- The Coastline of the United States U.S DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration The Coastline of the United States Describing man's present and future physical environment is central to the work of NOAA, the National Oceanic and Atmospheric Administration. Much of this description is displayed in the cartographic products of NOAA's National Ocean Survey. Surveyed, resurveyed, and refined over the past century and a half, Na- tional Ocean Survey nautical and aero- nautical charts in a variety of forms are essential to safe, efficient navigation of the air and ocean. Bathymetric maps, a more recent development, are detailing the rich continental shelf lands of the United States. This pamphlet is still an- other part of that larger description. GENERAL COASTLINE figures are lengths of general outline of the seacoast. Measure- ments were made with a unit measure of 30 minutes of latitude on charts as near the scale of 1:1,200,000 as possible. Coastline of sounds and bays is included to a point where they narrow to width of unit measure, and the dis- tance across at such point is included. Most of the general coastline figures are the same as those published in the First (1915) Edition, but all were remeasured in 1948. The coast- line of Alaska was again remeasured in 1961, and again the 6,640-mile figure of 1915 was retained. The principal change in the 1961 edition is the increase of Florida coastline from 1,197 to 1,350 miles; this was checked and re-checked and reflects a new approach to measurement of the Florida Keys. TIDAL SHORELINE figures were measured in 1939-40 with a recording instrument on the largest-scale charts and maps then avail- able. Shoreline of outer coast, offshore islands, sounds, bays, rivers, and creeks is included to the head of tidewater or to a point where tidal waters narrow to a width of 100 feet. General Tidal Coastline* Shoreline* UNITED STATES 12,383 88,633 Conterminous only 4,993 53,677 Atlantic 2,069 28,673 Maine 228 3,478 New Hampshire 13 131 Massachusetts 192 1,519 Rhode Island 40 384 Connecticut 618 New York 127 1,850 New Jersey 130 1,792 Pennsylvania 89 Delaware 28 381 Maryland 31 3,190 Virginia 112 3,315 North Carolina 301 3,375 South Carolina 187 2,876 Georgia 100 2,344 Florida (Atlantic only) 580 3,331 Florida (Atlantic and Gulf) 1,350 8,426 Gulf of Mexico 1,631 17,141 Florida (Gulf only) 770 5,095 Alabama 53 607 Mississippi 44 359 Louisiana 397 7,721 Texas 367 3,359 Pacific 7,623 40,298 California 840 3,427 Oregon 296 1,410 Washington 157 3,026 Hawaii 750 1,052 Alaska (Pacific only) 5,580 31,383 Alaska (Pacific and Arctic) 6,640 33,904 Alaska (Arctic only) 1,060 2,521 EXTRATERRITORIAL Canal Zone 20 126 Atlantic Navassa 5 5 Puerto Rico 311 700 Swan Islands 8 10 Virgin Islands 117 175 Pacific Baker Island 3 3 Guam Islands 78 110 Howland Island 4 4 Jarvis Island 5 5 Johnston Island 5 5 Midway Island 20 33 Palmyra Island 9 16 Samoa Islands 76 126 Wake Island 12 20 ^Statute miles. ^ CANADA Lake Superior ^^ K^ _ Lake Huron Lake M Michigan ^^k W 3 Lake d fgj^r Ontario UNITED STATES ^ ^^^^Lake Erie Lengths of Great Lakes Shorelines and Con- necting Rivers, Including Islands" These shoreline lengths were measured in 1970 by the International Coordinating Com- mittee on Great Lakes Basic Hydraulic and Hydrologic Data. A precision instrument called a Map and Plan Measure, designed especially to determine the lengths of broken or irregular lines, was used on topographic maps and navi- gation charts. The scale of the maps was mainly 1 : 50,000 with a few larger scale maps. The scale of the charts varied from 1:30,000 to 1:120,000. Shoreline United States Canada Lake Superior 1250 1480 St. Marys River 120 130 Lake Michigan 1640 Lake Huron 840 2990 St. Clair River 30 40 Lake St. Clair 140 110 Detroit River 70 60 Lake Erie 470 400 Niagara River 70 40 Lake Ontario 330 380 St. Lawrence River above Iroquois Dam 220 260 above Power Dam 320 140 *AII numbers are rounded to nearest 10 miles. For sale by the Superintendent of Documents U.S. Government Printing Office Washington, D.C. 20402 Price 25 cents Stock Number 003-021-00002-5 Catalog Number C55.21C63 -frGPO:1975 O-574-303 NOAA/PA 71046 (Rev. 1975)