Reduced Impact on the Environment – River Protection

Following on from our recent post about Geobear’s environmentally friendly solutions, Bruno D’Arcy discusses the low environmental impact of our solution on a recent project completed in Scotland.

A section of river bank along Leacann Water was weakened by severe undercutting, or scouring. A voided area 30 metres in length at the base of a retaining wall had been discovered which, if left unchecked, would have threatened the integrity of the road above, the only means of access to the nearby village of Furnace.

The river bank along Leacann Water

The Principal Contractor, Bear Scotland, was looking for a cost effective environmentally friendly solution. Whatever scheme they submitted to Transport Scotland, the client, would have to undergo close scrutiny from the Scottish Environmental Protection Agency, so it was highly unlikely that traditional methods such as cementitious grouting would not be acceptable. It was acknowledged that under no circumstances would contamination to the river be permitted. If no suitable scheme could be found, the client was even prepared to allow the river to be temporarily diverted while a less environmentally friendly repair was carried out.

Geobear had worked for Bear Scotland before and they requested we submit a proposal using our ground injection method as an environmentally secure way to fill the void and stabilise the area. Following the proposal submission we conducted a successful trial that confirmed the suitability of our method.

COSHH assessments and Safety Data Sheets were sent for the client’s scrutiny in advance. These clarified that the cured Geobear materials are not hazardous to aquatic life, do not contaminate soils, and can be installed with minimal disruption to the local ecosystem, animal habitats included.

Despite the non hazardous nature of the materials, extra precautions were taken when carrying out the project to prevent any residues escaping. Netting was stretched across the banks and personnel were on hand to remove any stray material from the water: the river was quite shallow and the material floats, so in situations like this it is not difficult to remove.

Careful planning beforehand (the base of the retaining wall was shuttered off), ensured the project could be completed within two days and was pronounced a complete success by Bear Scotland. None of the Geobear material entered the river and the local ecosystem was left undisturbed. The void was filled, and the scouring to the base of the retaining wall has been arrested.

Geobear has often been chosen to carry out such projects. As recently as 2017 Geobear carried out two void filling and scouring protection projects in Cumbria. Both were to stone constructed bridges near Kendal, where relentless flood waters had severely damaged bridge supports.

Again, one of the main reasons for choosing Geobear was because of the non hazardous nature of the materials. Full protective measures will always be put in place when working near water courses, but it’s still comforting to know that if any material accidentally gets into the river, for the brief amount of time it is in the water before it is removed, it is highly unlikely to cause harm.