Methods of conducting density survey or land use survey of a city

The word land use is related mainly to the use to which the land in a certain region at a certain time is put. Land use survey is generally done for the purpose of land use planning.  Land use survey is for the preparation of land use maps and is the basic planning survey.

  •  The mapping will take place on the old land use map sheet of 1: 10,000 scale
  •  The mapping of the settlements will be somewhat detailed. Level 1 classification of land uses like residential, commercial, manufacturing, and public semi-public, recreational, transport and communications, etc.

Method of conducting land use survey:

  •  A team of two persons should be provided with a clipboard, a map sheet, field survey note sheet, colour pencils, black pencils, and eraser.
  •  On reaching field the stretch of road along the survey route should be numbered for reference on the map.
  •  The details in the first part of the survey note sheet to be filled and the reference numbers are noted.
  •  New buildings and user should be marked in the map with proper color and notation and note should be kept in the survey field sheet as per the reference number.
  •  Drawing a diagonal line on the plan of the building should indicate any demolition of building.

b) Density survey of a city:

Density means the number of objects – houses, room, persons etc per unit of space or per unit of geographical area. Density in certain limit is desirable for planning to concentrate the infrastructure in particular area. Detailed information about density is of vital importance for planning purposes, because most of the planning proposal based upon it for reducing congestion. The study of density may be divided into residential and non-residential.

Land Use Planning

Methods of conducting density survey of a city:

Under residential density:

a)     accommodation density survey:

  •  The first step is to obtain 1:2500 scale map of the whole of the build-up area. All predominantly non-residential areas with little of residential population should be blocked out.
  •  The predominantly residential areas should then be divided into areas of similar types. The areas should be similar as regards to house types and tentative observation of density.
  •  Observation should also be made with objective of choosing land to include the house plots themselves, the road giving access to them, and any purely incidental open spaces. Small open spaces in the centre of house blocks used by the habitants should clearly be included. The best test is to consider whether a particular open space is used in common by the inhabitants of few houses which surround it or by the inhabitants of a considerably wider area, in which case it approaches the character of an ordinary local open space, and should not be considered as incidental open space.
  •  To count the number of habitable room in each sub-division. Bedrooms are of course the habitable rooms proper, but it is sometimes reasonable to include a kitchen, if it is also used as a living room.
  •  It is not really necessary for the purpose of this survey to count the number of habitable room in each house. A representative sample survey will do.

b)     Population Density Surveys

  • Conventional technique:
  •  The demarcation of sub-areas and measurement of their areas are to be carried out.
  •  The people living in the area are to be determined for each block. This should be done by direct sample survey.
  •   Frequent revision of info.obtained from the population density survey.
  •  A simple division of the total population with the area gives population density in person per unit area.
  •  The ratio of population density with accommodation density gives the occupancy rate in person per habitable room; this information can be used in the calculation of areas required for reception of overspill resulting from reduction of occupancy rate in crowded areas.

Modern technique

  •  Use of aerial photography gives the density of any area almost accurately and the time required for the information to collect is less.
  •  It is possible to count the number of houses from the large-scale aerial photography, which gives the small unit of building in block.
  •  A random field survey is done to find out the average population in a small unit of these building
  •  Total population is thus found out by multiplying number of house with the number of people per house.
  •  Area is calculated mechanically from the photograph directly or the available land use map.
  •  Thus density is calculated.
  •  The use of remote sensing data of resolution 5.8 mt from IRS-1D Panchromatic Camera (PAN). Or the 1-to 4-mt resolution data from IKONO can be used to count the density.

For carrying out non-residential density survey:

  •  A map of 1:2,500 is required. But for densely developed area a map of 1:500 is suitable.
  •  The information of total floor areas for each class of land use is required.
  •  The intensity of use of each block of land is required in terms of its FSI.
  •  No calculation of area should be attempted in the field.
  •  But if the upper floors are of less area than the ground floor, they should be shown as proportion of ground floor.
  •  The procedure should be to make all the information required for on the field sheet so that the tables of floor areas can be prepared from them in the office.
  •  It is not necessary to enter to every floor of the building. It can be assessed from the ground by looking the window of the upper floors or asking the information from the ground floor inhabitants.
  •  The measurements of the area of buildings and sites can be carried out in the office by measuring the areas from field sheets, after the fieldwork has been complete.

Read about: Land Use Planning, Land Use Planning in India,  Zoning of Land for OD Survey, Traffic Volume Count,