SEP are industry experts and truly a one-stop-shop for your topographical and surveying needs.
Our land survey team are experts in highlighting all manmade and natural terrain with levels, presented with, if required, utilities and drainage mapped out on a scaled survey drawing completed by our own technicians.
Whether it’s a small scale building extension or a multi-million-pound development, the level of detail surveyed and shown is tailored to individual needs and specifications for any design, development or feasibility construction requirement. We aim to make your life easier by having in-house topographic survey experts and supporting departments who can be called upon when needed.
All SEP surveys are provided to Ordnance Survey Grid and Datum and supplied in a wide range of 2D and 3D formats. Our 9 years in this field allows us to further assist you with future-proofing 3D information including earthwork calculations, visibility analysis, tender analysis, volume appraisals and visual walk-throughs.
What is a topographical survey?
A Topographical Survey (or Land Survey) is a pinpoint mapping method giving an accurate representation of an area of interest. Topographical surveys are most commonly prepared by land survey teams to provide information including a scaled drawing representing the land contours, terrain and other site features with an extremely detailed degree of precision.
The resulting information can be used in a wide range of applications including, but not limited to:
- Site plans and layouts for construction.
- Property boundaries and subdivisions.
- Estate planning.
- Site Management Plans (SMP) for mining, forestry or agricultural purposes.
- Construction, Mining & Forestry Development
The benefits of performing a topographical survey
The main benefit of performing a topographical survey is to provide precise and detailed information at an early stage of natural topographic features, physical boundary details, natural and manmade features adjacent to the site including drainage details and spot levels to enable the design team to proceed with their plans. Conducting a topographic survey gathers data that can reduce the risk of costly mistakes down the line, potentially including minimising the risk of damage or injury to people, property and equipment.
When is a topographical survey needed?
We work for a wide range of large and small companies: Architects, Civil engineering companies, major Contractors and the odd Premier League Football Club. We have worked with them all to help them achieve their vision. From a domestic home extension, through to the major commercial developments, from roads & drainage design and specification, public footpath mapping or legal boundaries – we can assist you in your land surveying need.
Typically, topographical surveys are used to acquire accurate data as a base map for design and development projects. If you are planning to undertake any construction or building work on a plot of land it is important to carry out a topographical survey prior to beginning any design work. We acquire our data by carrying out surveying work on-site which we then use to produce a survey plan, presenting accurate scaled drawings representing the land contours, terrain and other features.
What is involved with planning a topographic survey?
If you are preparing a topographical survey it is important to understand the land and surroundings of the area you want to be surveyed. Topographical surveys can be used to gather data of site boundaries, site features, existing buildings, natural and manmade features, physical boundary details, drainage details, land features, tree positions, as well as additional details.
Typically the topographical survey process involves:
- Defining the scope Establishing when and why the survey is required, the location and boundaries of the area to be examined.
- Project pre-planning - Enables the survey team to understand the complexities of the project, access points, obstructions, services, utilities and any other constraints which could affect the survey.
- Data acquisition - Surveying both natural and man made site features via a variety of means including a range of surveying techniques tailored to the project requirements.
- Data processing and QC - The data captured during the field survey is processed and analysed to ensure the data acquired meets the project requirements.
- Final deliverables and presentation - The final product is presented to our clients in various different formats including; written reports, accurate scaled cad drawings, presentations and 3D visualisations.
What equipment is used for topographical surveys?
Topographical surveyors use highly specialised survey equipment to perform surveys. All of these tools will collect, record and measure the data needed to produce both one-off reports for smaller surveys or larger volumes of work, right through to large scale topographical surveys. Not every survey project is the same, so different methodologies are used when surveying in order to meet specific needs and requirements. Land surveyors will typically work with each other to ensure the correctness and reliability of data, which is then processed into a final product that can be used for planning or building purposes.
Topographical surveys are performed in the field using highly specialised survey equipment such as total stations, RTK GNSS devices, digital levels and laser scanners. In some cases, topographical surveys may also use drones or digital photogrammetry software to extract data from aerial images, but this will typically be more of a supplement than a replacement for more traditional methods.
The survey spread selected will be dependent on the terrain and the level of information required, but typically includes a combination of:
Electronic Total Stations - The standard surveying equipment in use by most land surveyors, these high-precision instruments are used to measure distances and angles.
RTK GNSS - RTK GNSS units locate a user's position with a base station, typically located in another location. This gives land surveyors accuracy from 1mm to 4mm which enables them to achieve results where traditional methods have been less successful.
Digital Levels - Digital levels are used for accurate site levels and setting out of both horizontal and vertical surfaces. These can also be used to verify the precision of other tools.
Laser Scanners - Surveyors use laser scanners as part of a land survey to take accurate 3D point cloud data and vector models of both natural and man made features, land surfaces and other objects.
Drone-based Photogrammetry or LiDAR - Land survey teams may perform aerial surveys as part of a topographical survey using drones outfitted with 3D sensors such as LiDAR or photogrammetry cameras. These provide highly accurate data on a larger scale area of land than traditional topographical surveys and can be used for open terrain, property or sites that present challenges in terms of access.
Laser scanning and topographic surveys
With the increased availability of reasonably priced laser scanners, their use in topographic surveys has increased alongside traditional methods. These devices are typically used to supplement existing survey data and provide a higher degree of detail than more traditional techniques such as RTK GNSS or electronic levels. Some project specifications may even specify that both types of equipment be used on-site at the same time, and all data is then processed using emerging photogrammetry techniques.
The precision of measurements improves as the distance between the equipment and the surface being examined gets smaller. Laser scanners allow surveyors to acquire very precise metric information to form an accurate picture of a small object or surface area by collecting millions of points in just seconds. Learn more about our laser scanning services here.
How long does a land survey take?
The length of time it takes to deliver a topographical survey depends on the area to be covered and the datasets acquired. Surveys that cover a small area over easy ground surfaces may typically be completed in just one day, while larger areas with greater levels of detail may take up to several weeks.
Different phases of the project lead to different requirements for speed and accuracy depending on the needs of each individual project. Because every site is different, there's no specific answer to the question of how long a topographical survey takes. If you're looking to understand timescales for your land survey project, get in touch to discuss.
What are the data outputs from a topographic survey?
Depending on the datasets acquired as part of the survey, topographic survey data can be output in a range of formats including GIS and CAD format, Digital Terrain Models and Digital Elevation Models (DTM/DEM), imagery and photogrammetry, Point cloud data and 3D models, Virtual Reality and Augmented Reality (AR/VR) as well as Environment Agency formats.
How much does a topographical survey cost?
The cost of a topographical survey is driven by the precision, detail and scale of information that you would require on your survey. We'd be happy to discuss your needs and provide you with a free, no-obligation quote.
Get a topographic survey quote
To learn more about our topographical survey services or to get a quote, contact our friendly team.