Readme.1976_1999

Oct. 29, 1999

The following files, included in the 1976_1999 workspace, are ARCINFO point coverages of Corps of Engineers hydrographic survey data located within the Southwest Washington Coastal Erosion Study (SWWCES) study area.  Data were obtained from Eric Nelson of the Seattle District Corps of Engineers and H. Rod Moritz, Portland District Corps.

For more information contact:
Ann Gibbs, US Geological Survey, 345 Middlefield Rd. MS 999, Menlo Park, CA 94025. agibbs@usgs.gov. Phone: 650-329-5060

***************************

Vertical datum: MLLW meters
Horizontal datum:  NAD83
Reference Ellipsoid: GRS80
Projection:  Washington Stateplane South, Zone 5626, meters

Coverages contain the following items:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME     INDEXED?
    1  AREA                   4    12     F      3                        -
    5  PERIMETER              4    12     F      3                        -
    9  H4612_1926#            4     5     B      -                        -
   13  H4612_1926-ID          4     5     B      -                        -
   17  DEPTH-MLLW             4     9     F      2                        -
   21  CARTOCODE              3     3     I      -                        -
   24  SURVEY                 7     7     C      -                        -
   31  SURVEY-YEAR            4     4     I      -                        -
   35  X-COORD                4    12     F      3                        -
   39  Y-COORD                4    12     F      3                        -

*****************************
The following is a summary of the data sets and edits applied to the data where indicated:

gh76anp = only contours; no edits
gh95anp = no edits
gh98anp = apparent problems with tracklines.  There are six overlapping tracklines in this survey.  Tracklines run east to west are coded 701-706.  Tracklines run west to east are coded 881-887.  Keep everything coded less than or equal to 711.

pcoe98pts = Two northernmost lines coded 999.  Soundings on the northernmost line are apparently ~1m too deep; soundings on line 2nd from the north are ~2.5m too deep.

pcoe99pts = no edits

w98_thinned = willapa98 data thinned in areas where SHOALS survey was apparenlty conducted (dense data coverage).

willapa99 = piecoe1 and wb99c appended coverages

ap81fa = Columbia River approach survey; fall 1981
ap83su = Columbia River approach survey; summer 1983
ap84su = Columbia River approach survey; summer 1984
ap85su = Columbia River approach survey; summer 1985
ap86su = Columbia River approach survey; summer 1986
ap88fa = Columbia River approach survey; fall 1988
ap92fa = Columbia River approach survey; fall 1992
ap94fa = Columbia River approach survey; fall 1994
ap97su = Columbia River approach survey; summer 1997
ap98su = Columbia River approach survey; summer 1998


COMPILED DATA COVERAGES:
nenc9xpts_v1: w98_thinned, pcoe98pts, pcoe99pts, gh98anp; no edit, no coast.
enc9xpts_v1:  selected out non-711 points in above coverages.