Wet civil engineering specialist Land & Water was awarded the contract to construct a new hydropower station at Caversham Weir, Reading, on behalf of Reading Hydro CBS Ltd. The £1m project is designed to harness the power of the River Thames using low-head hydro turbines, creating a renewable source of energy to the National Grid.
The project included the installation of watertight cofferdams in the Thames, and for this Land & Water called upon Selwood’s pumping solutions specialists for support with overpumping.
The cofferdams were constructed in an area where there was plant equipment on site and a limited amount of space for the pumps to be installed in.
There were also the site’s natural woodland surroundings to consider, and the need to provide an environmentally-friendly solution to pump fluid back into the Thames using a setup that would drain the area quickly but safely.
Selwood’s solutions teams visited the site to carry out a detailed survey and make calculations for the best setup for the job. Their recommendation was for two pumping setups, using Selwood six-inch D150 drainer pumps positioned in pairs on each side of the dammed area.
One side was configured as a duty and standby setup, with the other as a duty and assist. The pumps were supplied with auto start/stop systems.
Silt traps were supplied to minimise the amount of solid material being pumped back into the river. As a precaution, Selwood’s teams also installed submersible pumps that could be used in the event of water entering the working area over the top of the dam, although due to the high quality of the dam these were not required.
The Selwood’s ability to act quickly and thoroughly from site survey to quote stage gave the customer time to plan ahead of the project’s start date. The auto stop/start function of the pumps minimised fuel consumption by ensuring the pumps were only running when needed.
The effectiveness of the solution resulted in the areas draining more quickly than had been anticipated, helping the project stay on track for completion on schedule.
Land & Water reported that they were extremely pleased with how quickly the pumps drained the area, and as a result the customer was able to take one of the pumps off hire sooner than planned, with a cost saving as a result.