Integration of Multibeam Echo Sounder (MBES) and Airborne LiDAR bathymetry (ALB) and topography data for S57-compliant ENC Charting Surveys

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1 Integration of Multibeam Echo Sounder (MBES) and Airborne LiDAR bathymetry (ALB) and topography data for S57-compliant ENC Charting Surveys Authors: Don VENTURA (Fugro Pelagos Inc.) United States of America, (Presenter) Chris SPENCER (Fugro OSAE GmbH) Germany Contributors: Mr. Mohammed Hamid AL HARBI (GCS) Kingdom of Saudi Arabia, Dr. Eid Moosa AL MOTAIRI, (GCS) Kingdom of Saudi Arabia. SUMMARY The successful 2010 MBES/LiDAR Charting surveys to the North of Jeddah, Kingdom of Saudi Arabia, were conducted in a co-operative programme by Fugro for the General Commission for Surveys (GCS) to IHO S44 Order 1a, 1b, & 2. Field-work elements were completed the over a 3 ½ month period to June This project followed another technically successful, albeit simpler, MBES/LiDAR integrated programme of works for the new Jazan Economic City in the Southern Red Sea, again in Saudi Arabia, which completed in June 2009 for the Jazan Economic City Land Development Company. The acquisition programme at North Jeddah was completed as a government-sponsored pilot programme for the newly formed (at the time of survey) GCS, which is charged with administering maritime charting and terrestrial mapping in the Kingdom. The North Jeddah Project consisted of nearly 4000km² of combined LiDAR and MBES survey across complex shallow water (coralline) barrier reef coastal margins and the typical deep Figure 1: (N - S) North Jeddah and JEC Surveys, Kingdom of Saudi Arabia water of the Red Sea rift area; this also included a narrow 3km band of coastal topography. This paper highlights the proven integration of the survey-platform paradigm, and thus data, for the successful delivery of a comprehensive programme of works to achieve superior results in a difficult marine and terrestrial environment. 1. THE PROJECT ENVIRONMENT IN THE KINGDOM OF SAUDI ARABIA The Kingdom of Saudi Arabia (KSA) is one of a few significantly fast-growing countries in the world, characteristically with a high per-capita income and an increasingly predominant, educated and mobile young population. With the resultant and ever-increasing demand for an improved standard of living, based on predicted per capita income within the Kingdom, His Majesty, The Custodian of the Two Holy Mosques, King Abdullah bin Abdul Aziz Al Saud, has decreed an ambitious and spectacular programme of development already effected over the past few years. The basis of these initiatives, driven by the Saudi Arabian General Investment Authority (SAGIA), are the formation of four new industrialized cities in a deliberate strategy to diversify the economy of Saudi Arabia. The ultimate aim of this scheme is an expected increase in the per capita income, contributing an estimated US$150 billion to the GDP. 1/8

2 In turn, the overall regional development plan has created an initial focus on the need for landward and seaward spatial information. This has been found to be paramount in nearly all of the latest proposed developments, over-and-above the ever increasing demands on the existing environmental and industrial infrastructure already in place. The Government has effected a programme to-date towards addressing the IMO/MARPOL/UNCLOS (24 April 1996) and other maritime obligations, inpart based on areas of significant maritime activity in the Arabian Gulf. However, the predicted increase in shipping within the Red Sea following the construction of the 2 new economic cities on the Kingdom s Red Sea coast (King Abdullah Economic City (KAEC) and Jazan Economic City (JEC) and their incumbent commerce, has dictated a need for the revitalisation of existing facilities, examination of proposed safe-passage deep water routes shoreward, and an evaluation of the marine environment for long-term resource management. As experienced in both projects featured in this paper, the spectacularly diverse Red Sea environment, consisting in part of tropical barrier reefs, deep water channels and alluvial fans, has historically been poorly charted due to the low utilisation of the areas maritime resources. Existing charts ranged, at best, from a comprehensive but resolution-limited Saudi SBES programme of charting surveys from the 1980 s, back to 1930 s era Italian submarine-based charting and 19 th Century British and German charts. The quality of charting therefore was directly attributable to the original survey projects scope-of-work and the degree to which in-field adjustments had to be implemented to ensure that all areas of the survey were acquired by the appropriate sensor and platform. Coralline structures and features on a macro-mega-scale were observed, and will undoubtedly lead to further understanding of reef morphology in the Red Sea, historical sea-level fluctuations and the impact of construction and development on this unique environment. 