OGI Groundwater Specialists Ltd are a UK based consultancy company who specialize in the design of groundwater control systems for the construction industry. OGI design innovative solutions for the most challenging groundwater problems in the UK and globally. They utilize groundwater flow models, geotechnical engineering concepts and site presence to design and optimise the most efficient groundwater control systems in the industry.
The groundwater management and dewatering undertaken for the Littleborough Culvert project was a exceptionally well planned and executed despite the technical challenges and very strict timescales involved. Working in close proximity to a live railway line, the dewatering had to be well designed in advance and then managed during the system commissioning and operation. OGI undertook groundwater modelling of the system during the design phase to ensure the risk of perched water would be minimised at the centre of the railway embankment when excavation commenced. The modelling resulted in OGI placing wells along the Network Rail boundary fence parallel to the railway. Settlement of the live railway was also a major risk because of the compressible soils beneath the site. OGI implemented an innovative system start up procedure where the wells were slowly brought on whilst the water level and railway line were closely monitored. The dewatering performed perfectly resulting in a very dry, safe and stable working environment. This meant during the 4-day railway blockade there were no delays due to difficult working conditions and the railway returned to being operational at the end of the blockade as scheduled.