https://ia800503.us.archive.org/30/items/structuregrowtho00unitrich/structuregrowtho00unitrich.pdf
Introduction - The Technique Used in Analysing the Structure and Growth of Residential Neighborhoods in American Cities
Is the
American city an entity whose different types of land uses and residential
neighborhoods are arrayed in definite patterns or is it a disorganized mass of
structures scattered about in hit or miss fashion? The answer to this question
requires the formulation of principles of city structure and the examination of
the fundamental theories of the physical character of the urban community.
Inquiry
into the character of the internal organization of cities, however, is not
merely an academic matter. There is a whole series of vital urban problems, the
solution of which depends upon proper analysis of the apparent riddle of the
internal nature of American cities. The selection of areas for slum clearance,
the determination of mortgage lending policy by areas, and decisions in regard
to zoning or rezoning of sections for given types of land use all depend upon
the forces governing the interrelationship of different types of areas and the past
and prospective movements of different types of neighborhoods.
This
monograph has the two principal objectives of furnishing the tools for analysis
and developing principles of general application that may be used in the
intelligent examination of the internal structure and growth of American
cities. In its twofold purpose, this study will first suggest a series of techniques
by which the terra incognita of a city may be mapped and charted, and the
growth of its various parts measured. Secondly, it will seek to develop
principles of urban structure and growth that may give an insight into the
causes of the present arrangement of land uses and residential neighborhoods in
American cities.
The present
study is based upon the past performance of the myriad forces governing
neighborhood interrelationships and movements in city growth. The series of
techniques which form the tools for analysis are designed to bring order out of
chaos and to provide an approach to an understanding of the basic forces. The
reliability of the principles formulated, however, will depend upon the effect
of the impact of new forces and upon their being tested by further study. In
years to come, continued eradication of slum areas or a cessation of population
growth may foster conditions favoring a doubling back of high grade residential
areas rather than a continuation of growth in line with past experience. Or, it
is possible that common use of aircraft or other means of rapid transit may
result in a greatly accelerated decentralization.
The
techniques suggested and employed in this study, and the principles of urban
structure and growth suggested are not set forth as the only method of attack
upon the difficult question of the nature of the structure and growth of
cities. There are innumerable roads by which the subject may be approached.
Rather than spend too much time in debating as to the choice of routes,
however, the definite order of procedure outlined below is suggested because it
has proved of value when applied to the solution of practical problems.
For the sake of clarity in exposition, this monograph is divided into two major sections. The first part analyzes the city for the purpose of determining its internal structure and the relationships of its various neighborhoods to each other. The second part investigates the movement or growth of the entire city and its component parts. An appendix will acquaint the reader with methods of compilation and provide him with definitions of the basic data used throughout. It will also give the reader a clearer understanding of the method of construction of the several types of maps utilized in the different stages of the technique. A technique developed by the Division of Economics and Statistics of the Federal Housing Administration as an aid in the selection of mortgage risks is also outlined in the appendix. A map supplement contains numerous illustrations for further clarification of the text. This introduction, as its title indicates, outlines the technique followed in the body of the monograph.
The order of treatment of the subject matter of this monograph has a special significance because there is a definite sequence in the successive steps that are used in analyzing city structure and growth. The section of this monograph relating to the structure of the city is placed first because, primarily, it is necessary to ascertain whether there are any definite patterns of land uses and neighborhoods in a city before the movement of these uses and of residential neighborhoods in particular, over a period of time, can be studied.
The first section begins with an inquiry into the structure of a city. It is necessary first to ascertain the extent of the area covered by urban buildings. In other words, the ground plan the configuration and shape of the city must be visualized before its component parts can be analyzed. The first step in the technique, therefore, employs the use of urban "topographical," "land coverage," and "settled area" maps. As previously stated, the method of construction of these different types of maps is outlined in the appendix. These maps reveal the shape of the city and the interstices within the urban mass. From these maps, delineating the urban area as a whole, current generalizations as to the shape of cities whether they are rectangular, circular, or star-shaped may be thoroughly tested.
Having
examined the city as a single unit, the second step in the technique breaks
this undifferentiated body into its component parts to establish the pattern of
land use. "Land use" maps are utilized to reveal the ground area
occupied by each type of use, and the extent to which the different uses are
separated or intermingled. Such maps also serve as a guide in formulating a
generalization with regard to the pattern of land use. The generalizations thus
evolved serve to illuminate the spatial relationships between commercial and
industrial functions and to segregate the residential areas from other forms of
land use.
Having
segregated the home areas from the general urban mass for study, the third
major step in the technique differentiates the several types of residential areas
on the basis of their essential housing characteristics. The analysis of these
home areas and the formulation of generalizations apparently governing the
distribution of the several types of residential urban areas are the main
subjects of this monograph. (..)
1 See Report of the Urbanism Committee to the National Resources Committee, Our Cities, Their Role in the Rational Economy (Washington, D. C., June 1937), p. 5.
"If the observer views it from an airplane, the typical American city will appear as a sprawling mass of structures of varying size, shape, and construction, crisscrossed by a checkerboard street pattern which here and there assumes irregularities. The cells or blocks into which the city is divided seem to lack any organic grouping into units, even though the variations of the terrain may suggest the articulation of series of blocks with one another. The general impression to be derived from the arrangement is that of unimaginative, stereotyped, mechanical monotony, only rarely will one find even a partially organic pattern throughout."
2020-05-17