2. THE PROJECT CLIENT GROUPS 2.1 Jazan Economic City (JEC) Located 65km northwest of Jizan City, KSA s southernmost port on the Red Sea, Jazan Economic City (JEC) is the Kingdom s new state-of-the-art industrial economic city, to be built over 20 years at a development cost of approximately US$30 billion. JEC is ideally situated on the coastline of the Red Sea to become an important logistics hub, a major destination for regional raw materials and an export platform for global consumer markets and is in close proximity to the main east and west sea trade routes to Europe, the Far East and the Arabian Gulf. As such, JEC is expected to attract more than SAR100 billion in investment, 100,000 new jobs and epitomise the principles of the Kingdom s development programme. The JEC Developers included MMC Malaysia Co., one of the Malaysia s largest companies, supporting various services such as transportation, logistics, energy, ports, engineering, and construction; and the Saudi Bin Laden Group, an internationally recognised company with assets that exceed more than US$4 billion and whose resource includes more than 60,000 employees worldwide. (SAGIA & SBLG websites) 2.2 General Commission for Survey (GCS) The General Commission for Survey was established in accordance with the Royal Saudi Council of Ministers Resolution No.(8) dated 13 Feb As the leading national organization in survey, mapping, charting, geographical information and hydrographic survey, the GCS mission centers around the production and marketing of geo-spatial survey information and services, improving relevant technologies, high quality manpower training and development, and cooperation with GCS partners to meet user and decision-maker requirements. The Commission s main goal is to carry out geodetic, topographic and hydrographic surveys, the production of maps at 1: 25,000 and smaller scales and the establishment and development of geographic information systems relevant to the GCS activities. To achieve its main goal, GCS undertakes tasks, including but not limited to, the following: Develop, implement and maintain technical specifications for geodetic, topographic and hydrographic survey works. Carry out aerial photography related to its works as well as coordinate, arrange and oversee the aerial photography activities done by other parties. 2/8

3 Establish and maintain geodetic networks to support GCS activities and conduct earth gravity measurements as needed, as well as carry out appropriate measurements needed for hydrographic charting. Conduct and sponsor research and studies on the survey disciplines relevant to the GCS field of specialty and provide consulting services in the field. Market and sell its digital and conventional survey products and services and publish its unclassified products from survey and geographical information. Establish and execute training and development programs relevant to its areas of specialty, as well as addressing the professional development needs of national cadres, within and outside the kingdom. GCS is also referred to as the General Authority for Survey; chairmanship of the Board of Directors of GCS is held by H.R.H. Crown Prince Sultan Bin Saud Bin Abdul Aziz Al Saud. GCS is currently under the Directorship of His Excellency Abdullah Al-Shahrani, who has been charged with controlling and developing the geographical spatial information acquisition and delivery services for KSA. This includes both terrestrial and territorial marine information. 3. HYDROGRAPHIC SURVEY PROJECTS JAZAN AND NORTH JEDDAH 3.1 Jazan Economic City Approaches and Port Survey In 2009 the Fugro operating companies (Opcos), Fugro OSAE GmbH (FOSAE) and Fugro Pelagos Inc. (FPI), in conjunction with the local Dammam-based Fugro Suhaimi Ltd., carried out a hydrographic survey to IHO S44 Order 1 accuracy standards of an approximately 1400km² area, 65km north of city of Jizan on the South-eastern border of KSA and Republic of Yemen. The approaches, starting from the KSA Territorial limits of the Red Sea, ran towards the proposed anchorage and Port area, site of the new JEC (Figure 2). Figure 2: JEC Approaches and Port Combined MBES/LiDAR Survey with Port concept diagram JEC s Technical Representatives, the United Kingdom Hydrographic Office (UKHO), issued Hydrographic Instructions: HI JAZAN and HI JAZAN COASTAL. These were originally bid on conventional vessel-borne MBES and SBES technologies. In discussion with the client, it became obvious that, due to the rapid turn-around requirement and the nature of the shallow water (<20m) Port development area, that the best solution was an airborne LiDAR (ALB) bathymetric survey for the coastal margin. A solution for the combination of Airborne LiDAR and vessel-borne MBES was subsequently selected by the UKHO and Client, and work commenced in February /8

