Implementation of Lidar into UKHO Survey ContractsAuthors: Robert Andrew, David Parker

The Hydrographic Society UK, SW Region

& Shallow Survey 2018

Aims of this Presentation

• UKHO history with Lidar surveys

• UKHO Current Survey Programmes

• UKHO current requirements and use of Lidar data

• Data comparison between MBES and Lidar

• Successes

• Challenges

• Conclusions

UKHO History with Lidar Surveys

UKHO have always been keen to make suitable use of lidar where it

provides value for money.

However, UKHO were never convinced by early claims (~2002) of

data meeting IHO Order 1 / 1A requirements.

• MCA / UKHO Trials 2003

• UK Civil Hydrography Programme lidar survey in Scotland 2004

• Chaired IHO working group – Order 1B in 2008

Lidar Trials 2003

MCA and UKHO trial to test feasibility of using lidar and potentially achieving Order 1 requirements.

Plymouth UK – -50 to 25m depth achieved.

2m cube deployed in 18m of water

Cube not detected and least depth not found.

Sound of Harris – UK Civil Hydrography Programme 2004

Validation showed useable data down to ~25m.

Allowed new route for ferry to be selected.

Further multibeam survey showed many small features not detected.

Sound of Harris - 2004

UKHO Chair S44 Working Group

Ambition to create new standard to

allow procurement, use and realistic

description of lidar data.

Order 1B created in 2008 (S-44 v5)

Requirement for 5 x 5m grid – but no

object detection requirement.

UK Chair – Chris Howlett

2016 – International Programmes

• UKHO have funding approved for Commonwealth Marine

Economies Programme and UK Overseas Territories

Programme.

• Requirement to collect hydrographic data for 31 island or coastal

states.

• Acoustic surveys for all areas required would be unaffordable

and take decades to achieve.

• In many cases, lidar would provide the best value for money.

www.gov.uk/guidance/commonwealth-marine-economies-

programme

Commonwealth MarineEconomies ProgrammeEnabling safe and sustainable marine economies across Commonwealth Small Island Developing States

www.gov.uk/guidance/commonwealth-marine-economies-

programme

Secure Future –Seabed Mapping17 April 2018

www.gov.uk/guidance/commonwealth-marine-economies-

programme

CME Activities Across 17 Commonwealth States

Benefits of seabed mapping:

• Safer and more efficient ship navigation

− so bigger and more ships can visit – carrying more goods and passengers

− supporting the development of marine economy, international trade and tourism

− preserving the environment, marine life and resources by reducing risk of maritime incidents

• Better planning and management

− mitigation of climate change, tsunamis, hurricanes, coastal erosion

− providing information for infrastructure development, like ports, jetties, breakwaters, hotels

− used as foundation for creation of marine habitat maps

− using the marine environment more effectively and sustainably

• Meeting their international obligations and commitments

10

www.gov.uk/guidance/commonwealth-marine-economies-

programme

11

Case study - Grenada

The waters in the approaches to the main port, St George’s, were not previously surveyed to modern standards

• In 2016, the cruise terminal handled

− over 200 ships

− over 314,000 passengers

− largest ship was 330 meters long with a draught of 8.3m and 4,300 passengers

− Cruise industry putting pressure on Grenada’s Government to improve charting

• In 2013, the commercial port handled

− over 437,000 tonnes of cargo

− largest ship was 183 meters long with a draught of 8.54m

www.gov.uk/guidance/commonwealth-marine-economies-

programme

12

Survey results

Pre 2018 chart New 2018 chart

Uncharted

shoal

Uncharted

wrecks

Uncharted

obstruction

Uncharted

wreck (7.7m)

www.gov.uk/guidance/commonwealth-marine-economies-

programme

13

Survey results

Seabed mapping identified hazards that could potentially affect shipping when compared to routes followed by ships into St George’s

A new chart has meant that:

• Safer access to ports

• Maximising draft of vessels, therefore efficiency

• Encouraging cruise industry access and growth

• Future development is based on up-to-date information

• Reduced risk of environmental disasters as hazards have been identified therefore:

