=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 07-Dec-1999
The Oyarvide gauge is on a tower and has a Leupold Stevens float gauge.
It is far from the coast (about 10 nautical miles) and does not have
benchmarks. It is not to be confused with another tower at
35 12 S 57 10 W which operated from 1966-1970 and had a gauge record
with many interruptions.