1926-68 DATA FROM PORTSMOUTH (NAVY YARD) SITE
1969-1972 DATA FROM SEAVEY IS, BACK CHANNEL SITE
1973 TO DATE DATA FROM SEAVEY IS,BERTH 2 SITE
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-Jun-1991
Seavey Island       960/177 RLR(1972) is 12.9m below BM12
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 12-Jul-1993
Seavey Island       960/177 RLR(1972) is 12.9m below BM12
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 15-Feb-2012
Seavey Island is now an Historic station. Last data received was that for 1986.
Information from the NOAA website confirms Primary benchmark to be NO 21 1975
$.59m above TGZ. Benchmark 12 from the original RLR diagram no longer features
on the NOAA website.