Legaspi 660/021 RLR(1964) is 9.1m below BM1 (1961). Gauge type = Ott, (30th March 1999).BM1 (1961) disturbed October 1983, but datum of data unchanged.BM2 (1989) disturbed when pier repaired in 1994, but the datum of the data has remained unchanged.
Documentation added 2010-10-14
There has been a number of changes to the datum value over the years as different levelling excercises have taken place.1947-1984 BM 1 3.675m above TSO 1947 1985-88 BM 1 3.702m above TSO 1947 see letter dated 22.01.1988 1989-1997 BM 2 3.818m above TSO 1947 1998-9 BM 2 3.790m above TSO 1947 2000-2002 BM 2 4.009m above TSO 1947 2003 benchmark name becomes B 22 2005-7 value rounded to 4.01m 2008 back to 4.009m Gauge type is THALIMEDES/SUTRON Different values were not included on the RLR diagram as the RLR factor does not change
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