– Protecting maritime resources

– Preserving marine life

www.gov.uk/guidance/commonwealth-marine-economies-

programme

Large ships have regularly passed close by dangerous wreck

Least depth over wreck = 7.7m

Jewel of the Seas Draught = 8.5m

www.gov.uk/guidance/commonwealth-marine-economies-

programme

CME Programme UKHO Activities

Overseas Territories Seabed Mapping Programme

A constituent part of the Sovereignty, Defence and International Obligations Programme

The main funding source is the Conflict, Stability and Security Fund (CSSF)

UKHO has been provided funding to assist OTs with ensuring safety of navigation within their waters through its OTs Seabed Mapping Programme which will last for four years (2016-20)

Key linkage with MCA’s work to prepare OTs for the IMO Instruments Implementation Code (IIIC) audits

Overseas Territories Seabed Mapping Programme

The Programme Objective is to reduce the risk (local and UK) of a serious maritime accident

Under the UKHO’s Seabed Mapping Programme we are:

•Assessing the national hydrography framework (legislation and Governance)

•Updating surveys and charting to ensure compliance with international obligations

Using new information collected to assist with maritime boundary delimitation.

As part of capacity building providing equipment and training to develop hydrographic governance and local survey capability.

OTSMP Programme UKHO Activities

Rob Andrew

International Hydrographic Programmes Officer

2016 Expectations and Specs for Lidar

• Up to 60m extinction depths

• Order 1A density down to around 10m

• 3 x 3 soundings per 2m bin required for Order 1A areas –

hopefully down to 10m depth.

• Minimum of 2 unique soundings per 2m bin for Order 1B

areas.

• But no empirical requirement to prove 1A object

detection.

• Part of the UK’s Commonwealth Marine Economies Programme

• Supporting SIDS to make best use of their maritime resources

• Approximately 5800km2 survey area, covering entirety of shallow waters

Grenada / Saint Vincent and the Grenadines – Lidar Survey

Saint Vincent and the Grenadines - LIDAR

Data acquisition to update nautical charts, facilitate trade

and sustainable infrastructure development, and inform

marine conservation by collecting environmental baseline

data.

Fugro Bathy Lidar System Configuration: 2016

• Used during HI 1530 (St. Vincent and Grenadines) and HI 1535 (Anguilla) projects

• To attain project specification of 2 points in every 2m2 bin (to full depth/Lidar extinction)

• General configuration comprised TWO Optech-Fugro SHOALS systems (nominal 6KHz

pulse rate) and ONE Riegl VQ-820-G topo-bathy system

SHOALS x 2

Laser Pulse Rate 3.0 kHz

Laser Type Pumped diode Nd:YAG

Operating Altitude 300 - 500 m

Laser Classification Frequency-doubled Green

(532 nm) and IR (1052 nm)

Laser Power 3.5 mJ pp

Scanning Mechanism Arc (section)

Receivers Shallow (GAPD), Deep

(PMT), IR and Raman

Integrated Inertial System Applanix POS AV 510 v6

Riegl VQ-820-G

Laser Pulse Rate Up to 520 kHz,

selectable

Laser Type Class 3B

Operating Altitude 400 - 600 m

Laser Classification Green (532 nm)

Laser Power 0.02 mJ pp

Scanning Mechanism Arc (section)

Receivers Green

Density

IHO Order 1b IHO Order 1a<2 Hits/bin

2+ Hits/bin

<9 Hits/bin

9+ Hits/bin

Object Detection

Shoals data examined with overlapping MBES:

• Good correlation in features 6m or greater.

• Some 4m features seen in lidar, but not all.

• None of the 2m features identified in the MBES were present in

the shoals lidar data.

• Very limited overlap of MBES with Riegl data – but object

detection appeared to meet Order 1A Standards

Belize 2017 – LIDAR and MBES Dataset

Acoustic data acquisition of Belize’s main ports and approaches.

