=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-Jun-1991 St Petersburg 940/061 RLR(1964) is 8.4m below BM4 =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 29-Jul-1993 Many stations on the Gulf coast have large values for September 1961. =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 23-Nov-2011 Using information from the NOAA website the RLR diagram has been revised. Previous Primary benchmark BM 4 2.667m above the gauge datum no longer appears on the NOAA report. Current Primary benchmark 6520 D 1991 is 2.850m above gauge datum.