The parklands were an early example of Picturesque ideals being utilised in landscape design, characterised by the contrasts that nature can show – at one moment, beautiful tranquillity, and at the next the drama of tumbling water over cascades, a weir, and waterfall. We have access to six of the fifteen paintings by Thomas Hornor who was invited by William Paxton to paint a series of viewpoints throughout the estate in 1815. The intricate details in these paintings of the parkland and lakes have provided the designers and engineers with a wealth of information on which plans for the restoration were based.
Over the last two and a half years, the restoration site has been a hive of activity. The very warm summer of 2018 bore witness to large machines undertaking the mammoth task of removing 22,000m3 of silt from Llyn Mawr which had built up over the preceding decades. Clay was then extracted from borrow pits within the adjacent fields to create the dam and this was compacted with a machine called a pad foot or sheep’s foot roller. During Paxton’s time, this compaction would have been carried out by families using wheelbarrows and flocks of sheep – hence the modern machine’s name. Each layer of compaction was tested with geotechnical tools, to ensure the dam would meet stringent Reservoir Act requirements. Llyn Mawr is one of the largest lakes at the Botanic Garden – over 65,000m3 in size, that’s nearly three times bigger than the existing lakes combined! The dam is 350m long and has three spillways to take water over the dam. Spillway one is used in everyday conditions, while the other two are engineered to cope with bigger floods.
There are six bridges in total which link up and provide a series of walking circuits which snake through the landscape. The two steel bridges fabricated in Swansea by Afon Engineering were craned into place in August 2019. Two bridges were recently installed and the last two will be in place within the next two weeks which completes the network of bridges which link up the landscape.
The contractors Longreach are in their final few weeks of construction. Once we have completed all our finishing touches, we will open up the restored site later this autumn and we really can’t wait!