Aquamaintain Ltd was asked to design and construct a scheme to return an urban pond in Surrey to favourable conditions. The pond was suffering from high degrees of pollution and sedimentation from road runoff, this impacted water quality, resulting in dangerous conditions and frequent algal blooms. In addition to this habitat had been lost around the pond, which had seriously reduced the site’s biodiversity.
Scope of the Project
Due to the sites difficult urban location, a methodology had to be devised to improve the site’s features with the minimum impact to the pond’s surroundings. In addition, sediment could not be removed from the site owing to its hazardous nature from the road runoff and the high costs in disposing of it.
A scheme was proposed that utilised the pond dredging’s retained behind a natural fascine. This created a wetland marginal zone, which introduced habitat, covered the ponds hard concrete edge and intercepted polluting road runoff before it entered the pond.
The project involved the use of specialist machinery in the form of a long reach excavator positioned on a floating pontoon.
This enabled us to dredge the pond effectively without the need to drain it, reducing the impact on the pond and its surroundings and reducing the overall project costs.