California Protected Areas Data Portal


CPAD Data - Structure and Standards

What is contained in CPAD and how the database is generally structured are described below.  This information below is a digest from the CPAD User Manual (PDF, 1mb).


The key elements in the CPAD data definitions are as follows (you can also download the summary flyer, What's in CPAD - 2.5mb PDF):

Agency Types:   CPAD contains data on over 1,000 agencies and organizations. These are categorized by level (federal, state, county, city, special district, nonprofit, private, unknown), and by agency subtypes:

Federal Agency (no subtypes)
State Agency (no subtypes)
County Agency (default);  County Agency - Other; County Agency - Parks
City (default);  City - Other Agency

Special District subtypes:

  • Airport District
  • Cemetery District
  • Community Services District
  • Fire District
  • Flood District
  • Irrigation District
  • Metropolitan Planning Organization
  • Open Space District
  • Port/Harbor District
  • Recreation/Parks District
  • Regional Park District
  • Sanitation District
  • School District
  • Special District - Other
  • Transportation Agency
  • Water District

Non Profit - Conservation, Non Profit - Land Trust; Non Profit - Other

Private - Other


“Protected” Status:    Lands in CPAD must be protected for open space purposes through fee title ownership (easements are in a separate database). The purpose for the fee title ownership must be primarily for the continuation of open space values. CPAD “protected” status does not mean a specific level of conservation for biodiversity values. Instead, “protection” in CPAD refers to a general commitment to maintain the property for any of a wide range of open space uses.

 Several caveats about land ownership and CPAD:

  • Leases, contracts, term easements and regulatory controls adopted through land use planning processes are not considered “protected lands” in CPAD, as they are not fee ownerships (even though they may provide important protection to open space lands) 
  • Lands owned by public agencies that may have some open space values but that are not explicitly owned or held to protect those values are not included in CPAD. (Examples:  a utility easement, unless it is also used or planned to be used as a non-motorized trail corridor intended for public use; a school with no joint use agreement for use of its play areas; a wastewater treatment plant; military installations). 
  • U.S. BLM lands are all included in CPAD, even though significant areas of these lands may be sold or traded over time to better configure and conserve public land resources. Similarly, U.S. Forest Service ownerships are included even though actively harvested (a legitimate resource-based open space use). 
  • Particularly for federal lands, only ownerships are included in CPAD – proclamation or planning boundaries are not part of CPAD (these are areas of possible future jurisdiction or management, but often encompass private lands).

Gap (Biodiversity Protection) Ranks:   CPAD contains initial USGS Gap Analysis Program "gap" ranks, which measure the degree of conservation for biodiversity purposes. See the CPAD Manual for more information on gap ranks, which are as follows:

1 - managed for biodiversity –  disturbance events proceed or are mimicked;
2 - managed for biodiversity –  disturbance events suppressed;
3 - managed for multiple uses, subject to extractive (e.g. mining or logging) or OHV use;
4 - no known mandate for protection

Open Space Uses:    The lands in CPAD typically serve one or more of the following open space purposes:

  • Habitat Conservation - Wildlife or plant reserve protected specifically for habitat
  • Recreation – Active recreation, picnicking (city parks, parks with developed areas)
  • General Open Space – Open land used serving a broad range of purposes
  • Historical/Cultural - Historic sites, museums with large open areas
  • Forestry - Active forest harvesting, tree growth for forestry
  • Agriculture - Crop lands including developed pastures
  • Ranching - Grazing lands - dry and grazing pasture
  • Water Supply - Watersheds, waterways
  • Scenic area – usually part of other uses, however, sometimes called out
  • Flood Control – Flood plains, natural flood control channels (but generally not concrete or other impervious structures unless incidental to the overall holding)

Open Space vs. Hardscape:   Open space holdings in CPAD may include buildings or other hardscape areas, provided the hardscape is subordinate or ancillary to the dominant open space purposes of the holding. As a general rule, the holding is not considered open space if structures or other hardscape constitutes a large portion of the total acreage (roughly half or more, based on visual inspection). 

  • Parking lots used principally for qualifying public recreational purposes are considered part of the protected open space holding. In smaller urban parks, parking lots may not be included due to difficulties in determining their relationship to park holdings and  resource limitations for fact-checking.
  • Recreation facilities that are primarily buildings (e.g. indoor ball courts, swim centers, community centers, stadiums without significant open space areas around them) are not included in CPAD. 
  • City parks:  City parks in CPAD often exclude major building areas from remaining open space, due to lack of consistent and detailed information on which buildings are parts of parks. In general, parks with more than half their area in building structures are not included in CPAD.

