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Responding to emergencies is something that we are well placed to do due to our central location in the UK and the fact that we can mobilize a team and equipment quickly. Recently we took a call from a long term customer asking for an emergency topographical survey of a burst embankment on the River Mersey in Manchester. The survey needed to provide an overview of the current status of the embankment and inform a repair plan. On arrival, our actions were to carry out a topographic survey of an area approximately 200m long, extending from the top of the bank to five metres beyond the dry side of the flood embankment. Each survey interval was to be at around 10 metres for undamaged areas and tightened up to show damaged areas at a suitable resolution. We also needed to take photographs for the record. We knew that there would be a helicopter onsite for some of the time, dropping off bags to shore-up the embankment, so we had to work in tandem.
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Sometimes we are contacted by customers who have had a survey conducted by another surveyor, but for a variety of reasons it has not quite met their requirements. This was the case recently when we were asked to conduct a survey on a lake in Northern Ireland, to fill gaps in a previous survey conducted by another surveying team. The lake had been partly drained and the survey was required to help inform the client of volumes. The client had appointed a local firm to undertake the works and, whilst the quality of what they managed to survey was perfectly adequate, they were unable to complete the full extent of the survey due to the margins of the lake being very soft and overgrown and thus unreachable. The parts below in Cyan were missing from the previous survey:  To infill these areas, we sent a team of three experienced surveyors including a trained boat skipper and trained drone pilot, equipped with total station, GNSS unit, laser scanner, survey grade drone, boat, sonar depth unit and 10m air track rafts to assist with access over soft ground. Taking this amount of specialised equipment and trained team members meant that we could assess the viability of conducting a laser scan or drone survey based on the level of vegetation, visibility, ground conditions and weather, and assuming that neither would provide sufficient results we had the boat on stand by to survey the water line plus additional levels either side of the water line. The trip duration was kept flexible, with a view to capturing the required areas by the quickest and most effective methods. The results of the infill survey were added to the existing survey and reissued as a 3d topographic survey in autocad .dwg format. The National Gallery celebrated its 200 year anniversary earlier this year, and big celebrations were planned! Our friends at Creative Technology were commissioned to project a video onto the front of the building to entertain the visitors to their NG200 event, and we were commissioned to survey the front facade of the Gallery and provide a 3D model to enable the mapping of the video projection.
Due to the intricate detail on the building exterior, extremely high quality point cloud information was required to enable an accurate and detailed 3d model to be produced. Normally the level of detail required from the model will depend on the type of content and elements of the building that the client wants to pick out in the projection, and as this particular projection targeted individual string courses, a high level of detail was required.
To scan the building we used a Leica RTC360 laser scanner with high accuracy tilt enabled. The data was then cleaned and registered in Leica Reg360 and the resultant point cloud was then modelled in Rhino, delivered to Creative Technology ready for mapping.
 "A truly professional service provided by Grantham Coates Surveys. Having now worked with them for many years on numerous Projection Mapping Events they always provide us with highest quality scans and models for our projects. They are very easy to deal with and will always go above and beyond to try and fit in with the tightest of work schedules."
Paul Seeger at Creative Technology Ltd THE PROBLEM Back in July we conducted a Drainage Survey of a huge piece of land in Curdworth, Sutton Coldfield, to inform a drainage strategy. Previous investigations that the customer had conducted using CCTV and Risk of Flooding from Surface Water (RoSW) data had not provided a good overview, and the drainage connectivity of the site was unclear. Initially our client came to us with the following brief; “We are working on a project which requires a bit of problem solving, initiative, or maybe a new approach to trace some drainage downstream of our clients site. A couple of survey companies have tried, but have not quite delivered.” The CCTV that had already been conducted of the underground pipework was inconclusive as to where the pipework ended and subsequent outfalls were, and indeed if there was a good connectivity downstream of the site that could be sustained in the long term. THE SOLUTION Using a combination of CAT and Genny with FlexiTrace, metal detectors and CCTV we located a large number of additional manhole covers that were not on the original topographic survey or CCTV reports. Many of these covers were deep in vegetation or buried, so needed to be completely dug-out.  By taking a staged approach in bringing all the possibilities of how the site drains connected, we were able to drive the investigations and achieve the aim. The early stages included an initial walkover of the site, lifting manholes, sounding manholes, using FlexiTrace connectivity where possible. This led to interpreting the findings and recommending the next steps.  Next we unblocked pipes using a jetter and then conducted CCTV to progress the survey. Finally we conducted a supplementary survey to infill the missing data not discovered in the early stages. When we established the drainage connectivity on the site, all pipes and outflows needed to be assessed for condition and material, a CCTV survey was carried out to provide a condition survey as well as the accurate layout plans.  “The client came to us for help in analysing information from various sources, each bit of information was incomplete. Whilst each of the previous visits had found out a little bit more, it needed someone to take responsibility for driving the investigation forward. We achieved this using various techniques, engaging sub contractors over multiple visits, always focusing on the end goal. We have left the client with a much better understanding of the drainage routes enabling them to progress their project.”
