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Urban Planning: A GIS experience

Ajit Jere and Ajay Sarin
Autodesk India, Bangalore.

Geographical Information Systems are computer aided decision support and planning tools which integrate data from maps (spatial data) and other auxiliary data (attribute data) for a geographical area of interest. They can be used to create and maintain geographic databases and are eminently suited for what-if-analysis in any planning related activity.

Once the GIS package integrates the spatial and attributed data, the planner has a powerful tool which can be used for information dissemination or analysis. By querying the geographic database in several ways the planner can present the available information in a variety of formats: as printed tabular reports, graphically as map display and map outputs on paper.

The analysis capabilities of a GIS package allow the planner to address what-if questions and work out a variety of action plans in a scientific manner. A number of problems can be solved by geographic analysis.

Typical examples are:

  • Town ship development
  • Relationships between agricultural parameters such as yield and salinity
  • Land capability analysis
  • Site locations for facilities
  • Environmental problems such as animal migration.

Here we discuss how GIS package can be used for managing rezoning exercise in a neighbourhood property.

Urban Planning Application
Problem Scenario Zoning is the classification of an area into land use districts. Examples of general land use districts. Examples of general land use districts are residential, industrial, commercial, educational and public open spaces. These can be further classified into more detailed categories e.g. Residential which may further be classified as HIG, LIG, MIG and EWS etc.

The responsibility of urban zoning rests with City Corporation or town planning authorities. The city’s zoning plan includes a list of all the different zoning categories, as well as a zoning map showing the boundaries of different land use zones. The plan helps to regulate the use and development of land and ensure that adjacent land uses are compatible.

Picture No.2: Rezoning Map

Over a period of time, changing population and commercial needs often necessitate changes to zoning plan. Such changes are known as rezoning. For example, a city layout might need a new school to accommodate the growing number of school children in the area. The city administration could decide to use a vacant agricultural property as a site for school. The zoning of the plot would be changed from agricultural to a public use category. Private individuals or companies can also apply for a property to be rezoned by competing and submitting a rezoning application form to the city’s planning department.

When the city receives an application to change the zoning of a particular property or the administration itself decides to change the zoning plan, a formal rezoning process begins. Primarily, the proposed land use must be compatible with land uses of the surrounding area and fit in with the city’s zoning plan.

To protect the right of citizens, the city must inform affected property owners about rezoning and allow them to express any concerns or objections at a public hearing. The city uses letters sent by certified mail, legal notices on the property itself, and a notice published in a local newspaper to inform residents and property owners within a specified radius of the property of the public hearing.

The Process
The zoning process has become much simpler since the GIS software solutions are available. All the information that was previously recorded on separate paper map is now contained in a single integrated spatial database that is linked to the city’s parcel database. The database contains property, owner and zoning data.

Picture No.3: City Spatial Database

In a typical real life application, when the planner receives a rezoning application for a vacant residential property to be changed to commercial land use, the GIS package makes it easy for the planner to quickly assemble a list of properties within a stipulated buffer distance around the applicant’s property and automate the task of mailing zoning notification letters with Microsoft Word and Seagate Crystal Report. Because the GIS package has buffering capabilities built into its selection filter mechanism, planner does not even have to create a separate buffer to generate the property list. The GIS product saves the list as a Microsoft Access database table, which the planner then uses to extract information for mailing list from the city’s parcel database. The tight integration between the GIS software product, Microsoft Word and Access and Seagate’s Crystal Report allows the planner to carry out required task more easily and quickly.

Broadly the planner application, containing the parcel information of the applicant’s property

  • The rezoning application, containg the parcel information of the applicant’s property
  • The city’s property database containing property and street data
  • The city’s parcel non graphic database containing property and owner data
  • The planning department’s standard mailing letter head to inform affected land owners
  • The planning department’s standard rezoning notification letter in digital format

After putting above information in place the planner can conduct following task using GIS tool

  • Locate the property of applicant who wants change of land use
  • Select the affected property with specified buffer distance for new land use
  • Create rezoning area map
  • Create Mailing List of affected property
  • Create Mailing Letter to affected property

Summary
The above exercise illustrates the importance of computer aided tools for day-to-day activities. The planner can look for different options and choose the best suited for the end result. The automated process is not only faster but can be monitored effectively in any eventuality.

The above application using GIS tool is one of the many areas where such utilities can be used for managing planning activities. Few of these are Urban Information System, Land use monitoring system, Tax Collection System, Land Registration and Monitoring System, Urban Holding Application etc.