraHan hard woods. It is questionable whether these hard woods have been used long enough in England to determine their c 17 durability. In this country they have been given no trial worthy the name. Much of the disfavor into which wood has fallen in America is due to the improper preparation and laying of the blocks and to the lack of a suitable foundation. Rough and dirty street surfaces have been caused by these defects.

As for macadam, a well-surfaced street of this material is generally found satisfactory for light business or pleasure driving. It pffers more resistance to traffic than the regular paving materials, but this matters comparatively little where the traffic is light. For heavy traffic macadam is most unsuitable, both because of its frictional resistance and perishability. The surface layers are cut into and rolled up by the wheels, and the even surface soon gives place to ruts and hollows and alternate dust and mud. Macadam is often at its best on steep grades, because of the superior drainage and light loads at such points. It is about the only improved street surface put down in narrow strips in the centre of the street, with a shoulder of gravel or ordinary dirt between it and the curb line. In smaller towns this strip is often not more than sixteen feet wide, and it is sometimes as narrow as eight or ten feet. Certainly country roads are vastly improved by putting down a central strip of firm, smooth macadam, with a wellcompacted shoulder of earth or gravel on each side to enable vehicles to turn out in meeting or passing.

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Anything like the universal substitution of motor vehicles for those drawn by horses must be far in the future, but for certain forms of traffic it bids fair to be a feature of the next few decades and a factor that must be considered in providing street pavements. The general use of motor vehicles would simplify street problems by lessening the wear due to horses' hoofs, and diminishing street dust and dirt; but for some years to come the tendency will be for the motor vehicle to increase rather than decrease the expenditures for street improvements, owing to the resistless demand for better streets which is sure to follow its introduction.

The relative healthfulness of different kinds of pavements deserves more attention than it has yet received. One of the chief dangers to health connected with pavements is the dissemination of disease germs. When deposited on pavements, these germs may adhere to the shoes of pedestrians and to the skirts of the large but diminishing number of women who, in defiance of personal and public health, persist in wearing long dresses on the street. Disease germs may also be blown about by winds, finding hosts both out of and in doors. The particular disease most likely to be spread in this way is pulmonary tuberculosis, but diphtheria and possibly other diseases of the throat and lungs may be contracted in the same manner. It is partly on this account that ordinances against spitting in public places are being enacted by leading boards of health. Diseases of the digestive tract may be caused by the access of their specific germs to the mouths of persons on the street, but infection is more likely to occur from foods or drinks into which germ-laden dust from the street has fallen.

Street dirt itself in the form of dust is harmful to the eyes and respiratory organs. Every housewife knows how penetrating dust is. In every well-regulated city the attempt is made to keep the streets as free from dust and dirt as possible, and by means of sprinkling to keep down such dust as is inevitable. As has been suggested, the smoothest pavements are the easiest to keep clean, but their very smoothness aids the scattering of dust by every wind that blows. The natural dampness of wood blocks tends to prevent the formation and spreading of dust, but fibres broken from the blocks are hght enough to be blown about, and are particularly irritating to eyes and nose. One of the gravest sanitary charges against wood pavements has been that through their dampness and dirtiness they become breeding places for disease germs. Such conditions may prolong their life, but it is very doubtful whether any germs harmful to man ever actually multiply on street pavements. Such bacteria, it must be remembered, are parasitic, and man being their natural host, they may live but not flourish elsewhere. Sunhght and desiccation are nature's germicides ; hence smooth, dust-forming pavements, like asphalt and the best brick are 20 agents of bacterial destruction. Dampness of pavements is in itself prejudicial to health, on account of its effect upon the atmosphere and upon the feet of pedestrians.