Data to be used to update nautical charts of the region, and assist

Belize in meeting its international maritime obligations.

Although not in the scope, Fugro collected Lidar data to

experiment with their new RAMMS system, providing a direct

comparison to the collected MBES data.

Fugro Bathy Lidar System Configuration: 2017 to date

• General configuration comprised new Fugro RAMMS (Rapid Airborne Multibeam Mapping

System) and Riegl VQ-820-G topo-bathy system

RAMMS

Laser Rate 30 Hz @ 900+ obs/pulse

(27Kpps)

Laser Type Class 3B

Operating Altitude 300 - 500 m

Laser Classification Green (532 nm)

Laser Power < 1 mJ pp

Scanning Mechanism Fan Multibeam (no

scanner)

Receivers Green

Integrated Inertial Applanix POS AV 510 v6

Riegl VQ-820-G

Laser Rate Up to 520 kHz,

selectable

Laser Type Class 3B

Operating Altitude 400 - 600 m

Laser Classification Green (532 nm)

Laser Power 0.02 mJ pp

Scanning Mechanism Arc (section)

Receivers Green

Caveats

• Area was effectively used as a test by Fugro, and to support vessel operations.

• The test data was supplied to UKHO free of charge.

• Data was not collected to be the final deliverable, so may not have been optimised in this regard.

• Water clarity was far from optimal in some areas.

Density

IHO Order 1b IHO Order 1a<2 Hits/bin

2+ Hits/bin

<9 Hits/bin

9+ Hits/bin

Does Data Density = Object Detection?

12m Object

16-28.2406N, 088-22.0403W, 9m depth

Measurement LiDAR MBES

Least Depth 9.26 9.28

Height 2.20 2.25

Length 11.75 12.25

Width 7.25 7.75

Lidar MBES

8m Object

16-28.0993N, 088-21.8839W, 10m depth

Measurement LiDAR MBES

Least Depth 11.44 11.51

Height 2.50 2.45

Length 4.80 8.05

Width 2.10 6.10

Lidar MBES

6m Object

16-28.9040 N, 088-21.7516 W, 10m depth

Measurement LiDAR MBES

Least Depth 11.31 11.32

Height 2.50 2.50

Length 6.00 6.75

Width 4.75 6.5

Lidar MBES

Object detection of 4m and smaller objects…

• None of the <4m features identified in the MBES were present in the shoals lidar data in the area of the test.

MBES LIDAR

2m Objects

4m Objects

6m Objects

8m Objects

Despite big improvements in data density, there are significant issues of disproving depths and

features with lidar…

Chart deconfliction is tricky if we can’t trust that the Lidar data has detected all objects.

Charting Comparison Examples

Before and After….

(From SVG and Grenada)

HI1530 Lidar – Admiralty Bay (showing deeper depths)

HI1530 Lidar – St David’s Harbour to Prickly Bay (showing new shoal and rocks)

Aims of this Presentation

• UKHO requirements and use of Lidar data

• Our understanding has increased, and charting utilisation of Lidar data has improved

• Data comparison between older and newer Lidar technology

• Data density has got much better – but need to prove object detection empirically

• Successes

• UKHO are efficiently updating many nautical charts using Lidar surveys

• Challenges

• IHO Order 1a standards – and proving it.

• Disproving depths/features using only Lidar

Conclusion

• Aspirations to meet IHO Order 1a are still not met – density has improved greatly, but object detection is still not comparable to MBES. More to be done.

• Lidar is still an extremely valuable tool for updating charts, and provides value for money in many coastal areas compared with acoustic systems.

• UKHO continue to push the private sector to drive lidar technology forward, and help increase coverage of poorly charted areas.

• Empirical object detection always required until technology proven.

Planned Lidar Surveys -Turks and Caicos Islands

• Survey Area: 7277 km2

• Survey Area: 2379 km2

Planned Lidar Surveys - Belize

• Survey Area: 2016 km2 AW Hydrographic

Planned Lidar Surveys – British Virgin Islands