Page:John Nolen--New ideals in the planning of cities.djvu/18

NEW IDEALS IN THE PLANNING OF other physical data, is, in most cases, considered indispensable. Yet, for a city, with conditions far more complex, a topographical map is seldom to be had. There are probably not a dozen cities in the United States that have topographical surveys of any real value as a basis for a comprehensive city plan. It is true that the topographical maps of the United States government, prepared by the Geological Survey, can be had for cities in many sections of the country, but the scale is so small (usually one or two miles to an inch) and the contour interval so wide (usually 20 feet or more) that they are of little worth to the city planner. One of the initial requirements in the replanning of cities, then, is the preparation of topographical maps giving full information as to the present physical conditions. On such a map there would be placed also all other important data controlling or affecting the city plan.