This case study describes how geographic information system (GIS) technologies facilitate urban planning in Japan. It draws on examples from three components of urban planning: city master planning, regulation revision and city planning ordinance revision. Urban planning is defined as “city planning, city planning restrictions, city planning projects and any other necessary matters concerning city planning for the sound development and orderly improvement of cities.”45 Spatial data (locational information) can be useful in all stages of urban planning from planning, consensus building and implementation to management and maintenance.
City master planning
A city master plan governs all subsidiary plans in a district, city, town or village. It typically describes the municipality’s overall policies governing:
- Land use and urban physical structures
- Rationality of traffic systems
- Placement of elements that affect community welfare
- Green belts, bodies of water, landscape and the environment
- Disaster management
Therefore, to update a city master plan and justify such an update the current patterns of land and building use need to be collected and analysed. In Japan, current patterns of land and building use are gauged from data collected through a municipality’s Basic Survey for City Planning together with census data. A Basic Survey is conducted every five years and, typically, includes population and industry, land and building use, as well as urban infrastructure such as roads and parks. In recent years, the results of Basic Surveys have been released as GIS data.
GIS data is used throughout the process of city master planning. The technology enables different maps to be laid over each other for comparison and analysis, facilitating the identification of gaps and issues to be addressed. For example, a predominance of both narrow roads and irregular parcel sizes may indicate an older neighbourhood where urban infrastructure needs upgrading or improvement.
A city can plan infrastructure upgrades using criteria within its jurisdiction, estimate the amount of work necessary, prioritize areas and create a master plan for urban area improvement and conservation. GIS technology is used to compare the draft plan with existing plans of related projects or other divisions within the local government. Finally, GIS maps are used to communicate the city master plan with its citizens for consensus building and education.
District use regulations define the purpose of a building (for example, commercial or residential) in each type of use district, as well as the permitted floor area ratio, building-to-land ratio, maximum height allowed, minimum parcel size and so forth. As any changes to these district use regulations impact the rights of private land and building owners, the reasoning behind revisions must be meticulously analysed and documented. GIS technologies support local governments in this exercise by providing relevant data. The results of GIS analysis show the effects of a change in regulation both numerically and visually, contributing to consensus building.
Height control districts have restrictions on the minimum or maximum height of buildings to preserve or improve an urban environment. In the past, the absence of such regulations resulted in high-rise residential buildings sprouting up in metropolitan centres, sometimes changing the character and quality of the surrounding environment. Many local governments are now adopting height control regulations, for which data on existing building heights is crucial. Airborne laser scanning (capturing 3D data of large areas) is helping local governments measure and map the height of existing buildings. Combining this data with land use, parcel size, roads and other information using GIS enables the generation of multiple scenarios based on different height control parameters that can be examined before adopting or revising height control regulations.
City planning ordinance revision
To ensure locally appropriate urban planning, city planning ordinances in Japan are set by local governments within the parameters of national legislation. As a general rule, an ordinance is required when rights are restricted or when administrative obligations or duties are created.
There are different kinds of local city planning ordinances: those that outline a municipality’s urban planning principles and measures; those that describe methods and procedures for community participation in the planning process; and those that list standards and codes governing land development projects and land use, or list local standards and codes on land development based on the City Planning Act (called delegatory ordinances).
GIS technologies also support local governments in the preparation of compound ordinances. While sharing traits with delegatory ordinances, compound ordinances are issued by local governments under legislative powers vested by the Local Autonomy Act. When setting new or revised standards and codes regarding development and land use, the number and distribution of buildings or plots that would meet the new criteria must be demonstrated. As these ordinances could potentially restrict private rights, GIS technologies are used to validate the rationale behind the proposed codes and standards.
*)This case study has been provided by Kokusai Kogyo Co. Ltd. (Japan) and is an extract of the World Economic Forum report:The Future of Urban Development & Services: Urban Development Recommendations for the Government of India and was written by Alice Charles, Cities & Urban Development Expert, Urban Development Lead, World Economic Forum & External Board Member, NAMA
**) Featured image: Vidur Malhotra (cc)
***) Recommended read: Japans Super Smart Society 5.0