Welcoming CIRIA C750

Ciria Groundwater ControlThe second edition of the much-used best practice guidance (replacing CIRIA C515 probably the de facto CoP for groundwater control in the UK and Ireland) is a welcome addition to the library here at AGEC. Aside from addressing the many typos of the first edition, the main changes are to Health & Safety and Environmental regulatory practice.

In terms of the available literature, we also like “Groundwater Lowering in Construction” by Cashman and Preene. Now in its second edition, it has a level of detail that C750 or its predecessor C515 doesn’t have.

That being said, we still keep S.H. Somerville’s classic CIRIA R113 “Control of groundwater for temporary works” from 1986 around – it is still mandatory reading for young geotechnical engineers and has a level of usefulness for designers that, sadly, modern good practice guidance seems to be lacking.

Another plus for C750 is more case histories (14 versus 9 in the first edition) though, in our opinion, there still aren’t enough. Groundwater control in projects can be very difficult to design and implement properly. Practitioners will say that experience still counts above all were groundwater control is concerned – as Arthur Casagrande said: “Water has a way of seeping between any two theories!”. Precedent and case histories provide the most useful basis for scoping of dewatering schemes. One of our favourite collections in the AGEC library is the proceedings from the ISSMGE conference on groundwater held in Dublin in 1987 – almost 30 years old but still a collection of good quality case histories and academic papers.

At AGEC we have a good pedigree in groundwater control projects, most recently acting as third party checker on the Raith Interchange, part of the M8/M74 widening scheme in Glasgow for the Ferrovial-Lagan Joint Venture – a phased scheme comprising over 20 dewatering wells and anticipated cumulative abstraction rates of over 120l/s.