4 The areas consisted of terrestrial foreshore / shoreline and beach, coral reef, and deeper water fan and channel structures. Rapid assessment of shoal features in the field during survey data acquisition led to subsequent route changes by the UKHO and extension to the areas of survey. 3.2 North Jeddah Survey In 2009, a pilot hydrographic IHO/ENC charting project North Jeddah or The Red Sea Coastal Zone, area between Sha ab Naza and Sha ab Al Kaber was identified by GCS and opened for tender for an IHO S44 Order 1a & 2 Survey suitable for ENC/charting use. The Pilot programme was to develop both the hydrographic contract supervisory roles of GCS management and to assess the level of effective acquisition in a typically diverse Saudi marine area. The survey was considered of interest to various stakeholders in-kingdom, not least the dynamic requirements of the Kingdom s main Red Sea Port at Jeddah. A Fugro bid won the Contract based on a comprehensive combined LiDAR/MBES programme, again provided by FOSAE and FPI, and a proven performance record and delivery from the Jazan survey earlier that year. Figure 3: North Jeddah combined MBES/LiDAR survey area. (From left) Original Saudi chart, project-designation of LiDAR/MBES, and final combined acquired MBES/LiDAR survey results The pilot programme incorporated, contractually, a significant flexibility to extend the planned survey area to meet the immediate demands of any information stakeholder. EMAAR Properties PJSC of Dubai (EMAAR), representing the developers and specifically the new port construction at King Abdullah Economic City (KAEC), were able to communicate their interests to GCS for the acquisition of additional bathymetric data just north of the survey area as originally perceived, incorporating the approaches and route area for the new port. Subsequently, GCS issued instructions for this to be carried out and the UKHO-supervised IMO submission for the Approaches and Routes to the new King Abdullah Port were presented by EMAAR in submission before the IMO in July PROJECT OBSERVATIONS 4.1 Project Management and Support Structure The Fugro team featured within this paper included, but was not limited to, the main survey companies FOSAE and FPI. Considerable reliance on a support infrastructure and technical expertise within the Fugro Group on both projects saw the successful execution of relatively complex surveys due to the strength of a combined effort by up to seven different Opcos. Whilst this enviable strength-in-depth is a huge asset in attempting these large and often remote surveys, a strong, 4/8

5 knowledgeable and communicative project management approach is vital to the ultimate success of such a project. The diversity of the sensor technologies employed to execute these surveys was such that, essentially, the data acquisition and processing teams operated as standalone but interdependent units; this paradox makes more sense when one considers the diverse data collection and management routines which have to be employed for a rapid, relatively point data-sparse airborne system (compared to modern multibeam sonar technology) operating from a nearby shore base and collecting data in the complex near-coastal fringe, and a slower seaborne platform collecting very dense high resolution data offshore. Management team understanding of the issues such a combination generates is crucial to the success of such a project. For this reason, FOSAE was nominated to lead both projects due partly to work-share but more significantly to the more protracted data collection time and therefore time in-theatre for the survey vessel and crew, compared to the typically shorter timescales experienced by the airborne LiDAR team. 4.2 Acquisition Parameters and Logistics Synergy Initial assignment of the survey polygons was established in both projects based on the operational efficiencies and limitations of the main bathymetric technologies. Data density requirements, particularly for LiDAR, were pre-calculated in order to achieve the appropriate seabed coverage and target detection criteria specified in the associated contract specifications. LiDAR was optimized in all areas where navigation hazards and/or shallow water were