A North Wales-based engineering, environmental and planning consultancy has utilised its expertise to play a key role in reducing the input of sediment and nutrients on a stretch of the River Dee.
Caulmert, which has offices in St Asaph, Bangor, Altrincham, Nottingham, and Kent, has been working for Natural Resources Wales (NRW) to plan and design a bridge across the Little Dee in Penaran Forest as part of the LIFE Dee River programme.
The scheme aims to restore the river’s health and habitats, and the addition of a bridge at the crossing in the Penaran forestry block will have a positive impact on nature in the area.
Prior to installation, forestry vehicles had to cross the river by driving directly through the watercourse, leading to contamination and the potential to harm spawning grounds of fish and other aquatic animals further downstream.
The new crossing will prevent an estimated 4,000 trips through the river by articulated lorries, with approximately 25,000 tonnes of timber to be harvested and transported over the next five years.
The bridge measures 8.5 metres long and 3.5 metres wide and construction included the use of 10 precast concrete planks for the deck.
After spending four months on the project, Caulmert handed over the plans to NRW to start the build.
Caulmert associate director Peter Dawson, who oversaw a team of three at the design development stage, said: “It was wonderful to be involved in such an important project for the local environment in Gwynedd.
“It is an unconventional bridge of a fairly short span and will be used infrequently, but it still needs to take the weight of 44-tonne articulated lorries.
“We really thrived on creating the most straightforward yet cost-effective design we could.”
Caulmert also devised the streamlining of the embankment and improvements to the access track leading to and from the new bridge.
Peter continued: “One challenge was to set the bridge level to minimise the risk of flood impact but also reduce the length of reprofiling of the access road that has to tie into the deck level.
“Each concrete plank was slid in from one end of the bridge and there is no concrete topping, so that maintenance inspections can be carried out more efficiently.”
Tomos Wynne, land management officer for the LIFE Dee River project said: “The bridge will help limit the input of sediments and nutrients from entering the watercourse and will also reduce the chances of any further contaminates from entering the Dee, offering benefits to salmon and other aquatic species found there.
“The work forms part of our wider programme to improve conditions throughout the entire Dee catchment, including weir removals, installing riverside fencing, tree planting, and reintroducing boulders back into the river channel.”
Tomos continued: “Working with our contractor, DW Jones, and designer, Caulmert, the plan and build has ensured water quality in the Afon Dyfrdwy, a Llyn Tegid special area of conservation, is protected in the future.”
Founded in 2009, Caulmert is on track to meet an ambitious growth and development plan.
