=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 23-Mar-1994
data up to 1992 revised, March 1994
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 15-Jul-1994
Champlain           970/080 RLR(1975) is 12.1m below BM MMMCXXX
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 04-Apr-2012
Last data received for Champlain was that for 1994.