considered significant to either crew and vessel safety or operational efficiency (due to reduced swath coverage) of the MBES systems (Figure 3 above is a good example of this approach). By accepting a conservative limit for LiDAR penetration but equally conservative for ship safety, a healthy data overlap was assured and this facet of operations, subject to amendment as the survey progressed for the reasons provided below, greatly aided the complex data merge operation during the final processing stages of the survey. In order to effect a concentrated data collection phase with relatively few personnel on each team, Fugro utilized the aforementioned strength-in-depth in order to establish the critical geodetic and tidal infrastructure for both JEC and North Jeddah. Although lead project management was assigned to FOSAE, FPI s shore-based presence allowed for an effective field operations hub to be available to the supporting entourage of Opcos, and to identify with and report progress to the main project team. This was also advantageous for the respective clients, particularly GCS, who enjoyed access to the survey team not normally possible during major hydrographic work. This led to an excellent understanding all round; crucial in a pilot programme and survey as complex as that encountered particularly in North Jeddah. 4.3 Field Assessment and Team Communications Daily internet dialogue between the MBES team onboard the ship and the LiDAR team, reinforced with regular meetings during the vessel s port time for crew change-overs, replenishment and minor maintenance, ensured that the otherwise operationally-independent teams could discuss progress, compare data coverage, clarify issues and identify and resolve potential problems. The rapidity of the LiDAR data collection was used to regularly update the vessel on the degree and extent of the overlap required due to the highly variable bathymetry encountered compared to that planned from the existing data on the charts; this was especially true of the Jeddah project which encompassed some spectacularly complex coral reef and massive changes to the contiguous coastal land use and therefore topography. For JEC this was an easier task but the survey conditions were more variable and so a careful assessment of appropriate data quality parameters had to be employed to ensure that the survey vessel could rely upon the near shore work implicitly in order to allow concentrated effort in the very linear and extensive main approach channel work. Without these strategies employed to execute these projects, the very flexibility demanded of the teams due to the variance between historic data on which the surveys were planned and the actual conditions identified would have been insufficient to appropriately manage such change. 5/8

6 4.4 Processing, Records and Reports Paramount in the minds of all project personnel was the need for careful evaluation of acquired data, with no room for complacency when evaluating areas for survey coverage based on the original charts. In both projects, all existing data was found to be fraught with erroneous depth records, obstruction details, wreck locations, sailing directions and other observations. As a result, numerous hydrographic notes were created from the information gathered and issued from site, (over 130 from the North Jeddah survey alone). Route changes in at least two places were significantly altered and in one project the area for survey extended (as described above) to allow new route planning. As in the preceding planning and data acquisition phases, communications, updates, strategies and issues were predominantly featured during the processing phase. Although the routines and data assessment techniques employed by the teams were very different, a common framework ensured that the data underwent the same degree of cleaning, editing and control and within the same geodetic framework parameters. A parent Report of Survey (ROS) was adopted and various compilation and editing tasks agreed to earlier in the survey planning phase. The process of carefully apportioning the survey areas during the planning cycle was reflected in the breakdown of records and reporting for the survey as a whole. In so doing, the team avoided un-necessary repetition of work and this in turn led to an efficient reporting structure for the surveys. Figure 4: FPI s SHOALS Bathy LiDAR Detected Feature Cell 22 - (left); 3D-oblique & aerial views, and (right) MBES wreck investigation results. Processing was conducted independently and fully on both the multibeam and LiDAR data in such a manner that either dataset could be considered a fully complete and holistic survey within its own geographical boundaries, although as described, the reporting was a joint assembly between the main contributors. Overlapping limits were compared in a slightly iterative process as both teams ensured that final coverage of fully processed data did not differ largely from the final tasking generated during the agreed data acquisition infill work. A measure of the synergy within the team, and the resultant data quality which this managed integration supports, was exemplified in the featured product as seen in Figure 4 above, which highlights the identification and evaluation process during wreck investigations using a combined airborne and vessel based solution. 