Los Angeles County includes 88 incorporated cities and over 2,600 square miles of unincorporated area. The majority of the County’s 10 million residents live inincorporated cities, and about 1 million residents live in unincorporated areas. To ensure that communities across the County received equal representation in the Parks Needs Assessment, the County was divided into individual Study Areas. These geographic boundaries were developed using a GIS-based process that considered existing jurisdictional boundaries such as supervisorial districts, city borders, and County planning areas alongside information about population.The initial Study Area boundaries were reviewed by the Steering Committee at their first meeting. Revised Study Area boundaries incorporated Steering Committeecomments and resulted in a total of 189 Study Areas. However, due to its annexation into the City of Santa Clarita, one unincorporated community was later eliminated, bringing the final total number of Study Areasto 188. The process of establishing Study Area boundaries is illustrated in Figure 5. Each incorporated city was initially assigned a single Study Area. Cities with population over 150,000 were split into two or more Study Areas, to create a more even distribution of population among Study Areas. Each of these larger cities was allocated a number of Study Areas based on their total population:»» City of Los Angeles: 43 Study Areas»» City of Long Beach: 5 Study Areas»» City of Glendale: 2 Study Areas»» City of Santa Clarita: 2 Study Areas»» City of Lancaster: 2 Study Areas»» City of Palmdale: 2 Study Areas»» City of Pomona: 2 Study Areas»» City of Torrance: 2 Study Areas»» City of Pasadena: 2 Study AreasFor each of these cities, project consultants suggested internal Study Area boundaries based on input from city staff, geographic barriers such as major roadways, Citydeveloped boundaries such as council districts or planning areas, and population distribution. Final determination of the internal boundaries of the Study Areas was at the discretion of city staff.Unincorporated communities in the County were evaluated based on population size and geographic location. Each of the 187 incorporated communities was addressed as follows:»» Geographically isolated communities with small populations were added to the Study Area of the adjacent, like-named city. A total of 18 cities agreed toinclude an adjacent unincorporated community within their Study Area boundaries.»» Distinct and/or geographically isolated communities with larger populations each became an individual Study Area. Any of these communities with more than150,000 people was split into two Study Areas, similar to what was done for large cities.»» Geographically adjacent communities with small populations were grouped according to community name and geography, population distribution, andstatistical areas.»» Each Study Area was assigned a unique identification number, illustrated in Figure 6, Figure 7, and Table 1.

This layer contains information for locating past and present legal city boundaries within Los Angeles County. The Los Angeles County Department of Public Works provides the most current shapefiles representing city annexations and city boundaries on the Los Angeles County GIS Data Portal. The Department also provides large format city annexation maps (pdf) on its FTP site. True, legal boundaries are only determined on the ground by surveyors licensed in the State of California. Numerous records are freely available at the Land Records Information website, hosted by the Department of Public Works.Principal attributes include:NO: corresponds with numbers on the tables displayed on City Annexation Maps.ANNEX_No: is a text version of the "NO" field listed above. Because this field is only used for the Long Beach and Los Angeles Annexation Maps, this value is null for all other cities.NAME: is the official name under which the annexation was filed.TYPE: is used to indicate which legal action occurred.A - represents an Annexation to that city.D - represents a Detachment from that city.V - is used to indicate the annexation was rendered Void or withdrawn before an effective date could be declared.33 - Some older city annexation maps indicate a city boundary declared 'as of February 8, 1933'.ANNEX_AREA: is the land area annexed or detached, in square miles, per the recorded legal description.TOTAL_AREA:is the cumulative total land area for each city, arranged chronologically.SHADE: is used by some of our cartographers to store the color used on printed maps.INDEXNO: is a matching field used for retriving documents from our department's document management system.STATE (Secretary of State): Date filed with the Secretary of State.COUNTY (County Recorder): Date filed with the County Recorder.EFFECTIVE (Effective Date):The effective date of the annexation or detachment.CITY: The city to which the annexation or detachment took place.FEAT_TYPE: contains the type of feature each polygon represents:Land - Use this value for your definition query if you want to see only land features on your map.Water - Polygons with this attribute value represent internal navigable waters. Examples of internal waters are found in the Long Beach Harbor.3NM Buffer - Per the Submerged Lands Act, the seaward boundaries of coastal cities and unincorporated county areas are three nautical miles (a nautical mile is 1852 meters) from the coastline.