Ace Penstock Protects Homes In Lydney - 9th February 2015

There has been a ‘significant risk’ of flooding associated with the historic port town of Lydney over many years, as it is an associated with the River Severn Tidal Estuary and located at the bottom of a catchment which is susceptible to changes in water level. In 2007 flooding reached its pinnacle when high water levels brought misery to the small community. Whilst the Environment Agency has provided a Flood Alleviation Scheme increasing the level of protection from the Tidal Estuary and main River Lyd, there has still been a significant risk of flooding from a number of other critical ordinary watercourses which flow into Lydney from the upper catchment. This can be further exacerbated when a tide locked scenario occurs. With prolonged spells of localised rainfall, these watercourses fill quickly, and, unable to discharge into the tidal estuary, they can contribute to the flooding of properties within the built up residential areas of Lydney. The Forest of Dean Council contacted ACE to discuss water flow control ideas for a particular watercourse originating upstream of Lydney which had historically been linked with flooding of property downstream. ACE was able to offer a 1.2m penstock and fill any gaps, to alleviate the risk of flooding downstream by helping to control and attenuate the water upstream of the main A48 Lydney Bypass. By installing this penstock upstream of the road, culvert water could be held back in this low flood consequence area when Lydney was subjected to the risk of flooding. When mounting the penstock a small channel was dug out to allow it to be recessed into the ground. This meant the penstock opening was flush with the base of the channel so no water or silt could build up in the culvert. Within a few weeks of installation, the penstock was being put to the test as water levels rose to potentially dangerous levels completely immersing the penstocks door; however the penstock was successful in reducing the flow of water to a level that could be transported by the drainage network. By providing this low cost sustainable level of control with low maintenance solution, ACE has been able to contribute towards the Forest of Dean Councils overall efforts in reducing the risk of flooding to the residents of Lydney. ACE would like to thank Forest of Dean District Council and the residents of Lyndey for helping make this project a success.