WIDTH AND CROSS-SECTION.
The width of city streets is important both on account of its influence upon the ease with which traffic may be conducted, and because of its effect upon the health and comfort of the people, by determining the amount of light and air which may penetrate into thickly built-up districts.
To properly accommodate the traffic of commercial thoroughfares in business districts of towns of consider able size, it is desirable that a street should have a width of no to i6o feet, the whole of it to be used for roadway and sidewalks. Wide streets are especially needed where, as in the larger cities, they are bordered by high buildings or are to carry lines of street railway.
Residence streets in a town of considerable size, where houses are set out to the property line and stand close together, should have a width of at least 8o to too feet in order to look well and give plenty of light and air.
The streets in nearly all large towns are laid out too narrow; they are crowded and dingy. The chief diffi culty is that the future of a street is not usually fore seen when it is located. Owners in subdividing prop erty are only anxious to get as many lots as possible out of it, and there are usually no regulations looking to the future health and comfort of residents when the street shall be built upon. In the growth of a town the nature of localities changes; residence streets become business streets, streets devoted to retail trade become wholesale streets, and mercantile districts are given up to manufacturing. If a city could be laid out com plete from the beginning it would be comparatively easy to consider the requirements to be met and locate the streets accordingly. Under existing conditions this is not possible, but a more liberal policy in planning streets would usually be found of advantage in any growth that may ensue. There is also very frequently an immediate financial advantage in the enhancement of values due to wide streets. A lot no feet deep on a street 8o feet wide will nearly always be of greater value than if the same lot be Ho feet deep and the street only 6o feet in width.
In Washington, D. C., which probably has the best general system of any American city, no new street can be located less than go feet in width, and avenues must be at least 120 feet wide. Intermediate streets,
called places, 6o feet wide, are allowed within blocks, but full-width streets must be located not more than 600 feet apart. The value of this liberal policy to the city of Washington is evident not only in the increased comfort of the people, but in its large growth as a residential city and the increased value of property in it.
While it is advantageous to have the street wide be tween building-lines, it is not necessary that the whole street width be used for ,pavements. The street pave ment should be gauged in width by the immediate necessities of the traffic which is to pass over it. The pavement should be wide enough to easily accommo date the. traffic, but any unnecessary width is a tax upon the community in the construction and mainte nance of more pavement than should be required, and perhaps diminishes the length of street which may be improved with available funds. Thus, for a residence street in general a width of 3o to 35 feet between curbs is usually ample, with a foot-walk upon each side 5 to 10 feet wide. The remainder of the street width should be made into lawns upon each side, with tree spaces between the sidewalk and roadway.
Fig. 31 shows in partial section the arrangement of a go-foot residence street for moderate traffic. For resi dence streets of lesser importance, where the travel is light and the street is only required to furnish facilities to meet the needs of its immediate locality, a less width of pavement may often be advantageously used. A pavement 24 feet wide is sufficient to accom modate a very considerable amount of light driving, and in many places, especially in the smaller towns where funds for effective improvement are obtained with difficulty, even less widths may be employed with the result of improving the streets both in appearance and usefulness. All that is really needed in such cases is room for teams to pass comfortably and to turn without difficulty. The narrowing of roadways on streets of light traffic to what is really necessary may often make possible improvements which will turn a broad sea of mud into a narrow, .hard roadway and a grass-plat. Fig. 32 shows the arrangement of a village street 5o feet wide for light service.