Two other requirements of pavements, from the standpoint of health, are noiselessness and smoothness. Vehicles make little noise on asphalt or brick, but the horses' hoofs ring out loud and sharp. Sometimes brick emits a rumbling sound, believed to be due to imperfect foundation or to the rising of the pavement in an arched form due to the force of expansion. This rumbling is not considered a necessary accompaniment to brick pavements. Wooden blocks on a good foundation are relatively noiseless, this being one of their best points. Stone block pavements are noisy. Macadam is quiet.

Much that is misleading has been written on the relative cost of different kinds of pavements. Comparisons cannot be made without eliminating certain elements which vary with local conditions ; such as the amount of grading necessary, character of foundations, differences in the price of labor, material, and freight. It is obviously unjust to compare the cost of brick on a four-inch foundation of concrete with asphalt on a six-inch foundation, when equally good work demands the deeper foundation in either case, yet such comparisons are often made. Again, that brick can be laid at a lower first cost than granite blocks does not necessarily mean that brick is cheaper, since the smaller cost of repairs and longer life of the granite may more than offset its higher first cost.^

It should be the aim of every street superintendent to maintain the streets under his charge in as nearly perfect condition as possible and at a minimum expense. Wear and tear cannot be prevented, but defective spots, such as hollows, ruts, soft or broken brick, should be remedied as soon as they appear. Thorough drainage of the surface and subsoil must be maintained whatever else happens. When the pavement has become too thin or uneven to meet the requirements of traffic, the wearing surface must be entirely renewed. It is at this juncture that the value of a good foundation becomes apparent, since, if it is lacking, the pavement cannot be restored short of complete renewal. This means an entirely needless expenditure of money and a serious interruption to business.

Street sprinkling and cleaning are essential to the maintenance of pavements. Macadam roads, unless kept well sprinkled, ravel badly, during long dry spells. Accumulations of dust retain moisture and thus aid in hastening the wear of the pavement.

Of great value in determining the most suitable paving material for a given street is the taking of

^The merits of various kinds of pavements, including relative first cost, are discussed in Austin T. Byrnes's " A Treatise on Highway Construction," and also in George W. Tillson's " Street Pavements and Paving Materials."

a street census. The object of such a census is to learn the character and amount of traffic and, in some cases, the number of sUps and falls of the passing horses. When accompanied by records showing the grades of the street and yearly wear of the pavement, street censuses are of great assistance in judging the relative merits of different paving materials. Few, if any, American cities take street censuses, but the custom is common abroad.

Little space needs to be given to the discussion of sidewalks. Good drainage and foundations are prerequisites to good sidewalks, as they are to good roads, and may be secured in the same way. The traffic over sidewalks being lighter and all considerations of traction being absent, less solid work is necessary. A smooth surface, not readily worn by the thousands of passing feet, nor easily affected by the weather, impervious to water, and so graded that water will not stand on it, nor flow over it in perceptible streams, are the chief requisites for the wearing surface. These qualities may be secured by the use of stone slabs; asphalt, sheet or block ; brick, gravel, or cinders. The last two are more suitable for side streets or country roads. In addition there is a large variety of compositions, the availability of which is chiefly governed by local conditions. Gravel and tar mixed in varying proportions and combined with other materials are widely used for sidewalks, but care must be taken to proportion the parts so as to avoid softness in hot weather. Board sidewalks are prefer- 23 able to dirt, at least in wet weather, but are uneconomical, unless lumber is very cheap and all other materials very dear ; they are also liable to give rise to many accidents, through loose boards.

The width of sidewalks should not be less than four feet ; on many residence streets in villages and even small cities, the space beyond this width is of far more value if devoted to grass. As the traffic increases, the width naturally needs to be increased, particularly in business districts. The ground immediately around trees should not be covered. Neat curbs add greatly to the appearance of a street. Whatever the material of the curb, it should be set deep, on a firm, well-drained foundation, to preserve the grade and alinement. Bluestone, granite, artificial stone, and concrete, the last named protected by iron or steel built into the exposed corner, all make good curbs. When concrete is used, it may be extended horizontally toward the centre of the street sufficiently to form a gutter.