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What does a GPR survey cost in real terms?

Reading Time: 5 minutes

The UK construction industry is infinitely safer than it was. Within my working life, the strides made are quite staggering. The industry is to be commended for the actions it has taken in protecting the workforce, the benefits, almost unbelievably, are still not adopted universally.

GPR survey teams are used to working in environments where health and safety is the overriding priority. As a utility survey company, that should be part of the DNA. It has to be, because the standards the clients would accept are so high. That is a good thing.

The changes introduced do not just provide health and safety benefits. An example of this is the mandatory PPE expectations. This includes high visibility tops where long sleeves are mandatory, high visibility trousers, protective glasses, gloves which are suitable for the task and a hard hat with a chin strap.

Adopting the mandatory requirements of some of clients on a wholesale basis has the additional benefit of the look of professionalism when a survey team turn up to a location all kitted out correctly. I still see survey teams from other companies wearing a pair of jeans and a high visibility vest. It doesn’t look great.

Visualisation of Cost

Despite the strides made in all areas of health and safety culture, I encounter on a day to day basis the metaphorical raised eyebrows when discussing GPR survey cost. It seems that the relationship between health and safety, cost and value has not permeated the utility surveying sector.

I understand this. For many applications within the industry, the benefits of a particular service provider are quite clear. For example, the costs associated with laying 100m of ducting across a car park can be easily understood and can be visualised. Simply put, the different method used for a utility survey are not well communicated throughout industry.

The cost of a GPR survey is not quite as straightforward. I will explain this momentarily, but let’s talk about value first.

The Cost of Service Strikes

There are around 1.5 million KM of buried utility infrastructure in the UK. Excavations take place approximately 10,000 times on a day to day basis. The Utility Strike Avoidance Group publishes a report annually. The members report service strikes in an attempt to collate some real-world figures on the cost of these events.

The most recent figures from 2017-2018 reported around 3000 service strikes. The direct cost of which was estimated at £7million. The true number of service strikes go unreported,  but it is estimated at around 60,000 per year. Extrapolating the cost from the reported ones we have a direct cost figure which is a quite staggering £140 million.

This does not include any indirect and social costs. Let alone the fundamental health and safety implications associated with service strikes. The USAG report estimates the indirect costs as 29 times direct. The numbers are simply mind-blowing.

Based on this, it is no wonder leading contractors make utility strike avoidance an extremely high priority.

A good underground utility survey reduces the risks of excavating around services infinitely. Even over and above just the procurement of service records. A GPR survey cost is not an insignificant amount. The value it adds in terms of the risk reduction and in comparison to the indirect costs of a service strike are incalculable.

If the USAG figures are accurate a single service strike has a cost of over £100,000. When you consider this against the GPR survey cost, the value of a survey becomes quite clear.

Not all utility surveys are equal. This is where the complications begin

Most buyers still use cost as the main metric when placing an order for a survey. They will go out to the market place and receive a series of quotations for the work. This is most stark when public sector buyers publish the outcome of a tender process after the award of a contract. The lowest bids, which normally are the successful ones, are often extraordinary based on the works being tendered.

A tender recently I was recently working on, had a range of GPR survey costs submitted. These were mostly between 12k and 19k. The winning bidder submitted a price around the 5k area. The difference was quite stark.

It may be that the service provider in question is able to deliver a survey to the same specification as the other bidders, for a significantly reduced cost. This may sound like sour grapes. It is not. I have no issues with losing tenders in a competitive marketplace. That is how the client ensures value. This article is to highlight the differences in the GPR survey cost how they affect the outputs being received by the client.

As a client receiving GPR survey cost estimates, it is important for you to understand the differences between each provider.


The specification which is the best practice currently within the underground utility survey industry is PAS 128 in the UK. It is different in other parts of the world. For instance in the USA it is ACE Standard 38-02 and in Canada it is CSA Standard S250. Certainly speaking from a UK perspective, PAS is not fully understood at the client level. Many buyers have not had sufficient training to understand the varying survey levels available. Without this training, someone procuring a survey may not know the difference between, for example, an M2 or M3P. Additionally, unless specifically asked, the quotation may not disclose the survey level. The buyer will just see the cost. Based on the information available, they will quite rightly award the work to the company with the lowest cost tender.

Even the difference between an M3 and M3P makes a significant difference to a GPR survey cost. The P designates that post-processing has been undertaken. The operator has marked the GPR on-site if there is no P. Not every survey provider has the in house capability of post-processing GPR data. These differences could be thousands of pounds on some projects. Although not every survey needs to be post-processed, the value it adds to most projects outweighs the additional cost.


There are no mandatory training requirements for utility surveyors to be able to practice in the UK as the industry is unregulated. There are QCF qualifications that surveyors can and should undertake. Starting with level 2 and ending with level 6. Most senior surveyors should have a level 5 and surveyors a minimum of level 3.

The level 2 qualification is a particularly interesting one as it explains the theory of circular fields in great detail. The training shows the surveyor how to correctly use the equipment and how to ensure the signal they are following is the correct one. An essential skill for anybody who uses electromagnetic tracing techniques.


The type of utility survey equipment being used by a survey provider will also directly affect a GPR survey cost. There are now a huge array of choices of GPR on the market. These range from basic units designed purely to mark on site and go up to highly technical high density arrays. 

A provider who is quoting for a job without the post-processing of GPR may not have the equipment to collect the data in a way in which it can be processed. This doesn’t take into account the skillset and expensive software required for the task.

The point is, the GPR survey cost is affected by many elements which may be technical, human or specification. As a buyer, unless you specifically request a certain level of survey, the prices you receive may not be comparable.

A survey practitioner should always make it clear what level of survey they will be providing and itemise what is going to be included. This approach leaves clients with no ambiguity as to the specification of the survey and the level of detail they can expect.

It is the job of the survey practitioners, like us, to provide the clients with the information they need to make informed purchasing decisions. That information should include the limitations associated with a GPR survey, such as effective penetration depth of GPR equipment, based on factors such as soil type and moisture content.

Armed with relevant data and comprehensive surveys which are relevant to the environment they are being undertaken, we can all work together to reduce the service strike statistics in the industry.

Andrew Botterill