The Fire Department’s jursidictional areas. Includes: Stations-170, Battalions-22, Divisions-9 and Regions-3. There are 198 individual polygons with 30 Stations having 2 or more discrete polygons.

Park planning areas are used to assist in calculating park fees for sub dividers in accordance with Los Angeles County Code, Title 21.

PRC 4201 - 4204 and Govt. Code 51175-89 direct the California Department of Forestry and Fire Protection (CAL FIRE) to map areas of significant fire hazards based on fuels, terrain, weather, and other relevant factors. These zones, referred to as Fire Hazard Severity Zones (FHSZ), define the application of various mitigation strategies to reduce risk associated with wildland fires. CAL FIRE is remapping Fire Hazard Severity Zones (FHSZ) for State Responsibility Areas (SRA) and Very High Fire Hazard Severity Zones (VHFHSZ) recommendations in Local Responsibility Areas (LRA) to provide updated map zones, based on new data, science, and technology. This specific dataset provides FHSZs within SRA lands only, and represents the proposed zones, subject to changes based on local hearings. A subsequent dataset release will provide the actual adopted zones. Maps of the proposed zones in SRA are available at: http://frap.cdf.ca.gov/projects/hazard/fhz.html More information about the project can be found at: http://frap.cdf.ca.gov/projects/hazard/hazard.html

The Census Bureau (http://www.census.gov/) maintains geographic boundaries for the analysis and mapping of demographic information across the United States. Every 10 years the Census Bureau counts the population of the United States as mandated by Constitution. The Census Bureau releases the results of this county as demographic data with geographic identifiers so that maps and analysis can be performed on the US population.

What is unique about LA County’s data?

It is clipped to the ocean boundary. Raw Census data includes a 3 mile buffer into the ocean, which impacts cartography.

IMPORTANT! It has been updated to the 2012 Census Geography Update, which merged Tracts 1370.00 and 9304.01 into the combined tract 1370.00. So the CT10 field actually reflects the 2012 Census update, which is used for all population products 2012 and later. CENSUS_TRACTS_2010 will reflect such change and CENSUS_TRACTS_2010_ORIGINAL will not reflect such change.

How was this data created?

This data was downloaded from Census Bureau website: http://www.census.gov/cgi-bin/geo/shapefiles2010/file-download and clipped to the County Boundary using ESRI’s ArcGIS Desktop. Two new fields were added in census tract data – area in square feet and shape length in feet. This dataset has unique identifier field “GEOID10” for each record and the census tract number fields “CT10” and “LABEL” (6-digit number and 6-digit number with decimal point, respectively).

This dataset contains rivers, streams, and water conveyance mechanisms (pipelines, aqueducts).

This dataset was downloaded, extracted and prepared from the National Hydrography Dataset. The NHD is a comprehensive effort by the US Geological Survey to manage and maintain a comprehensive, high quality, nationwide dataset for GIS mapping and analysis of water features and conveyance. While it is not perfect, and you may find a number of errors, LA County applauds this effort, and is determined to support the enhancement and maintenance of this valuable information since it supports our long-term goal of public, authoritative data. We are currently investigating the feasibility of stewarding the NHD data for the LA County region.

A description of the NHD from the USGS site:

The National Hydrography Dataset (NHD) is the surface water component of The National Map. The NHD is a digital vector dataset used by geographic information systems (GIS). It contains features such as lakes, ponds, streams, rivers, canals, dams and streamgages. These data are designed to be used in general mapping and in the analysis of surface-water systems.

This dataset contains lakes & reservoirs in LA County.

This dataset was downloaded, extracted and prepared from the National Hydrography Dataset. The NHD is a comprehensive effort by the US Geological Survey to manage and maintain a comprehensive, high quality, nationwide dataset for GIS mapping and analysis of water features and conveyance. While it is not perfect, and you may find a number of errors, LA County applauds this effort, and is determined to support the enhancement and maintenance of this valuable information since it supports our long-term goal of public, authoritative data. We are currently investigating the feasibility of stewarding the NHD data for the LA County region.

A description of the NHD from the USGS site:

The National Hydrography Dataset (NHD) is the surface water component of The National Map. The NHD is a digital vector dataset used by geographic information systems (GIS). It contains features such as lakes, ponds, streams, rivers, canals, dams and streamgages. These data are designed to be used in general mapping and in the analysis of surface-water systems.

