Siltbuster has been working with Mott MacDonald Bentley (MMB) to treat the flush waters that were generated during the construction of new groundwater abstraction boreholes at Severn Trent’s Dimmingsdale Pumping Station, ensuring continuous supply for local people and protecting the nearby watercourse.
MMB – a joint venture between Mott MacDonald and JN Bentley – was appointed by Severn Trent to install several new groundwater abstraction boreholes, which meant that the existing boreholes needed to be temporarily taken out of service. Drilling for the new boreholes meant that the underlying aquifer was disturbed, releasing clay into the water, which turned the previously clear, solids free water, an orange/brown colour. To resume pumping the original boreholes needed to be flushed before they could function effectively again.
With 50,000 homes and businesses dependent on the water supply, Severn Trent needed a quick solution. With space on site limited, Siltbuster designed a system from modular kit in its hire fleet, saving both time and space. Within just four weeks, the boreholes were back online pumping high-quality water to the reservoir and in turn the local people. In this time it saved £120,000 in tankering costs and protected the local area from the considerable disruption the associated vehicle movements would have caused. The cost saving is on top of the additional costs and damages that would have been associated with further delays to getting the abstraction boreholes back online. The water was treated on site instead and then discharged to the adjacent canal under consent.
The unique system comprised of self-contained dosing containers, two chemical reaction tanks and eight lamella clarifier units. This was designed to remove the clay sized particles from suspension and achieve a discharge criteria of <60mg/l at an extremely high flow rate of 480 m3/hr. Siltbuster also fitted the system with inlet and discharge monitoring, so that it could be viewed on its newly launched online, real-time water quality monitoring and reporting system, ‘Clarity’. This service gives site managers greater assurances over the water they are discharging and ensures all compliance criteria are met and exceeded.
Richard Coulton, General Manager at Siltbuster, said: “This project played right into our strengths. We were responsive and flexible in terms of our design and manufacture, and quick, with systems onsite within a week. These are areas we excel in and part of the reason MMB selected us. We were also pleased to be able to get the project on to our new real-time monitoring system, Clarity, providing our customers with greater peace of mind when monitoring environmental performance remotely.”
Rob Boniface, Site Manager at MMB, commented: “Credit where credit is due, the kit has worked exactly as required, the Siltbuster team has performed excellently and have pulled out all the stops to deliver us a solution as quickly as possible. We do appreciate all of the hard work and would obviously be keen to work with them again on other projects.”