=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 08-Jul-1993
Grand Isle                940/021 RLR(1978) is 8.0m below BM 6
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 29-Jul-1993
Many stations on the Gulf coast have large values for September 1961.
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 14-Jul-1994
For a discussion of submergence near to Eugene Island and Grand Isle/Bayou Rigaud, see Emery and Aubrey (Sea Levels, Land Levels and Tide Gauges), 1991, Springer-Verlag, page 40.