Subdivision Practice in Town Planning

Subdivision and site design standards are used by communities to regulate how parcels of land are divided into developable lots, and how those lots are subsequently designed and laid out through the development process. Subdivision typically includes the creation of a sketch plan (showing basic lot layout and provisions for public infrastructure), and subsequent creation of a more detailed preliminary plat (indicating building footprints and specific measurements), and then culminating in a final plat that creates the new lots. Abbreviated procedures are typically established for minor subdivisions that involve the creation of just a handful of lots. 

Site design standards are related and define the basic parameters for development on individual lots, including maximum or minimum lot size, how buildings are situated on a lot, traffic and circulation patterns, pedestrian connectivity, preservation of open areas, and avoidance of hazardous areas. 

Communities increasingly consider hazard mitigation when adopting site layout standards. For example, applicants are required to avoid mapped hazard areas (like floodplains) in new development or to develop strategies to mitigate the hazard risk. In terms of hazard mitigation, the primary benefit of adopting effective subdivision and site design standards is to ensure that new development occurs in a high quality, well designed manner that avoids potential high hazard areas, in addition to meeting other important community goals. Other benefits include: 

• Effective at managing new development in growing communities. Clearly defining hazard areas allows elected officials to say no to new development in unsafe areas. 
• Provides additional protection for defined hazard areas without negotiation on a case by case basis. Approval criteria can be stated in the code, making expectations clear to the developer and the decision makers. 
• Can be tailored to fit a common set of review procedures. Adding natural hazards as a component of existing subdivision regulations can be done relatively easily through an ordinance amendment. 
• Relatively easy to maintain over time, following initial adoption.

Subdivision of Land 

Earlier in every city much land is either vacant or inefficiently used – speculative prospect. Various methods have been proposed to emphasize taxation on land. Necessity for regulations over the subdivision of urban land was urgent, since use and development of land constitute a right best owed by the community upon the individual and this right may be withdrawn if he violates the conditions. A piece of land divided into more than 8 parcels, each of which is to be sold separately is called Layout, whereas less than or equal to 8 divisions is called a subdivision of land. 

To the land developer the subdividing of land is primarily a matter of profit. To the community, it is a matter of public concern, activities determine quality of living. Many elements in the overall plan are realized at the time the land is developed, highways, streets and alleys, sewer and water lines, power lines, schools, transportation lines, police and fire protection etc. 

Subdivision Procedure 

• Land is surveyed 
• Officials records consulted – proposed highway, special easements, right of way etc. 
• Amenities, cultural and social facilities 
• Refer Subdivision ordinances
• Planner or engineer to prepare preliminary plan – include size, shape no of lots, location of streets, radii, drainage, utilities etc. 
• Estimate is prepared – cost of development 
• Tentative map is file with local agency – approval obtained else incorporate suggestion made, if any and re-submit

Sub Division Practice 

Local Administration and Social Welfare Department Kerala building rules 1984. In the case of residential development, every plot shall have an average width of not less than 7.5 m and an average depth of not less than 12m. In the case of row housing where side open spaces are not required , plots shall have an average width of not less than 4.5 m and an average depth of not less than 10 m. Area of any newly subdivided, reconstituted or building plots shall not be less than 1.2 Ares (120 sq.m). Every plot shall have a frontage of not less than 6 m on any abutting street. 

According to Rule no 27 of KMBR, for developments including land subdivision and plot development for residential use.- All new developments including land subdivisions and plot developments shall be subject to the following, namely:- 

1. The area of any newly subdivided plot, reconstituted plot or building plot shall be not less than 125 square meters with an average width of 6.m: provided that for row housing where side open spaces are not required, it is sufficient if the plot has an average width of 4.50 m. 
2. Every plot shall have a frontage of not less than 4 meters on any abutting street. 
3. Every street shall have not less than 7.00 meters width and shall be motorable. 
4. When the area of the land under development work, layout or subdivision is 50 Ares or more, ten percent of the total area shall be provided for recreational open spaces and shall be suitably located to be accessible the residents of the layout. Provided that while considering the area of the land, the area of any contiguous land belonging to the same owner, though not proposed immediate development shall be taken into account. 
5. The recreational open space to be provided under item (iv) shall have an access as if it were a separate plot and as far as possible it shall be in 1 piece and in no case less than 2 areas in area with a minimum width of 6 m. 
6. The layout or subdivision proposal shall be in conformity with the provisions of published or sanctioned development plan for the area and if the land is affected by any reservation for a public purpose, the Secretary may agree to adjust its exact location to suit the development but not so as to affect its area. 
7. The street junctions shall be splayed or rounded off to give sufficient turning radii and sight distance for vehicles and the side if the splay shall be a minimum of 4 meters for roads up to 10 meters and shall be a minimum of 1 meters for roads exceeding 10 meters width. 
8. In the case of lay out or sub division of land having an area of two hectares or more a suitable plot for an electric transformer shall be provided. 
9. In the case of development permits, approval of the District Town Planner shall be obtained for land up to 0.5 hectares in area and approval of chief Town Planner shall be obtained for land exceeding that area. 
10. If the site forms part of approved layout, copy of sub division layout shall be enclosed along with the plans for approval. 
11. Adequate arrangements for surface water drainage shall be provided.

Residential Plots 

The area of any newly subdivided plot, reconstituted plot or building plot shall be not less than 125 square meters with an average width of 6.00 meters, provided that for row housing where side open spaces are not required, it is sufficient if the plot has an average width of 4.50 meters. Every plot shall have a frontage of not less than 4 meters on any abutting street; every street shall have not less than 7.00 meters width and shall be motorable: Provided that in the case of cul-de-sacs with length not exceeding 250 meters, it is sufficient if the street (cul-de-sac) has not less than 5.00m width and in the case of cul-de-sacs not exceeding 75 meters, it is sufficient if the street (cul-de-sac) has not less than 3.00 meters width. 

According to Rule 29 development including land sub-division and plot development for industrial development.- All new developments including land sub divisions and plot developments shall be subject to the following:- 

1. The width of every new street, public or private, intended for use as a cart or carriage way giving access to or through an organized industrial area with not less than six constituent units, shall be minimum 10 meters: Provided that in the case of small industrial units or cul-de-sac not exceeding 150 meters length, the minimum road width shall be 7 meters. 
2. The minimum size of industrial plot abutting street shall be 400 sq. meters in extent with a width of not less than 15 meters: Provided that the minimum plot requirement in item (ii) shall not apply to small industrial units. 
3. In industrial layouts a place for installation of transformer shall be provided in consultation with the Chief Electrical Inspector or an officer authorized by him. 
4. The approval of the Chief Town Planner or an officer authorized by him shall be obtained for the layout of industrial streets and land sub-division exceeding five plots. Note:- For the purpose of these rules small industrial unit means an industrial unit classified as such by Government from time to time or an industrial unit not included in Schedule 1 of the Factories Act, 1948. 
5. The usage of plots proposed for development or redevelopment shall be governed by the provisions contained in the development plan or detailed town planning scheme prepared for the locality. Provided that where no such plan exists, the usage of plots shall be as approved by the Chief Town Planner or an officer authorized by him.