4.5 MBES/LIDAR Bathymetry Data Merge and Final Products Generally, superior data density and data point resolution exists for MBES systems over bathymetric LiDAR, and because of this, prioritization of overlapping data during data merge ws a relatively simple one. Despite significant tracts of deeper survey margins being successfully obtained by LIDAR, MBES coverage reigned in these areas and in order therefore to avoid potentially high standard deviation values in such overlap, LiDAR data was trimmed to the agreed overlap boundaries before final delivery to FOSAE for data merge. After receiving the final LIDAR data set, Caris HIPS was used to incorporate the data within the project structure also containing the MBES datasets. This solution offered the flexible incorporation of any infill data collected by MBES, SBES or LIDAR data, and a final base surface was derived of all data within that area. Application of final tidal modelling and any geodetic adjustment could then be applied to one final, fully- incorporated data set. 6/8

7 From this data campaign, GCS were proud to develop and issue their very first national ENCs built entirely in-country, which were published at the beginning of Subsequent surveys conducted under the same GCS-administered program have added further data holdings and scope for continued progress in the national digital chart upgrade program. The adequacy of such charts of highly complex coastal areas is largely down to the holistic approach taken to the acquisition of survey data, utilizing multi-sensor technology to generate the necessary seamless datasets. Acknowledgements An earlier version of this paper was prepared for the Hydro 2010 Conference, which was held in Rostock, Germany. The authors wish to thank Dr Eid and Mr. Al Harbi of the General Commission for Survey, KSA, for their support of this original paper and in working closely with the Fugro Group in the development of a successful hydrographic survey programme at North Jeddah. REFERENCES Links: Ministry of Foregin Affairs last accessed on 09 September, Saudi Arabian General Investment Authority, last accessed on 09 September, King Abdullah Economic City, last accessed on 09 September, Emaar, The Economic City, last accessed on 09 September, Jazan Economic City, last accessed on 09 September, Saudi Bin Laden Group, last accessed on 09 September, MMC International, last accessed on 09 September, /8

8 BIOGRAPHICAL NOTES Don Ventura, a Scot, is Hydrographic Survey Manager at Fugro Pelagos Inc. An IHO Cat A accredited charge surveyor, Don has over 27 years of hydrographic survey experience including two decades with the British Royal Navy, 3 years with the US Naval Oceanographic Office and has been providing hydrographic expertise to the FPI SHOALS programme since He currently lives in Louisiana with his wife and his daughters are both at university in the States. Chris Spencer, a New Zealander, joined the Fugro Group of companies in Southeast Asia in 2006 and joined Fugro OSAE in Bremen, Germany, as a Projects Manager in He has had a varied career starting in the survey industry in 1977 and following international onshore and offshore assignments, has included boat building, military and police roles during this time. He entered parttime studies at Otago University in 1990, finally completing Post Graduate studies in Surveying, Geology, and Marine Science in From he was given the task of developing and managing the hydrographic surveying courses for transition to the IHO, Cat A and Cat B levels offered today. Chris has since worked worldwide within the marine seismic industry, construction engineering, and representative supervision, before joining Fugro. He currently lives with his wife and children in Niedersachsen, Germany. CONTACTS Mr. C. A. Spencer Mr. D.C. Ventura Fugro OSAE GmbH Fugro Pelagos Inc. Fahrenheitstrasse Ruffin Road Bremen D San Diego GERMANY California, USA Tel. +49 (0) Tel Fax +49 (0) Fax spencer@fosae.de dventura@fugro.com Web site: Website: 8/8