Monument MPM1387 - Water tanks, Portsmouth Grammar School

Two brick built ‘bee-hive’ water tanks c. Mid-19th century. Possibly part of a fresh water supply system for Cambridge Barracks. Recorded during an archaeological watching brief in 2013.

Two brick built ‘bee-hive’ water tanks were revealed during an archaeological watching brief on ground works for a new building at Portsmouth Grammar School in 2013. The tanks were 330mm thick and measured c.4m in diameter. The top of the dome was situated c.180m below ground level, and the chambers measured c.4.450 meters? from top to base. The tanks appeared to be linked by a north-south aligned connecting pipe, and they were found to contained fresh water. The location of the tanks corresponds with those recorded on an 1861 Ordnance Survey site plan. It is thought that they formed part of a fresh water supply system which served Cambridge Barracks.

The tanks were retained in situ on the site.

Accession number: 2013/745

Hall, N & Pine, C, A, 2014, Summary Report on the Results of a Watching Brief undertaken at Portsmouth Grammar School High Street Portsmouth (Unpublished document). SPM254.