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About Our Hydrographic Service


The Port of London Authority (PLA) has the busiest port hydrographic department in the UK with nine surveyors and support staff comprising 18 employees in total. The department has 3 dedicated survey craft fitted with multibeam echo sounder systems (MBES).

The PLA's Hydrographic Service is responsibile for surveying 400 sq. miles of the River Thames and estuary, from the tidal limit in the west out to the southern North Sea, some 95 miles. Surveys are primarily conducted for safety of navigation, but a significant effort goes into conservancy and environmental monitoring surveys, as well as detailed engineering works. In all over 400 surveys a year are made.

The Hydrographic Service also operates and maintains 14 remote tide gauges, feeding observations back in real time for re-transmission to vessels navigating the area.

The Port of London is the second largest UK port by tonnage, and caters for tens of thousands of vessel movements each year. The department has a key role to play in the management of the port including facilitating navigational safety, managing and protecting the environment, and promoting the use of the Thames through supporting terminal owners and operators.

The department has been heavily involved in the planning and support of on-going Thames-based projects particularly the Tideway Tunnel, Forth Ports' Tilbury 2 and DP World London Gateway Port development. The Hydrographic Service has undertaken wide area monitoring, dredge support and high resolution asset inspection and monitoring surveys. London Gateway Limited chose the PLA Hydrographic Service as their independent survey provider to undertake qualifying pre and post dredge surveys and to undertake all of the bathymetric monitoring surveys specified in the port development licence. Thames Water awarded their full river monitoring contract which the PLA utilised vessel based multibeam, vessel based laser and high resolution photography to survey bank to bank along 23kms of the river. In addition the department gives project support for major projects on the Tidal Thames and has worked under contract for National Bodies and educational institutions, including CEFAS, the Environmental Agency, the National Oceanographic Centre, British Geological Survey (BGS) undertaking bathymetry and geophysical and seabed sampling support work.

The department undertakes approximately 50% of it's work for third parties under contract, and it is accepted as a centre of excellence in the field of port surveying, and has recently gained a reputation for innovative use of high resolution multibeam in the support of infrastructure projects and ongoing inspection and maintenance and works closely with the UKHO and MCA on chart production and national interest mapping.

The PLA believes that technology is only as good as the professional acquiring and processing the data. The PLA have the highest calibre and experienced personnel available for project support.

Our clients include  – 

National Grid Grain – Survey support  for the terminal ranging from general bathymetric surveys through to the highest resolution multi sensor asset inspection surveys.

CEFAS – London Array Windfarm compensatory habitat area mapping : MBES

National Oceanographic Centre – Vessel and MBES to support geophysical survey of flooded river valley geology off SE Coast

Environment Agency – Thames Barrier, weir and river surveys on Thames and tributaries

Centrica – Rough field gas pipeline and offshore platform structural surveys

Orsted – Windfarm bathymetric wide area and turbine structural monitoring surveys.

Transport for London, Network Rail and Crossrail – Rail and road bridge and tunnel asset monitoring surveys.

Utilities providers (Eon/Uniper, RWE NPower , Thames, Anglain, Southern Water – high resolution intake and outfall surveys.

Tideway – Since 2019 have multiple facets of project support work including riverbed sampling, geophysical monitoring, geotechnical coring/CPT works and quarterly full river and site specific riverbed surveys.  In all cases works to date have been delivered to specification, on time and on budget.

Lower Thames Crossing – During 2018/19 undertaken design support surveys including riverbed monitoring, geophysical and geotechnical investigations including ultra-high resolution seismic (UHRS) investigations, UXO surveys, benthic and chemical soil sampling and analysis.

CGN – 2019, first marine contractor involved in the critical feasibility and design support works at the Bradwell B power station site undertaking baseline wide area bathymetry, UHRS seismic & 3D Chirp to support critical planning studies.

University College London and the PLA Hydrographic Service have formed a partnership to deliver a one year postgraduate MSc in Geospatial Sciences. The course has been awarded Category A accreditation by the International Hydrographic Organisation (IHO). For further information about this course see MSc in Geospatial Sciences

Vessels and equipment

Click on images below to see technical specifications




Hydro RIB



The department currently employs 8 surveyors, 3 office based and 5 field surveyors.  All field surveyors have at least a BSc and a minimum of 5 years survey experience in the industry and in general have over 10 years including offshore experience.

The department has a qualified Oceanographer as our Port Conservancy Manager and a GIS Manager and Assistant. The team have broad experience in the field of hydrographic data assessment, analysis, and charting.

Five of our field surveyors have attended the Ocean Mapping Group Multibeam Course run by the University of New Brunswick which is a recognised course of excellence in the industry delivered by renowned specialists.

The Department has five dedicated vessel crew members all of whom have extensive river and estuarine experience and who hold boat masters licences, local knowledge endorsements and in order to support our diverse  range of project work in the UK, we have a cohort of 4 qualified as MCA commercially endorsed offshore masters.

Final responsibility for all surveys or associated services rests with the Port Hydrographer, a with 25 years experience of surveying on the Thames and offshore..

The PLA in conjunction with University College London deliver an MSc in Hydrographic surveying which is accredited by the International Hydrographic organisation (IHO) to award a Category A Surveying Qualification.


Tel:- (+44) 01474 562207


Any general or safety of navigation queries should be directed to [email protected] or call 01474562207

All queries and administration associated with contracted services are co-ordinated by the commercial team email: [email protected]  .


Port of London Hydrographic Service,

London River House,

Royal Pier Road,

Gravesend, Kent, DA12 2BG.


Hydrographic Services Films

Watch the films about our hydrographic service:

Hydro Overview

Education and Survey Capabilities

Commercial Overview

Vessel Naming Ceremony (Thame)

Autonomous Surface Vessel ASV Trial

Unmanned Aerial Vehicle (UAV) Survey

National Grid Asset Inspection

Shell UK Jetty Case Study Asset


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