A Farming in Protected Landscapes funded project in the Tamar Valley National Landscape tackled surface water runoff threatening a Scheduled Monument and the wider river environment – while improving soil health and habitat diversity on the farm.
Deer Park Farm is a 113-hectare mixed farm in the lower Tamar Valley, its land sloping from the edge of Kit Hill Country Park down towards the village of Luckett and the River Tamar. The farm has arable fields, permanent pasture, ponds and woodland – but its topography was creating a serious problem. Surface water was running rapidly down the farm lane, through field gateways and across compacted ground, gathering speed and energy before passing through the adjacent New Consuls mine site and into the Luckett Stream.
New Consuls is a nineteenth to mid-twentieth century mine that produced copper, lead, silver, arsenic, tin and small quantities of gold. The entire site is a Scheduled Monument, and several exposed metalloid spoil heaps had been eroding during peak rainfall events. This presented a twofold problem: the protected historic features were being damaged, and the material washing off them was contaminating the Luckett Stream and, by extension, the Tamar Estuary. The Tamar Valley National Landscape team allocated £5,485 from FiPL and £6,750 in match-funding from the Heritage Lottery Funded Tamara Landscape Partnership, to address these issues at source – a total of £12,235.
Understanding the problem
First of all, the team at Deer Park Farm commissioned David Thomas to map the key flow-paths at the farm and New Consuls, identifying which routes most directly contributed to erosion and contamination downstream. They used the results of the survey to design a package of interventions following the principles of natural flood management – using natural timbers harvested on site to slow water flows, de-energise erosional forces, and allow sediments and pollutants to settle out before reaching the stream.
Interventions on the farm and at the mine
At Deer Park Farm, South West Natural Solutions Ltd put in place a range of measures to intercept and slow the flow. Existing ditches and flow-paths were converted into swales (wide, shallow depressions) with flow disruptors to slow movement and store water in a slow-release system. They created earth bunds and scrapes to hold water and capture sediment, and new earth banks planted with hedges to intercept surface flows and improve infiltration through their root structures. They relocated a gateway that had been channelling water at maximum flow energy to reduce the sediment and nutrients washed off at peak rainfall. Finally, they installed ten leaky dams and brash bundles to slow flows within the existing flow-path and put in place 110 metres of protective fencing to exclude livestock from the most sensitive areas.
At New Consuls, the team constructed dense dead hedges from material harvested on site during coppicing work. These are placed close to the ground to intercept overland flows where sediment is being mobilised, capturing leaf litter and organic debris and becoming more effective over time. Logs are now staked in place to hold high flows back and allow sediment to settle before water enters the Luckett Stream. They also installed three scrapes with constructed spill points and a swale with check dams as part of the wider scheme.
Benefits for farm, heritage and river
The project has delivered benefits that reach well beyond the farm boundary. By slowing and intercepting runoff, the work is keeping soil and nutrients in the fields where they can support grass, crops and livestock, while improving infiltration and promoting livestock health. The reduced flow of metalloid-laden sediment from the mine site is protecting both a nationally important Scheduled Monument and the freshwater and saline environments downstream.
Deer Park Farm’s membership of the Stoke Climsland Farm Cluster and its role as a Nodal Farm for the Tamara Landscape Project means the lessons learned here can be shared widely with the broader farming community. The farm’s established educational access programme will also be further developed, extending its offer to schools and other interest groups. The project is part of a wider commitment on the farm to adapt its business model to the challenges of climate resilience and carbon neutrality.
Martin Howlett, Farmer at Deer Park Farm said:
“Targeted FiPL funding to help address nature recovery and climate change here in the Tamar Valley has encouraged us to go the extra mile, beyond traditional farm management, delivering ‘Slow the Flow’ projects that improve soil health, reduce run-off and create better habitats for wildlife and people.”
