Business News

World-First ‘Mermaid’ Provides Innovative Solution In Scour Protection Project



Construction business Osborne and sub contractor Suttle Projects recently collaborated together to provide a world-first scour protection solution. The river bed needed to be dug out and replaced at the River Colne, near Staines in Surrey. Due to deep, fast flowing water and low headroom of the bridge, traditional sheet piling techniques were not viable. Therefore Osborne worked in partnership with Suttle Projects to overcome the problem by using its bespoke underwater remote control excavator nicknamed ‘The Mermaid’ for the first time commercially, believed to be the only one of its type to exist globally.
Working underwater brings a number of hazards and challenges, but Osborne worked with Suttle Projects to develop their own innovative solution. The mermaid was deployed, a remote-controlled fully-submersible digger, that scooped out the existing river bed. Divers then set out grout bags – which had to be hand-placed underwater and layered to the right levels. Finally silt could be laid over the top of the hardened grout bags.

In the case of the Staines bridge, the headroom was far too low for a standard mini excavator to be used on a pontoon with an operative sitting in the cabin to work it. In addition, the water was too deep to over pump the channel or divert flow to create a temporary dry work environment. Therefore, the mermaid was deployed, situated on a floating pontoon to carry out the scour protection work. Its lower height of 0.8 metres tall versus the standard height of around 2.7 metres meant it was able to work effectively under the bridge, and was safely activated a few metres away by an operative managing the remote control unit.

The mermaid took 18 months to build in-house by converting a conventional mini excavator, with the project costing £65,000 overall. This was done by removing the cabin and engine and adding remote controls. The remote control unit was connected via hydraulic umbilical leads, supplying the machine with hydraulic power. It works on a hydraulic pressure of around 150 bar, with a flow rate of 25-50 litres per minute, weighing 4 tonnes. The mermaid is currently set up to work underwater up to 25m deep, but can easily be set up for deeper water conditions if required.

Paul Fagan, Osborne Site Manager, said: “The use of this self-developed technology simplified a complex operation, significantly reducing the time divers had to spend in the water. We are delighted with the outcome of this project and always look to new technology and better ways to deliver results.”

Director of Suttle Projects, Joe Paine, added ‘On a previous scour protection project with extremely heavy rainfall and a very low railway bridge, we used divers to place concrete, and also had to excavate with a type of venturi water suction pipe, suspended from our pontoon. Although this did provide a solution, it was time consuming and costly. We soon realised that a conventional small excavator that was able to work freely under water would provide the ideal, innovative solution. We could find nothing of this type on the market globally, so with support from Ross Welsh at Pirtek Poole, who specialise in fluid transfer solutions, we decided to build our own machine, the mermaid, which we can also hire out to other companies, too. By collaborating with Osborne to use this equipment in the project, we were able to provide an efficient and cost-effective solution for what was historically a complicated and expensive task.’

Osborne is one of the leading construction businesses in the UK. As a family-owned business, we have the freedom and flexibility to take a different approach. We focus on creating structures and spaces that provide an environment for people to thrive in, and solutions for our customers that provide a better experience during the creation. From rail to road, housing to healthcare, however large the project or contract, we know that it is always personal to the people who use it and those that are responsible for it.


Introducing our newly appointed Sales Director


Introducing our newly appointed Sales Director, Dave Penney. Dave has been with Suttles for 7 years now as our sales…

Read More ›

Swanworth Quarry Celebrates a Centenary


Swanworth Quarry in Worth Matravers, owned by Suttle Stone Quarries, is celebrating its 100th anniversary. The quarry currently supplies approximately…

Read More ›

Health & Safety Recognition from the MPA


Suttle Stone Quarries are members of the MPA – Mineral Products Association – a trade body for our industry with…

Read More ›

Suttle Projects Win Award at Inspiring Change Awards 2021


In November we were shortlisted for the ‘Inspiring Change – SME Award’; This award seeks to recognise businesses that have…

Read More ›

School Visit to Swanworth Quarry


Yesterday Simon, our Director of Quarrying, took a school group of year 7 geography students on a tour of Swanworth…

Read More ›

Second Phase of Groyne Renewal is Underway


The Bournemouth Echo have spotted us, have you?   The first phase, which was to remove 5 existing timber groynes…

Read More ›