Services
Hydrographic & Bathymetric Surveys
Sonar profiling of riverbeds, wet wells and surcharged assets.
Need a Specialist Hydrographic Survey?
Rivers, canals, reservoirs, and coastal zones are dynamic environments where the unseen underwater landscape is constantly changing. Trenchix provides Tier 1 hydrographic and bathymetric surveys, delivering a high-resolution, 3D “Digital Twin” of the riverbed or seabed.
We empower asset managers to see below the waterline, identifying critical risks such as bridge scour, siltation, and structural erosion without the need for dangerous diving operations.
We deploy a range of advanced acoustic technologies from dedicated survey vessels or Unmanned Surface Vessels (USVs), selected based on your site’s specific depth and access requirements.
Bathymetric Surveys (Multibeam & Singlebeam): The core of our offering is precision bathymetric mapping. We map the topography of the underwater terrain to centimetre-level accuracy.
Multibeam Echosounder (MBES): Captures a dense “point cloud” of the entire riverbed, revealing subtle features, scour holes, and bedforms in 3D.
What you get
- PAS 128 quality-level classification
- Layered DWG / GIS deliverables
- Georeferenced survey data
- Combined utility and topographical plans
- Designer-ready handover
Why Trenchix
Delivered with certainty
PAS 128 rigour
Survey methodology aligned to PAS 128, giving quality levels you can present to designers and clients.
CAD & GIS deliverables
Clean, layered deliverables that drop straight into your design environment.
Reduced strike risk
Know what is beneath the site before excavation — protect people, programme and budget.
How it works
From enquiry to evidence
Desk study
We review statutory records, existing drawings and site constraints to plan the most efficient survey methodology.
Site capture
EML, GPR and topographical instruments capture the site in one coordinated mobilisation, minimising disruption.
Process & verify
Data is processed, quality-levelled to PAS 128 and verified against records, with intrusive verification where required.
CAD delivery
Layered, georeferenced DWG and GIS deliverables are issued, ready to drop straight into your design environment.
Who it’s for
Built for commercial decision-makers
Designers & engineers
PAS 128 quality levels and CAD/GIS deliverables ready for design environments.
Main Contractors
Strike-risk reduction before excavation on live commercial programmes.
Local authorities
Utility and topographical data for highways and public realm schemes.
Why contractors trust Trenchix
FAQs
Frequently asked questions
What is PAS 128 and why does it matter?
PAS 128 is the UK specification for underground utility detection and verification. It assigns quality levels to every located utility, so designers know exactly how much confidence to place in the data — reducing redesign and strike risk.
What formats do you deliver in?
Layered AutoCAD DWG as standard, plus PDF and GIS-ready formats on request. Deliverables are georeferenced and drop straight into your design environment.
What accuracy can we expect?
Topographical surveys are delivered to survey-grade accuracy using total stations and GNSS. Utility mapping accuracy is stated per PAS 128 quality level, with intrusive verification available where certainty is critical.
Do you combine utility and topographical surveys?
Yes — combining both in one mobilisation is usually the most cost-effective approach and gives your designers a single, coordinated deliverable.
Can you work overnight or under possession?
Yes. Night working, weekend programmes and rail possessions are routine for our mapping teams where live operations require it.
Do you provide as-built updates after construction?
We can return to capture as-built utility positions post-construction so your records stay accurate for future works and maintenance.
Related services
Get In Touch
Ready to discuss your project?
From major infrastructure surveys to emergency commercial drainage callouts — our teams are available 24/7.