Chris - GCS Surveyor managing the project. Scour surveys are imperative for the Rail Industry to keep their infrastructure in full working order. Often, damage or wear and tear to assets such as railway bridges can go unnoticed if it is below the waterline, so surveys need to be carried out to assess the damage and make recommendations for repair. In order to gain a clear picture about the health of a railway structure such as a bridge, a Scour Assessment Survey is needed. The survey will be conducted across various parts of the bridge as well as upstream and downstream of the structure. The survey will produce upstream and downstream cross sections, bed levels and photographs to enable hydrological models, depth and flow velocities to be calculated.  The results of this survey will produce an ‘at risk’ rating of low, medium or high and, if medium or high, a more extensive Scour Protection Survey may be required in order to inform the repairs that will need to be made to the bridge. This Scour Protection Survey is designed to be more in-depth and will include upstream and downstream elevations/cross sections, full Topo of bed levels, location of any coring, hydraulic modelling of the watercourse and photographs. Unlike land or building surveys, scour surveys are more complex because data needs to be collected above and below the waterline, which involves the use of a number of pieces of equipment and diversely trained Surveyors.  At Grantham Coates Surveys we have years of experience in conducting surveys for Scour Protection and our team are trained to carry out surveys in conditions that can be tricky and ever-changing. We use the latest laser scanning technology to collect bridge elevations, abutments and pier details quickly and effectively, whilst our boat team can be deployed with an underwater sonar to capture point cloud data of the bed levels and everything that cannot be seen just by wading; such as submerged posts, undercutting of abutments and bed materials.  When the Scour Protection is complete, the data is used to create detailed 3D drawings of the state of the bridge above and below the waterline so that design and build work can be informed and planned. Without Scour Assessment and Protection Surveys, damage to rail infrastructure caused by flooding and unpredictable weather could go completely unnoticed until it is too late, so form an essential part of rail infrastructure maintenance.
Last year we decided that using a drone to bolster our surveying services would be a good idea, so we set about applying for a license. We knew that the application and training process wouldn’t be a walk in the park, but nothing really prepared us for the time, effort and investment we would have to make in order to get our approval from the Civil Aviation Authority. As we want to fly our drone commercially (in other words for a fee) then we have to prove that we are not only competent to fly a drone, but that we are willing to take on the responsibility of being in charge of a UAV and deciding whether or not it is safe to fly without being a danger to anyone or anything in the area. The training we undertook included theoretical and practical exams, hours of flying time and awareness tests. We had to complete a complex operations manual and seek approval from the CAA, and only then were we able to achieve our Permission for Commercial Operation (PfCO). Since then we have adopted parts of the ops manual into our current risk assessments that we have for every job we do, so we are constantly adapting our processes and weighing up factors such as weather and safe launch areas for every flight. So how do you go about finding a CAA approved Drone Pilot? Anyone that flies a drone for ‘commercial gain’, is breaking the law if they do not have the right license. Without this they cannot obtain the right insurance, so if anyone gets hurt in the process then there is no policy in place to cover the unthinkable. We are accredited and insured, anyone who can’t say the same is not legally allowed to fly. A commercial pilot will be listed with the CAA so their website is the best place to look, or you can search the Drone Safe Register by location to find your local pilot. Once you find a pilot and drop them a line, you should expect them to ask you a number of questions about your project, as they will be deciding whether or not they can take it on. Once they have established the type of location, the risks, the equipment they might use and the legal requirements, only then will they be able to send you a quote. Taking responsibility for their own equipment and the safety of anyone in the immediate vicinity should be top of your drone pilot’s list, so choose one who is compliant, safe and accredited. If you have a project in mind that may benefit from drone input, get in touch with us today on 01789 764420. At Grantham Coates Surveys we carry out topographic surveys in all manner of environments and were recently commissioned to carry out surveys on numerous hectares of forest. The deliverables here were standard topographic 3D surveys showing all trees over 300mm, but knowing from experience that these types of surveys can often be extremely time-consuming, we decided we needed to find a way of speeding up the process in order to avoid extended project timescales and thus higher fees. Proudly we regularly evaluate our workflows, equipment and technology to continually improve our working practices, and decided to run an experiment to see how we could speed up a forest scan without compromising on the quality of the data. We therefore compared standard terrestrial laser scan data from a previous 30 hectare forest survey in 2018, with a sample collected in our local forest with the new GeoSlam Horizon handheld scanner. Not only did the GeoSlam Horizon have a greater range, but with the assistance of James Philips from Korec we discovered that the data collected also had reduced errors across the area being of the order +-20mm. The result of this meant that using the GeoSlam Horizon and a combination of GeoHub, Cyclone and LSS Point Cloud to process the data into a full 3D topographic survey, would take less time and therefore at a lower cost to our client. Using the GeoSlam Horizon enabled us to provide a forest survey that contained more information than could be captured using more traditional methods. We achieved:
 GeoSlam Horizon in action!  One Zeb Horizon data set. All captured from hand held ground level scanner.  Our location in the forest during the scanning process.
