Available NADCON Grids

 

 

Original Adjustment to NAD83(86)

 

Area

Description

Grid Pair File Prefix

 

 

 

CONUS

Conterminous 48 States:  NAD27 - NAD83(86)

conus

Hawaii

Hawaiian Islands:  Hawaii Datum - NAD83(86)

hawaii

Alaska

Alaska, including Aleutians:  NAD27 - NAD83(86)

alaska

St. George Is., AK

Alaska, St. George Island only:  Island Datum - NAD83(86) Alaska, St. George Island only

stgeorge

St. Lawrence Is., AK

Alaska, St. Lawrence Island only:  Island Datum - NAD83(86) Alaska, St. Lawrence Island only

stlrnc

St. Paul Is., AK

Alaska, St. Paul Island only:  Island Datum - NAD83(86)

stpaul

Puerto Rico and Virgin Islands

Puerto Rico and the American Virgin Islands:  Puerto Rico Datum - NAD83(86)

prvi

St. George Is. and St. Paul Is. are part of a region known as the Pribilof Islands. There were two separate datums, one for each Island, before NAD83(86). The old island datums differ significantly from NAD27.

The CONUS grids cover an area from 20 to 50 degrees north latitude and from 63 to 131 degrees west longitude. The Alaskan grids cover an area from 46 to 77 degrees north latitude and from 128 to 194 degrees west longitude. The CONUS and Alaskan grids overlap between 46 to 50 degrees north latitude and 128 to 131 degrees west longitude. In this area, the CONUS and Alaskan grids agree within 2 centimeters. For those cases requiring precision greater than this, the CONUS grids are to be considered correct.

 

NAD83(86) to High Accuracy Reference Networks (HARN/HPGN)

 

Area

Description

Grid Pair File Prefix

 

 

 

Alabama

Alabama HARN:  NAD83(86) - NAD83(92)

alhpgn

Arkansas

Arkansas HARN:  NAD83(86) - NAD83(97)

arhpgn

Arizona

Arizona HARN:  NAD83(86) - NAD83(92)

azhpgn

California

California HARN, 37 degrees latitude and above:  NAD83(86) - NAD83(92)

cnhpgn

California

California HARN, 37 degrees latitude and below:  NAD83(86) - NAD83(92)

cshpgn

Colorado

Colorado HARN:  NAD83(86) - NAD83(92)

cohpgn

Florida

Florida HARN:  NAD83(86) - NAD83(90)

flhpgn

Georgia

Georgia HARN:  NAD83(86) - NAD83(94)

gahpgn

Hawaii

Hawaii HARN:  NAD83(86) - NAD83(93)

hihpgn

Idaho - Montana

Idaho and Montana HARN, 113 degrees longitude and east:  NAD83(86) - NAD83(92)

emhpgn

Idaho - Montana

Idaho and Montana HARN, 113 degrees longitude and west:  NAD83(86) - NAD83(92)

wmhpgn

Iowa

Iowa HARN:  NAD83(86) - NAD83(96)

iahpgn

Illinois

Illinois HARN:  NAD83(86) - NAD83(97)

ilhpgn

Indiana

Indiana HARN:  NAD83(86) - NAD83(97)

inhpgn

Kansas

Kansas HARN:  NAD83(86) - NAD83(97)

kshpgn

Kentucky

Kentucky HARN:  NAD83(86) - NAD83(93)

kyhpgn

Louisiana

Louisiana HARN:  NAD83(86) - NAD83(92)

lahpgn

Maryland - Delaware

Maryland and Delaware HARN:  NAD83(86) - NAD83(91)

mdhpgn

Maine

Maine HARN:  NAD83(86) - NAD83(96)

mehpgn

Michigan

Michigan HARN:  NAD83(86) - NAD83(94)

*mihpgn

Minnesota

Minnesota HARN:  NAD83(86) - NAD83(96)

mnhpgn

Mississippi

Mississippi HARN:  NAD83(86) - NAD83(92)

mshpgn

Missouri

Missouri HARN:  NAD83(86) - NAD83(97)

mohpgn

Nebraska

Nebraska HARN:  NAD83(86) - NAD83(95)

nbhpgn

Nevada

Nevada HARN:  NAD83(86) - NAD83(94)

nvhpgn

New England

Connecticutt, Massachusetts, New Hampshire, Rhode Island, Vermont HARN:  NAD83(86) - NAD83(96)

nehpgn

New Jersey

New Jersey HARN:  NAD83(86) - NAD83(96)

njhpgn

New Mexico

New Mexico HARN:  NAD83(86) - NAD83(92)

nmhpgn

New York

New York HARN:  NAD83(86) - NAD83(96)

nyhpgn

North Carolina

North Carolina HARN:  NAD83(86) - NAD83(01)

nchpgn

North Dakota

North Dakota HARN:  NAD83(86) - NAD83(96)

ndhpgn

Ohio

Ohio HARN:  NAD83(86) - NAD83(95)

ohhpgn

Oklahoma

Oklahoma HARN:  NAD83(86) - NAD83(93)

okhpgn

Pennsylvania

Pennsylvania HARN:  NAD83(86) - NAD83(92)

pahpgn

Puerto Rico - Virgin Islands

Puerto Rico - Virgin Islands HARN:  NAD83(86) - NAD83(97)

pvhpgn

South Carolina

South Carolina HARN:  NAD83(86) - NAD83(01)

schpgn

South Dakota

South Dakota HARN:  NAD83(86) - NAD83(96)

sdhpgn

Tennessee

Tennessee HARN:  NAD83(86) - NAD83(95)

tnhpgn

Texas

Texas HARN, 100 degrees longitude and east:  NAD83(86) - NAD83(93)

ethpgn

Texas

Texas HARN, 100 degrees longitude and west:  NAD83(86) - NAD83(93)

wthpgn

Utah

Utah HARN:  NAD83(86) - NAD83(94)

uthpgn

Virginia

Virginia HARN:  NAD83(86) - NAD83(93)

vahpgn

Washington - Oregon

Washington - Oregan HARN:  NAD83(86) - NAD83(91)

wohpgn

West Virginia

West Virginia HARN:  NAD83(86) - NAD83(95)

tnhpgn

Wisconsin

Wisconsin HARN:  NAD83(86) - NAD83(95)

wihpgn

Wyoming

Wyoming HARN:  NAD83(86) - NAD83(93)

wyhpgn

* During the analysis of the transformation grids for Michigan, a serious inconsisitency was found in the positional shifts for the control on Isle Royale when compared with the mainland portion of the state. Investigation revealed that this was due to the fact that no HARN stations had been observed on the island, and that the existing horizontal control had poor geometric ties to the networks in Michigan and Minnesota. The island is classified as a wilderness area by the National Park Service and will see little if any development. Therefore, the data for this area was omitted in the development of the transformation grids.

 

 

Other

 

Area

Description

Grid Pair File Prefix

 

 

 

American Samoa

Ofu, Olosega, Ta'u Islands: American Samoa 1962 - NAD83(93)

**eshpgn

American Samoa

Tutuila, Aunu'u Islands: American Samoa 1962 - NAD83(93)

**wshpgn

Guam

Guam: Guam 1963 - NAD83(93)

guhpgn

** The positional data for American Samoa is distributed over two clusters of islands separated by many miles of ocean. The lack of control on which to base grids which this separation represents creates distortions unless the grids are split into two separate grid pairs.

Guam and American Samoa never went through the intermediate step of island datum to NAD83(86). Those islands were adjusted directly from their old island datums to HPGN/HARN.