The sea level difference either side of the Panama Canal is approx. 20 cm (higher on the Pacific side) - see for example, Pugh, D.T. 1987, "Tides, surges and mean sea-level", Wiley. RLR 1964 datum at Balboa is 3.112 m below the "Tide Staff Zero" which is itself 12 feet below Panama Canal Precise Level Datum (PLD). On the Atlantic side, at Coco Solo RLR 1993 is 6.288 m below the Tide Staff Zero which is itself 2 feet below PLD there. For the older Cristobal data, RLR 1964 is 6.138 m below the Tide Staff Zero which is itself 2 feet below PLD. From inspection of RLR data and from this information, one can indeed verify that sea level is higher on the Pacific side by about 20 cm. However, the accuracy of the PLD national levelling system is unclear.
Documentation added 1998-10-07
data for January 1996-January 1998 received via WOCE databank (Hawaii) and has had preliminary quality control processing only
Documentation added 1999-05-26
The Naos station has apparently terminated operations.
Documentation added 2012-01-26
Apart from the benchmark name the figures on this RLR diagram are the same as Naos Island id. 581.As with the Naos Island data this station is no longer in operation last data is 1995.No further information is available on the NOAA website. Once again station has been marked 'inactive'.