Confluence Retirement

Due to the feedback from stakeholders and our commitment to not adversely impact USGS science activities that Confluence supports, we are extending the migration deadline to January 2023.

In an effort to consolidate USGS hosted Wikis, myUSGS’ Confluence service is targeted for retirement. The official USGS Wiki and collaboration space is now SharePoint. Please migrate existing spaces and content to the SharePoint platform and remove it from Confluence at your earliest convenience. If you need any additional information or have any concerns about this change, please contact Thank you for your prompt attention to this matter.
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Comment: Updating definitions


titleAmbulance Services

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titleThe Guidelines define Ambulance Services as follows:

A building used to house ambulances and from which medically-trained staff are dispatched to transport emergency patients and administer emergency medical treatment (en route or at the scene).

INCLUDES: Air ambulanceambulances, ground ambulanceambulances, ambulances not operated by fire departments but co-housed at a fire station, rescue vehicles not associated with fire departments.

DOES NOT INCLUDE: Ambulance services operated by and housed in a fire station, ambulances for transportation only (not providing medical care), special needs transports, ambulances operated by hospitals/medical centers, ambulance dispatch centers, urgent care centers, freestanding emergency facilities.

What is an Ambulance Service? 
An ambulance service facility is a building that houses a service houses vehicles and personnel to transport emergency patients and administer emergency medical treatment treatment but does not include ambulances operated by fire departments .
It is common for or hospitals.

If an ambulance is located in a fire station and is operated by fire department personnel, it is considered part of the fire department and not a separate ambulance service for our purposes. However, it is not uncommon for contract, private or non-profit ambulance services to operate out of fire department stations

and to be considered as part of the fire department operations -- these facilities are not included as ambulance service facilities (only as Fire Department facilities); generally you can refer to the fire department website to determine the relationship between the two entities. However,

through a government contract or mutual aid agreement. (The fire department’s website usually specifies the relationship between the two entities.) These facilities, which are not operated by the fire department personnel, meet the criteria for ambulance collection.

Both for-profit and non-profit ambulance services may also operate out of their own facilities seperate separate from fire departments -- these and are included as ambulance service facilities.For-profit ambulance services generally have their own facilities, which should be captured as ambulance service structure points

Do we include air ambulance (helicopters and fixed-wing aircraft) locations as Ambulance Service locations? 
Air ambulances are included as ambulance service locations; however it may be difficult to determine where helicopters and fixed-wing aircraft are stationed. Most hospitals have helipads, but these are not home stations for air ambulances. The home stations for air ambulances generally are at airports. State health departments or state emergency management divisions may maintain lists of air ambulance services licensed to operate within their state.

Where can I find authoritative lists of Ambulance Services? 
Refer to the State Data Sources pages on this website for state and local lists of ambulance services. Ambulance services generally are Ambulance services generally are licensed by counties or by state, so you may find lists at county information listed on government websites. State Health Departments health departments or state emergency management divisions may also may maintain lists of Ambulance Services.
Do we include air ambulance (helicopters and fixed-wing aircraft) locations as Ambulance Service locations? 
Air ambulances are included as Ambulance Service locations; however it may be difficult to determine where helicopters and fixed-wing aircraft are stationed. Most hospitals have helipads, but these are not home stations for air ambulances. The home stations for air ambulances generally are at airports. State Health Departments may maintain lists of air ambulance services operated within their State.ambulance services.

Check out our Authoritative Sources List for more on the types of sources that are acceptable.
Where do I place an Ambulance Services structure point?
Most ambulance services structures have one building. If this is the case, place the point at the center of the building. If the structure operates out of the same building as a Fire Department and/or Law Enforcement facility, distribute the points on the building so that they are not overlapping.

Stations can generally be recognized in Aerial Imagery or in Google Street View™ because the stations have large bays with overhead doors and large concrete pads outside where the ambulances can park.

For more information on how to identify an ambulance services structure, check out the “Aerial Photo Interpretation Part 6: Ambulance Services” article in our July 2018 Newsletter


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titleThe Guidelines define Cemetery as follows:

A place or area for burying the dead.

  • INDICATORS: Interments.

INCLUDES: Burial grounds, graves, graveyards, memorial gardens, mausoleums, columbariums, and crypts.

