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Subdivision Map Act


Act that promotes and regulates the construction and design of real property improvements of public property. The act requires that any public building being constructed cannot place an undue burden on the public and the taxpayer. The act gives local government bodies the right to institute regulations for land use.


The Subdivision Map Act is an aspect of the California Civil Code that regulates the development of subdivisions with two or more parcels/units.

First, it designates who is responsible for the regulation of subdivisions:

“Regulation and control of the design and improvement of subdivisions are vested in the legislative bodies of local agencies. Each local agency shall, by ordinance, regulate and control the initial design and improvement of common interest developments.” (Civil Code 66411)

All regulations are intended to protect the health and safety of the public, while maintaining the rights of property owners. The policy set by these local agencies must follow a city’s General Plan.

The Subdivision Map Act sets forth policies relating to access, including alleyways, driveways, garages, drainage, electricity, sewage, water, gas, and local schools. It limits the regulation of subdivisions of five or less lots, however, to “the dedication of rights-of-way, easements, and the construction of reasonable offsite and onsite improvements for the parcels being created.” (Civil Code 66411.1. (a))

The Subdivision Map Act requires that developers provide the city with two types of maps prior to subdividing the property:

Tentative map

Final map

A final map must be approved in order for a developer’s land to be approved for subdivision. To obtain this approval, a developer must meet all the requirements of the Subdivision Map Act before the tentative map expires.

Two Main Reasons for Subdivision Map Act:

To organize the layout of the city. This includes the direction of streets, the location of vital services (police department, fire department) and utilities (street lighting, stop signs, etc.).

To divide and organize land appointed for public and private use.

The subdivision map act establishes standard procedures relating to the sale of subdivided land. The act gives authority to local governments to make decisions regarding the design and improvement of common interest subdivisions and for subdivisions that require a tentative and final or parcel map. Furthermore, the act establishes basic guidelines by the state government and gives authority to local governments to create specific laws for such implementation.

The subdivision map act confers autonomy to the local government to make decisions regarding the subdivision of land including the design of property, sewer/drainage system, trash system, and other important aspects of a property that relate to the specifics of a city. This portion of the subdivision map act brings power to the local level, where local legislators are expected to know what is most important for their city.

Tentative Map- The first draft of a parcel map is called the tentative subdivision map. First drafts are similar to rough drafts and are in no way indicative of the final map. Although the map in no way is considered the final copy, the tentative map should include the following:

Legal description of property (i.e. property’s boundaries begin and end)

Streets which run through, counter, parallel, perpendicular of property

Existing drainage, sewer and utility areas

Proposed changes to the drainage, sewer and utility areas

Proposed property use

Water source

The sub-divider must divide the land based on the standards set forth by the city. When subdividing large land that runs through multiple streets, the sub-divider will usually make changes to the streets to allow for easy access to and from the property. After accounting for the streets, curbs, and public space which may run through the land, the developer if approved by the city, can subdivide the land. Land must be divided according to the standards set forth by both the state and local government.

Final (Tract) Map

Before the tentative map reaches its expiration date, a Final Map is needed by the jurisdiction. All certificates, statements, and dedications are required to be signed as well as notarized in order to be approved. If there are improvements that need to be done to the subdivision, the work must be completed  before the map is approved. If the work will not be completed in this timeframe, an improvement agreement must guarantee that the work will be finished along with cash, bonds, or an irrevocable letter of credit among other measures that act as a safeguard for the construction. Once these steps have been taken, an engineer who works for either the city or county must determine that the map is in compliance with the guidelines set by the SMA. Once this takes place the map then is passed down to the jurisdiction during a public hearing where it will either be approved or denied.

Case Law As It Relates to Subdivision Map Act

Case Review: People v. Byers (1970)

The case, People v. Byers (1979) 90 Cal.3d 140., involved a situation in which land was illegally subdivided and sold.

A property owner (Byers) illegally subdivided his land into four parcels and transferred them to his son. Together, father and son sold the parcels without following the procedures of the subdivided lands law. Knowing that he had violated the law, the father fled town to avoid prosecution. The son did not flee, and was tried in court for illegally subdividing and selling land.

The son argued that he had been unaware that his actions were unlawful. Nevertheless, the Superior Court found the son guilty. The son appealed. The Court of Appeals cited the Subdivision Map Act to argue that there was sufficient evidence to sustain the convictions. The court upheld the lower court’s ruling and the son was held liable for aiding and abetting a criminal (his father).

What Does Subdivision Map Act Do?

Does not allow for the construction of a building to begin without the Parcel Map or Final Map being recorded (Model homes are excluded)

Landowners that may have their property rights infringed upon are set to receive a public notice as well as a motion of appeal

Confirms that the proper enhancements are made to the land in order to mitigate the costs of the taxpayers

Orders Soil and geotechnical investigations

Handles design of the improvements to subdivision

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