 Additional Open Space Criteria

  • Schools.  Park-like areas that are parts of public schools are not included in CPAD unless there is a known, defined agreement to allow those for public use (often called “joint use agreements”). CPAD may include some school park sites without such agreements – if you find these errors, please contact us at: or use the CPAD MapCollaborator application to report them.
  • Cemeteries.  Privately-owned cemeteries are not considered protected open space, but cemeteries owned by the public are considered open space – and are given a special flag in the database attribute table.
  • Golf courses.  Privately-owned golf courses are not included in CPAD, but golf courses owned by the public are and are given a special flag in the database attribute table. Golf courses owned by homeowners associations are considered privately owned and are not included in CPAD.
  • RV parks.  Publicly owned RV parks and similar highly-developed camping or lodging facilities are not generally included in CPAD; however, if they are a subordinate part of a larger protected open space area and are themselves protected through fee ownership, they may qualify (e.g., if a state park has camping areas for RVs, those areas are included).
  • BLM offshore islands that make up the California Coastal National Monument are included in CPAD and given a special flag in the database attribute table.
  • Open land holdings of transportation agencies (highway medians, construction staging areas, etc.) are not included in CPAD. (Note: in the future, such open space could be considered protected if significant enough in size and configuration, and permanently protected in such use through joint-agency agreements or easements). However, "remnant" parcels of open land whose location or configuration significantly impair any broader open space purpose (e.g., highway or roadway shoulders or medians) are generally not included in CPAD.
  • If a non-open space use occupies a portion of a larger open space area, and it is a separate parcel and functions separately from the larger open space area, then it is usually excluded from CPAD. However, if it is not a separate parcel, and/or it is difficult to separate from the larger open space area, then the entire area is included in CPAD.
  • Holdings of water/flood control agencies that do not serve open space purposes are not generally included – for example, concrete flood channels and developed access ways along such channels or other open lands that only support the use of constructed facilities, unless those facilities are a small portion of an overall open space holding owned by such an agency (e.g., dams that are part of recreation areas). However, trail corridors along such channels and water detention basins are often included.

Other Ownerships:   CPAD includes protected areas owned in fee by public agencies and non-profits, plus some homeowner associations (see below).  Military and Tribal lands are not included in CPAD:

  • Military Lands.  CPAD does not include Defense Department lands, except for a few public recreation facilities (e.g. golf courses) and some Defense lands managed by the National Park Service.  GreenInfo Network has developed a provisional GIS layer of military lands available on the Cal-Atlas web site (download this 713kb zip shape file from the old Cal-Atlas site)
  • Tribal Lands.  Tribal lands are sovereign lands and are not included in CPAD unless subject to enforceable conservation restrictions.  GreenInfo Network has developed a provisional GIS layer of tribal lands available on the Cal-Atlas web site (download this 270kb zip shape file from the old Cal-Atlas site).

Home Owner Associations.  CPAD now includes some private park holdings owned by home owner associations (HOAs), mainly in Orange County. These lands are listed as ‘Restricted’ access since they are typically open only to the residents of the association. Only a few of California’s HOA parks are currently captured in CPAD. These parks are included since they provide important recreational opportunities even if restricted in use – without including them, any estimates of urban park needs could be misleading.

Ownership vs. Management:    CPAD tracks lands according to the agency that owns the title to the property. If another agency manages the site, both agencies are noted:  the owning agency is listed under ‘Owning Agency’ and the managing agency is listed under ‘Managing Agency’. CPAD listings by agency may therefore differ from similar listings by an individual agency, where that agency is showing both owned and managed sites.

Public Access:   CPAD lands are defined as Open, Restricted, or Closed. Restricted areas require permits or have irregular hours. Closed areas are not open to the public. Any map of recreational opportunities must not include Closed areas and should indicate that any Restricted lands require a permit or a check-in before visiting. 

Land and Water:  Water areas of protected fee land holdings (tidal areas, coastal areas, lakes/reservoirs) are included for most of the state and identified with a “water” code. Water boundaries are taken from a variety of sources including 100K DLG and the National Hydrology Dataset (NHD), and in some cases manually drawing the water boundary using aerial imagery.  Some revisions have been made for Bay Area tidal zones. CPAD does not show creeks, streams, or very small water bodies (i.e., small lakes, ponds under 10 acres). The water/land attribute is only in the HOLDINGS feature class (see list below).


The key framework of the CPAD database is the division of open space lands into the feature elements described below. CPAD is maintained as a PostGIS database and releases are published as a set of three shapefiles, to provide easy data access for the greatest array of users:

CPAD structure image



Map of CPAD data