OceanWise to maintain and upgrade the UK’s National Tide Gauge Network
The Environment Agency (EA) has awarded the prestigious UK ‘National Tide Gauge Network’ (NTGN) maintenance contract to OceanWise who, alongside RS Divers, have proudly taken over delivery of this important project. The NTGN owned by the EA on behalf of the UK Centre for Flood Forecasting (UKCFF) and comprises 42 ‘Class A’ tide gauge sites strategically located throughout the UK (see image). The contract will reinstate the network to its original specification, add new sensors and upgrade the data collection system to modern standards.
The bulk of the current NTGN was designed and originally installed by the Tide Gauge Inspectorate in the early 1990s, with each site consisting of two full tide and one mid tide ‘bubbler’ type gauges, supplemented at a few sites by underwater pressure gauges and/or downward looking radars. There are three sites also equipped with float type gauges that were adapted to provide a digital output, including one at Newlyn, the data from which was used to establish Great Britain’s orthometric height datum, Ordnance Datum (Newlyn), between 1915 and 1921.
Many of the ‘bubbler’ gauges fall short of their original specification due to wear and tear, or missing or non-standard components being fitted over the years, but are nonetheless serviceable and provide excellent continuity. The aim of the current contract is to reinstate the bubblers, thus improving their accuracy and reliability, and to establish a water level radar at each site for additional redundancy and to compare the radar data with the bubbler and float gauge datasets.
Dr Mike Osborne, OceanWise’s Managing Director explains, “We are delighted to have been given the responsibility of maintaining the NTGN on behalf of the nation. We already support and maintain numerous mission critical tide gauges for our port customers, so this contract is a natural extension of our work. We are particularly looking forward to working with the EA and National Oceanography Centre to upgrade the network, using our expertise and experience in new sensor and data acquisition and management technologies, whilst at the same time maintaining and enhancing the legacy ‘bubbler’ based systems.”
The purpose of the NTGN is to observe sea level throughout the UK in near real-time, as input to monitoring and forecasting coastal surge, and to provide a long-term and strategic record for climatological and coastal engineering studies. The predicted frequency and intensity of storms and coastal surges, coupled with sea level rise, due to climate change means that the collection and dissemination of accurate and reliable sea level data has never been more important. The data provided by the network of gauges is also used by academics and researchers for a variety of other scientific purposes. Several of the gauges are part of the Global Sea Level Observing System (GLOSS) and are of international and historical significance, with some datasets dating back to the 18th century.