Specialists in Water Management for Landscapes, Fisheries, Leisure and Conservation
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Case Study 2. Liner Installation |
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The earthworks under way |
Client:
Private ClientLocation: Forest of Dean, Gloucestershire
Description of Contract:
Working for a Private Client through the award winning Landscape Architect Tom Stuart Smith we were employed to advise on, and construct a new amenity lake at the edge of the garden as part of a major redevelopment of the property.
The first issue was to identify a suitable water source, whilst there are numerous springs flowing out of the hillside in the winter there was no summer supply. We there fore undertook a hydrogeological desk study of the area with a view to installing a borehole. Because of the soil types encountered the well had to be drilled to 90m deep and lined over most of its length, but it does provide a reliable source of water that will maintain the summer levels in the lake.
It was agreed that the cheapest route would be for the bulk earthworks to be undertaken by a competant local contractor working directly for the Client but under our control. We then supplied, installed and surcharged a 1mm EPDM waterproof membrane protected on both sides by a 700g/m2 protection blanket. As with many schemes once the earthworks had started and the extent of the lake could be seen, so the Client asked for the lake area to increase by 1,600m2 to 4,300m2. We also installed the foundations and piers for a timber boathouse, which included a jetty / diving platform accessing a 4m deep section of the lake.
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The liner being installed around the boathouse and around the jetty leg supports |
Surcharging the liner with a 200mm dressing |
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Now there's something you don't see every day! |
As the lining work neared completion the installation team were horrified to see a microlight aircraft spiralling, out of control towards their work, fortunately (for us) the aircraft managed to rise over the lake side before crashing into a telephone pole 50m away, both pilot and passenger walked away with only cuts and bruises.
To improve water quality and induce some circulation into the lake a 1.1kW flowmaker has been installed on on of the jetty legs, in addition to moving a large volume of water for a small power consumption the unit also draws air from the surface and entrains it into the flow.