DOES NOT INCLUDE: Graves inundated by lakes or reservoirs, historic cemeteries, unnamed cemeteries and/or graves, funeral homes.

What is a Cemetery? 

The Guidelines definition of a cemetery is straightforward -- it includes places where the dead are buried. The human dead anyway -- pet cemeteries are not included. It addition to the types of features mentioned in the Guidelines, columbariums (a place for the storage of urns containing cremated remains) are also included.

Some small family cemeteries (usually historical) are included in the database, but in general more recent family cemeteries are not included. Single graves also are generally not included, unless they are the graves of famous historical figures.
Where does our Cemetery database originate?

There are two principal sources of cemetery data in the TNMC Structures database: US Geological Survey Topographic maps, and the USGenWeb project.

US Geological Survey topographic maps were produced from about 1879 to 1992 using a combination of aerial photographs and on-the-ground surveys and inventories. In addition to large more-modern cemeteries, many small cemeteries of historical significance were mapped, and these are included in our database. If you are viewing a listed cemetery location in the Aerial Imagery view of the Potlatch editor, and there doesn't seem to be anything visible there, try switching over from aerial imagery to USGS Topos, and then you often will see the notation of a cemetery on the topographic map.

Additional cemetery locations were submitted to the database by the USGenWeb Project. This volunteer project, started in 1996, fosters Internet resources for genealogical research in every county and every state of the United States.

Because many historical cemeteries have been carefully documented and included in the database, please do not remove cemeteries from the database simply because they are not visible in aerial imagery. Only remove cemeteries if the imagery shows without a doubt that the landscape has been altered (for example, a shopping center now exists where the cemetery used to be), or if you have local or on-the-ground knowledge that the cemetery has been moved or destroyed.

Where should I place a cemetery structure point?

The general rule is to locate the cemetery structure point at the centroid of the cemetery area. A single point should be placed even if a cemetery has a combination of facilities (graves, mauseleums, columbariums).

Some columbarium-only facilities are located in church buildings, although their presence may be difficult to ascertain or validate; they should be represented by a point at the center of the church structure.

What are authoritative sources of information about cemetery locations?

There are no single complete authoritative sources of information about cemeteries, but there are many internet resources that together can provide a fairly complete list of cemeteries:
  • The Find A Grave website has a quite comprehensive list; you can search for cemeteries by name or county. The website gives latitude and longitude for most cemeteries.
  • The has a smaller list which can be searched by county.
  • The BillionGraves website has coordinates for cemeteries in its database, and shows the location of the cemetery on aerial imagery. You can search their database by county.
  • The USGenWeb Project archives list cemeteries by State and County. It also has cemetery lists as part of its Tombstone Transcription Project.
  • The Churches and Cemeteries website lists cemeteries by State and County.
  • Check the Data Sources page for your State on this website -- there may be local resources with cemetery locations.

What Address should be given for rural cemeteries?

Many cemeteries are located in rural areas where county and state roads do not have precise mailing addresses. You can attempt to find an address through reverse geocoding in Google Maps™ Classic: 
  1. Locate the cemetery on Google Maps™ Classic.
  2. Right-click on the road at the cemetery entrance and select "What's Here?"
  3. In the search box, Google Maps™ will show the latitude/longitude of the point where you clicked.
  4. In the left pane of the map window, Google™ will show the best mailing address it could come up with using its reverse-geocoding service. If it cannot come up with an address, it still will show the name of the nearest street, and the city and zipcode of the location.
In cases where no numbered street address seems to be assigned:
  1. If there is a road intersection nearby, put in the road names, for example, "County Road 10 and US Highway 20".
  2. If there is only a single road nearby, use only the name of the nearest road, for example, "County Road 10".
  3. If no road is nearby, leave the Address blank, and fill in only the nearest city (and zipcode, if you know it).

Why do we collect information about cemeteries?

Perhaps the original reason we started collecting information about cemeteries is that they were prominent feature types shown on USGS topographic maps. But another reason is that there are many people that are interested in history and genealogy and find this information useful. One of our volunteers says:

" a lifelong genealogist, I have been frustrated with the gap between local information about cemeteries and what is easily available in a consistent, reliable, national format. I have benefited from hundreds of thousands of hours of work by others and this is the way I am giving back."