Milestone As Edinburgh Team Pulls Enormous Nine-Tonne Screw Pump To Surface

“A lot of work goes in to planning the removal of underground assets. Thanks to their dedication and hard work, our team was able to complete this challenging operation successfully, setting us up for the next stage of the refurbishment of this important project.”

William Moore 
Project Manager, Scottish Water 

A multimillion-pound project in Edinburgh has taken a significant step forward, following the removal of a nine-tonne screw pump from underneath the ground as part of the ongoing upgrade of McDonald Road Waste Water Pumping Station.

The underground pumping station uses enormous Archimedean screw pumps to move millions of litres of waste water across the capital. It has been in operation for over 50 years and to ensure the continued efficiency and reliability of the sewer network, the site is undergoing a major refurbishment.

There are two screw pumps under the ground and this phase of work focussed on the removal of the “foul”, or “duty” screw, which is in operation every day to move waste water, collecting drainage and lifting it to a larger sewer which then then runs by gravity to Seafield Waste Water Treatment Works for treatment.

The foul screw is located adjacent to the larger “storm screw”, which operates under storm conditions. The original storm screw was removed in December last year and was replaced with a new one in April 2024.

The removal of the foul screw required careful planning and coordination, due to its weight and size. The screw, which is 8 metres long, was removed by a crane with the teams on site taking extreme care in the difficult conditions. Following its removal, the foul screw will be replaced in the coming weeks.

William Moore, Scottish Water's project manager for the operation, said:

"Removing the foul screw from underneath the ground is a significant step in the refurbishment of McDonald Road Waste Water Pumping Station, reflecting the expertise and dedication of the team.

“A lot of work goes in to planning the removal of underground assets. Thanks to their dedication and hard work, our team was able to complete this challenging operation successfully, setting us up for the next stage of the refurbishment of this important project.”

Many of the assets that keep Edinburgh’s water and waste water cycle running are hidden underground. McDonald Road pumping station is crucial for managing the city's waste water and the refurbishment is to ensure that it can continue to serve the local community and protect the environment for many years to come.

The work is estimated to be completed in early 2025. The project is being delivered alongside delivery partner, Morrison Water Services.