Geotechnical people are in the habit of using terms like village and community to describe their industry, which conjures up images of smallness and cosiness. There is a wide-spread view within industry that geotechnics is a tiny sector of the civil engineering industry employing a few thousand specialists.
But look around and it is clear the geotechnical community is much bigger and less of a niche than those within it believe. It is also the reason it should be given more attention. There is plenty of scattered evidence to support this claim, but unfortunately there is no single definitive source. Just sit at the back of the hall in the Rankine Lecture and look around. According to perceived wisdom, the 700 plus in the hall represent maybe a fifth of the UK geotechnical sector. Look closely and you may see a cluster of say three senior faces from a company that you know employs 40 geotechnical engineers - yes, it is an exceptional turnout, but not more than a tenth of community.
In trying to put real numbers together the Institution of Civil Engineers is a good starting point. ICE used to collect information on its members' main professional interests. Between 1989 and 1993 a consistent 17-19% of ICE members identified geotechnics as their primary interest. ICE's membership is about 65,000. Removing students and retired members leaves about 40,000 engineers active in the workplace - and 18% of 40,000 is 7200.
ICE changed the way it collected information on its members in the mid-1990s and the most recent census from 1997 (new figures are due out imminently) breaks activities into smaller divisions and lists primary and secondary interests, making interpretation harder. Nevertheless it is fair to assume there has not been a major shift in the number of geotechnical engineers.
ICE membership appears to be a fairly representative measure of the geotechnical engineering sector. In a recent straw poll of contractors and consultants conducted by GE a high proportion of geotechnical engineers (80-90%) within the companies polled were ICE members of some grade. Of course not all professionals active in the industry are ICE members. In particular the Engineering Group of the Geological Society lays claim to a further 2500, although depending on where you draw the line between applied geology and engineering geology there is an argument that 3000 is a more representative figure. We perhaps reach the magic figure of 10,000 engineer grade employees within the UK geotechnical sector- about three times higher than the figures usually quoted.
Taking another approach, the British Geotechnical Society has about 1250 members. Our straw poll revealed that within specialist geotechnical contractors only 5-20% were BGS members. These are essentially the design teams plus some of the more senior operations people. Of course we found exceptions to these figures, especially among companies who employed active members of the BGS committee!
Among consultants the proportion is higher - 20-40% of geotechnical/geoenvironmental consultants were BGS members. Very crudely, probably less than a fifth of the industry is signed up to the BGS - suggesting the imminent formation of the BGA is a great opportunity to strengthen the community.
Taking another tack, before Ground Engineering was distributed to every member of the British Geotechnical Society, we had about 1500 subscribers in the UK. When I worked as a graduate engineer in a consultancy I was about tenth on the circulation list for GE. More reliably, Ground Engineering has well researched and representative data from this time that each copy was read on average by 5.7 engineers in the UK. That puts the number of professionally interested readers at about 8500.
Ground Engineering publishes an annual Geotechnical Services File, which covers both consulting and contracting services. Our 2000 edition will be published next month and it identifies nearly 6500 'geo-engineers'.
Our database includes about 750 companies and this year we have secured responses from nearly 400. We have made sure we have responses from as many of the main players as possible and are confident the file is sound and representative (but short of turning up and handcuffing ourselves to the reception desks of some companies we cannot elicit responses from some - funny how suspicious people are of free publicity and marketing).
Criteria for entry in the editorial file is that you must employ at least one geo-engineer. Many of these missing companies may have not responded since they knew they would not qualify, but possibly there could be at least a thousand or more engineers out there, lost and unaccounted for. One could go on, but its safe to assume there are a minimum of 8000 and perhaps 10,000 geo-engineers out there.
When totting up the size of the industry there is also the issue of who to count. The figures above mostly identify engineer grade individuals within practice. But what of the significant academic community, or technician grade staff, or technical sales staff, who are all contributing to the business of geotechnical engineering?
Extending this line of thought and by including site operatives with specific geotechnical skills, such as drillers and piling operatives, and the industry as a significant UK employer mushrooms. For example, the 20 or so companies in the Federation of Piling Specialists collectively employ about 3200 of whom only a couple of hundred may be engineering grade.
The other big unknown is the industry turnover. The Geotechnical Services File identifies about £800M of geotechnical turnover in the UK, and it is a fair bet that a £1billion estimate on the total market will not be far out. About £400M of this is tied up in the piling and foundation contractors, while New Civil Engineer's current Consultants File identifies about £100M fees rendered among the top 50 geotechnical consultants, and a further £250M fees rendered by environmental consultants, a sizeable chunk of which will be within the geotechnical/geoenvironmental sector.
It's shaping up to be a pretty big niche.