At Grantham Coates Surveys we pride ourselves on continually innovating, developing and investing to stay both current and ahead of the field in all aspects of land surveying. To this end we have trained two UAV drone pilots and gained the all important CAA license to enable us to fly commercially. We see UAV surveys as another tool in the box. UAV’s along with our laser scanning, sonar scanning and traditional survey tools make us well placed to carry out any survey anywhere in a timely, safe and cost effective manner. UAV surveys provide a remote controlled platform from which low level imagery can be captured. Some of the advantages of UAV surveys are:
 Above: Farm complex UAV Survey UAV Survey of railway embankments. Deliverables:
The survey was carried out quickly and without the need for direct access line-side.  Above: 3D Model Below: 3D views of data captured along with plan Orthographic tiff image    Protection of our coastal communities is an ongoing challenge. Hard engineering techniques including rock armour and concrete structures are used throughout the UK to deflect the power of waves, helping to reassure coastal communities and protect our beaches. Working with such structures carries many challenges and risks meaning that surveys are a vital step in any repair, renovation and improvement works. Back in 2017, working alongside Balfour Beatty and JBA Consulting, we were commissioned to provide survey works to assist in the repair and improvement of sea defences consisting of rock armour revetment and sea wall in East Rhyl. Revetments are sloped structures built along coastal frontages that absorb the energy of waves breaking against them, thus helping to reduce coastal risk. Rock armour involves placing large boulders in front of a cliff or sea wall to absorb the energy of waves. Used in conjunction these structures are a powerful means of energy absorption and protection.  Our role as part of this project was to provide detailed topographical surveys with both 2d and 3d outputs compliant with BIM level 2 to inform the improvement works.  Using a combination of techniques including, GPS, total station and laser scanning we performed a mixture of high density and low density surveys as follows:
Whilst seaside working provides a beautiful setting, it also carries with it challenging weather conditions and lots of risk factors. Working near a tidal body of water meant that timing was of the essence, both in terms of survey accuracy and health and safety. Being November, we also had weather factors to contend with. During the course of the survey it was identified that the beach level change significantly between tides. An indication of which area of beach was surveyed each day was added to the final drawings Below: Laser scan data covering sea wall, rock armour and foreshore. Draft survey data showing areas of levels surveyed on individual days   Below: 3D model generated from the laser scan alongside traditional total station promenade survey  “Grantham Coates have been invaluable in supporting the development of a 3D model suitable for the construction of the East Rhyl defences. We were able to discuss through our requirements and explore relative advantages and disadvantages of different survey techniques. This meant that the deliverables provided by GCS met our needs and avoided any need for further post-processing.”
Alec Dane JBA Consulting To read more about out topographical survey work, click here. If you’d like to discuss a project of your own, contact us on 01789 764 420 or email [email protected]  In April we posted on our Social Media channels that we were extremely proud of the results that Marcin, one of our Trainee Surveyors, was gaining on his TSA Surveying Training Course at The Survey School, and that prompted us to think about all the other training our team has undergone in order to do the job they do.
Now, as Surveyors there are lots of accreditations that we have to have in order to undertake the variety of work we are presented with, from working in water and working on the rail, to medicals and first aid. The most recent course we sent some of our team on was ‘Power Boat Handling’. Not surprisingly the most popular course so far…. We chose the ‘TSA Surveying Course for Surveyors’ qualification for Marcin for a number of reasons; one of which was that two of our employees also previously passed the course and found the experience invaluable, but also because the course is accredited by the Chartered Institution of Civil Engineering Surveyors, of which we are also members. Not only that, but the course is designed for trainee surveyors who already have a fair amount of experience surveying but no formal qualifications in the field, so Marcin was the perfect candidate. We think that Marcin would agree that although the course is going to provide him with the springboard he needs to progress in his career, it is not going to be easy. The course is designed to put trainee surveyors through their paces and prepare them for the varied world of surveying, so it covers a lot of topics in a lot of depth. However, if Marcin keeps progressing at the rate that he currently is (having just scored 94% in Block 4 Measured Building and Specialist Surveys) then we are confident he will finish the course a highly proficient and capable surveyor. To give you a further bit of insight, our surveyors are also trained in or hold the following accreditations:
So aside from actually conducting surveys, processing the collected data, producing the finished model and working to a tight deadline, our surveyors are also constantly keeping themselves up to date with the necessary skills and qualifications that our industry demands. Don’t let anyone ever tell you that the life of a Surveyor is an easy one! |
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Grantham Coates Surveys Limited
2 Arden Court Arden Road Alcester Warwickshire B49 6HN |
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