This dataset contains hydologic points (gaging stations, gates, rock features, springs, water intakes, wells, waterfalls, reservoir points) in LA County.

This dataset was downloaded, extracted and prepared from the National Hydrography Dataset. The NHD is a comprehensive effort by the US Geological Survey to manage and maintain a comprehensive, high quality, nationwide dataset for GIS mapping and analysis of water features and conveyance. While it is not perfect, and you may find a number of errors, LA County applauds this effort, and is determined to support the enhancement and maintenance of this valuable information since it supports our long-term goal of public, authoritative data. We are currently investigating the feasibility of stewarding the NHD data for the LA County region.

A description of the NHD from the USGS site:

The National Hydrography Dataset (NHD) is the surface water component of The National Map. The NHD is a digital vector dataset used by geographic information systems (GIS). It contains features such as lakes, ponds, streams, rivers, canals, dams and streamgages. These data are designed to be used in general mapping and in the analysis of surface-water systems.

Countywide Statistical Area (formerly called Board Approved Statistical Areas) provide a common geographic boundary for reporting departmental statistics for unincorporated areas to the Board of Supervisors. They are not designed to perfectly represent communities, nor jurisdictional boundaries such as the Angeles National Forest. References below might still be for BASA – but they are now called ‘Countywide Statistical Areas’ (as of July 2016).

To learn more about this project, click on this link to go to the project page.

Download the data

The dataset below is the current final draft of the BASA boundaries. As of this December 2015 we are developing the language to have them approved by the Board of Supervisors.

BOS_COUNTYWIDE_STATISTICAL_AREAS_20170118 (zipped shapefile)

Purpose of the data

Communities are one of the most complex geographic issues in the County of Los Angeles, due to historical narratives, perceptions of value, intense public interest, and shifts over time. The County has a need to establish a consistent geographic reporting base that will enable statistics and information to reported to the Board, that attempts to represent all of the interactions but is primarily focused on reporting.

Historically, County departments provide statistics and reports to the Board for Unincorporated Areas of the Los Angeles County based upon inconsistent geographic boundaries and names. These disparities impacted the ability of the Board to work with communities and residents to communicate priorities, service levels, and effect positive change in the County.

Reporting of statistics by County departments to Board offices by consistent geographic areas will simplify reporting, improve internal and external communications, and support better decision making. Leveraging boundaries used by the United States Census Bureau will enable demographic information to be used as part of County reporting. To download the geographic building blocks for this dataset, which also provide city boundaries each year since 2010 along with relevant Census block group and tract boundaries, go to the Split 2010 Block Group/City – BASA page.

Background

The Geographic Information Officer and the LA County Enterprise GIS group worked with the Los Angeles County Board of Supervisors Unincorporated Area and Field Deputies to establish names that reflect as best as possible the general name preferences of residents and historical names of areas. A Board Motion will establish these area names as “Board Approved.” BASAs differ from the more informal “Community” geographies because:

They are primarily focused on broad statistics and reporting, not mapping of communities.
They represent board approved geographies comprised of Census block groups split by cities.
They must cover the entire unincorporated County
There can be no holes or overlapping areas
Naming Conventions

BASAs were be named according to the following recommended naming conventions:

All names will be assumed to begin with “Unincorporated” (e.g. Unincorporated El Camino Village). They will not be part of the Statistical Geography Name (so the name of the Statistical Area would be “El Camino Village”).
Names will not contain “Island” – beginning each name with “Unincorporated” will distinguish an area from any surrounding cities. There may be one or more exceptions for certain small areas (e.g. “Bandini Islands”)
A forward slash implies an undetermined boundary between two areas within a statistical geography (e.g. Westfield/Academy Hills or View Park/Windsor Hills)
Certain established names may include hyphens (e.g. Florence-Firestone)
Aliases may be defined in parentheses (e.g. Unincorporated Long Beach (Bonner/Carson Park))
Geographic Base

The BASAs were created using Census Block Groups split by cities (e.g. “Split Block Groups”) as a geographic building block. This allows users to leverage the rich information provided by the US Censu

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.