Events & Courses

Course overview

Excavations, shafts and tunnels which extend to below the standing groundwater level in water bearing soil or rock require a strategy to control water ingress and maintain stability during construction. This is typically achieved either by pumping, referred to as dewatering, or exclusion techniques which may be used separately or in combination. The most used dewatering systems include sump pumps, wellpoints, deepwells, ejector systems and passive relief drains. Exclusion techniques, for example secant piles, frequently combine structural support with restrictions to groundwater flow and may subsequently be incorporated as part of the permanent finished structure. 

Other exclusion systems, such as steel sheet piles, provide excavation support but may then be removed thereby avoiding long term restrictions on groundwater flow. In all situations any failure to adequately control groundwater will result in delay, cost overruns and occasionally catastrophic failure. While the fundamental principles have not changed the methodology has evolved over the last 100 years due to; improvements in materials, plant and technology; improved design methods and monitoring data; the demand for bigger, deeper and more complex underground spaces particularly for infrastructure in urban settings; a tightening regulatory regime; and the ever present need to reduce cost, construction time and risk. 

Over the last 30 years, the need to protect water resources and groundwater dependent environmental features, together with the potential for adverse off-site impacts and flood risk concerns has led to increased oversite and regulation of well installation, groundwater pumping and off-site discharges. This has in turn led to an increased need for hydrogeological investigations, including pumping tests, to more accurately assess flow rates, potential off-site impacts and the effectiveness of any mitigation measures required. 

The regulatory regime varies nationally and sometimes locally, subject to the scale of the works and the perceived risks in the particular hydro-geological, environmental and socio-economic setting. Treatment of the abstracted groundwater may be required prior to discharge. Groundwater pumping systems have low greenhouse gas (GHG) emissions particularly compared to physical exclusion techniques which incorporate cement or steel, and which may permanently impede groundwater flow if not removed in the course of construction. As a result, there can be tension between minimising GHG emissions on the one hand and short-term environmental protection and construction risk on the other. 

Each module will make extensive use of the practical experience of the presenters together with case studies from around the world.

Who is this course aimed at?

The course is aimed at Hydrogeologists, Engineering Geologists and Construction Professionals and should be of interest to both graduates and chartered fellows looking to enhance their knowledge. The course would be relevant to contractors, consultants and regulators who require knowledge of groundwater control techniques.

Learning objectives

Module 3

Understand the purpose of undertaking a pumping test, methods of analysis and the factors which control pumping test design. Recognise the need for environmental protection and regulatory compliance as drivers for the development of a groundwater control strategy.

Programme

This module will be taking place on 30 April 2025 at 09:00 BST, and will last for approximately 1.5 hours, depending on audience participation.

Speaker

Dr Gary Holmes, FGS

Gary Holmes interests are in contracting and consultancy in geotechnical engineering & hydrogeology specialising in construction dewatering, ground source energy systems, groundwater remediation, pumping test interpretation and numerical modelling. Gary is Chief Technical Officer for the international dewatering contractor WJ Groundwater Ltd with responsibility for the management and development of WJ’s engineering and technical operations. This includes remediation, instrumentation and monitoring, ground source energy systems, thermal response testing, pumping tests and dewatering system design in Europe, Canada, the Middle East and the Philippines. Gary is a Fellow of the Geological Society.

Location

This course will be delivered virtually via Zoom. Joining details will be sent out the day prior, alongside any course materials that may be needed.

Fees (including early-bird rate)

* Early-bird discount applicable for all registrations until 1 March 2025. Simply select your delegate type on the registration form and the discount will be applied and reflected in the payment section at the bottom of the registration form.*

Group Discounts

We offer competitive group discounts on all Training Courses:
5 – 9 delegates: 20% off
10 – 14 delegates: 25% off
15 delegates or more: 30% off

For more information on how to access the Group Discount, please email [email protected]

Concessions

We offer students a generous discount. Please verify your student status by either registering with your student email address, or uploading a photograph of your student identification/acceptance letter.

The Society offers a limited number of concessionary rates for those in financial hardship. Contact [email protected] (Please note you may be required to provide details/evidence to support your application for this.)

If you require an invoice to register for this course, please email [email protected]

Registration will close 24 hours before the event takes place.

This module forms part of a six module course series. If you prefer to register for the entire course series, click on the following link:

Groundwater control for construction - All Modules

GSL reserves the right to postpone or cancel a Training Course in the event of low interest. In this instance, a full refund will be offered for registration fees.