Please note: In many cases, the station position in our database is accurate
to only one minute. Thus, the tide gauge may not appear to be on the coast.
Portsmouth 170/131 RLR(1971) is 10.2m below BM SU6270 0053
Documentation added 1992-05-05
Prior to 1991 data were received from UK Hydrographic Office
Documentation added 1994-07-21
Gauge details prior to 1960 are unclear. In 1960 a Lea stilling well gauge was installed, replaced in January 1991 by an "A Class" bubbler system.
Documentation added 1994-10-27
A letter to the Dock and Harbour Authority, No.61, page 385, 1981 by Webber and Walden castes doubts on the stability of the datum at Portsmouth during the 1960s and 1970s.
Documentation added 1997-07-16
Revised BM information for 1980-96
Documentation added 2001-01-02
Recent work on vertical land movements in the UK can be found from the University of Nottingham web site:http://ukcogr.iessg.nottingham.ac.uk/~eosi/
Documentation added 2012-05-24
Following re-leveling the Grid Reference for the Primary banchmark has changed from SU 6270 0053 to SU 6269 0053.
Documentation added 2014-07-04
There were no MSL's calculated for Portsmouth before August 2013 this was due to the fact that the primary channel, channel 2 was recording a constant -1.124m because of a leak on the system.
Documentation added 2015-05-18
TGI were at site 16.01.14 to carry out general maintenance and change the compressor.
Data Authority
British Oceanographic Data Centre National Oceanography Centre Joseph Proudman Building, 6 Brownlow Street Liverpool L3 5DA