Land Use

Transportation and land use are closely interrelated. Transport is a part of the total process of planning. Communication facilities must exist in order to enable people to carry on with their activities ranging from earning livelihood to social contracts and recreation. Activities are spatially distributed at locations dependent upon many factors e.g. time, cost, convenience and some intrinsic site value. Locations may range from those specifically selected to those almost randomly selected. For industrial sites there must be the motive of profitability. Under use of a transport system tends to attract traffic and as this increases individual benefits decrease. When congestion sets in further development becomes necessary. At this stage extra capacity is normally provided and the cycle begins again.

Figure 1.2 illustrates why transportation planning cannot be isolated from land use planning (O’Flaherty 1974). The figure shows that whatever the land is used for, its activities generate trips – and some activities obviously generate more trips than others (1-2); these trips in, turn, point up the need for particular types of transport facilities (2-3-4); the extent to which the transport facilities are able to cope with the trip demands determines the quality or degree of accessibility associated with the land in question (4-5); of course, the accessibility associated with the land influences its value its value since, logically, the land has no value if people cannot get to it (5-6); and finally, it is the land value which helps to determine the use to which the land is put (6-1). Thus, it can be seen that the control of land use is to a large extent the key to the control of movement.

For purposes of developing traffic models and to understand clearly the physical impact transportation facilities, the planner needs up-to-date land use data on area wide basis (Paquette R. J. et al 1982). Typically, the planner will employ at least the following techniques:

• Land use survey
• Land use classification
• Vacant land use study
• Presentation and storage of land use data.

figure 1.2

Land Use Survey. Field studies are carried out to identify the type of use of all land parcels in the area. Two principle techniques are employed in the land use survey; these are inspection and inspection-interview.
The inspection method can be carried out on foot or, more commonly, ‘windshield inspection’ is accomplished by a car with a driver and an observer. The use of individual parcels is noted directly on maps, or is located on schedules that are referenced in some manner to prepared parcel maps. Scheduled sheets are necessary where land use data are stored as computer records.
The inspection-interview method can be used in areas of more intense land use, where more accurate estimates are needed of actual floor areas by type of usage. The results are recorded on schedule sheets.

Land Use Classification. In the process of differentiating the spatial arrangements and activity patterns of the urban area, it is necessary to arrange land uses in some form of standard classification. There are several land use classification systems in current use that permit detailed differentiation of usage. It is recommended that in any study area of one of these standardized classification procedures be adopted. For the purpose of the transportation planner, only major categories of land use are classified. Therefore, it will be necessary in most cases to group the results of the land use survey for analysis and presentation. Table 1.1 indicates eight broad major categories of land use. Included in this table are colour codings suggested for standardized presentation.

Table 1.1. Illustrative Major Urban Land Use Categories

Residence
Low Density	Yellow
Medium Density	Orange
High Density	Brown
Transportation, utilities, communications	Red
Retail business	Ultramarine
Industry and related uses	Indigo Blue
Wholesale and related uses	Purple
Public building and open spaces	Green
Institutionalized building and area	Gray
Vacant and nonurban land	Uncoloured

Source: Chapin, F. S., Urban Land Use Planning, 3rd Ed. University of  Illinois Press, Urbana.

Vacant Land Use Study. Prior to the design of alternate future land use plans, it is necessary to determine the development capability of existing vacant land in the area. This type of analysis is called Vacant Land Study or sometimes Development Capability Analysis.

Vacant land is classified by two chief criteria:

o Capability as related to topographic and drainage standards
o Capability as related to utilities and improvements available.

Standard planning works suggest division into prime and marginal land.
Prime land is all land that can be drained adequately with topographic slopes considered economic for building in the area. Low-lying, steep, and derelict land is considered marginal because only with large capital investment is such land capable of conversion to the prime category. Prime land is often subcategorized to differentiate between different classes of slope. For example, land at slopes still satisfactory for residential areas, 10 to 15 percent, would be unsuitable for extensive one-story industrial plants. Thus, the basic categories are expanded to Class I Prime, Class II Prime, and Marginal.

Further sub categorization is undertaken with respect to the factor of available improvements. Sub classification A could indicate all improvements available, B water and sewer only, C power only, and so on. Based on the classification scheme of the planner it is possible to identify and summarize the amount of available land in each class and category by district over the whole area, for example, Class II Prime A.

Presentation and Storage of Land Use Data. The assembled general land use patterns are stored and presented using the following techniques:

Land use maps. These are prepared from aerial photographs with major land use categories coloured as in table 1.1.

Tabular summaries of land use studies that are readily made from data assembled in the various studies. Such summaries give the planner a clear idea of the nature of the area.

It is becoming widespread practice for cities to have computerized data banks with information on:

• Persons,
• Parcels,
• Street facilities

Computerized data banks where information is coded and adapted on a street address basis can be used in conjunction with computer mapping techniques. It is possible to produce by mechanical means graphic displays of the different characteristics of the urban area down to as fine a grain as the block face.