HUNDREDS OF thousands of trees will be planted as part of a long-term plan aimed at reducing flood risk in the Calder Valley – which was devastated by the storms of December 2015.
The towns of Todmorden, Hebden Bridge and Mytholmroyd were severely affected when the River Calder burst its banks just over a year ago.
When the Government’s National Flood Resilience Review responded to the inundation last year, community groups in Hebden Bridge called it “shockingly disappointing”, partly because it made virtually no mention of the importance of managing how water drains from the surrounding moorland.
Now Yorkshire Water has announced its long-term Natural Flood Management plan for the Calder Valley which will start with a plan to plant up to 200,000 trees in the next few years.
The moors above Gorpley reservoir, between Todmorden and Bacup, has been identified as a site where tree planting can begin. A 60 hectare area of “species-poor grassland” will be planted with 3,000 trees per hectare by community groups.
A spokesman said other flood management measures would also be implemented on these moors over the next five to 10 years, including restoring sphagnum moss on 43 hectares of blanket bog – a move which he said would help to absorb and slow down rainwater run-off.
The spokesman said Yorkshire Water was also looking at repairing dams on smaller watercourses, strengthening river banks and creating a patchwork of wetland areas on its upland estates.
Granville Davies, manager of asset strategy for Yorkshire Water, said: “The flooding at Christmas 2015 had a devastating impact on communities in the Calder Valley and we fully recognise the responsibility for all agencies involved in flood management to work together to devise innovative solutions to reduce the risk of flooding.
“In addition to contributing to the Calderdale Flood Action Plan, we’re leading Calderdale’s Natural Flood Management Group and working with partners, like the White Rose Forest, to look for innovative ways that we can use our land to slow the flow of water in the upper catchments, evaluating the best places for us to plant trees and build leaky dams, and engaging with other landowners in the area.
“Over the next three or four months we will be working very closely with the White Rose Forest to design a scheme in more detail and come up with some more firm proposals.
“Hopefully over the next four months, through to June, we will be developing the design in more detail.
“We’ve got to do some survey work up there to make sure that we are not interfering with any other sensitive areas of the environment on the slopes.”
It’s hoped the tree planting programme will begin by autumn this year.
Mr Davies said the plan has to be seen as part of wider efforts to reduce the flood risk.
He said: “I think in terms of protecting the Calder Valley into the future, it’s about looking at a whole range of measures.
“I think when we look at the devastating floods in Calderdale in Christmas 2015, clearly with an event of that magnitude, it takes an awful lot to try and reduce that risk going forward.
“So while this is a great thing to do within this landscape and will have some impact here, it really is this being one part of a whole package of measures that need to be implemented across the whole of the district.
“Natural flood management is a part of that, but it’s working alongside more traditional flood defence measures, so the whole range of flood measures complement each other.”
The company is working with the White Rose Forest, which is made up of a number of organisations who aim to plant and manage more woodland to make the region a greener and a healthier place.
Guy Thompson, from the White Rose Forest, added: “Natural flood management is a long-term solution. It’s not going to make changes overnight, but it’s definitely an important part of the mix.
“If you do the work properly and you design it properly, it will have a positive impact. It won’t stop flooding - that’s an important point to make - but it will reduce the risk of flooding.
“It will also increase the amount of wildlife and the visitor potential. Areas tend to have more investment in them if they are well wooded.
“It will make a very valuable contribution to slowing the flow of water. The evidence suggests that even just after a few years, tree planting positively impacts the soil structure, so it increases the infiltration rates.
“That can happen relatively quickly. In the longer-term, we’re looking at between ten and 20 years to start having a real impact.
“It’s going to be gradual, over time, but I think after three or four years we will notice some local improvements to the catchment.
“To do this work for the Calder Valley and all the other valleys in the Leeds City Region, it does need a catchment-wide approach.
“In many ways, this is about looking at what works. We want to work in collaboration with the University of Leeds and the Environment Agency to trial different techniques to see what works and then roll it out in different places.
“There is quite a lot of data already, but we think for this particular part of the South Pennines, we’ll take this opportunity at Gorpley reservoir to sharpen up what we know, what works, cost benefits and that sort of thing.
“It’s a really good opportunity.
“This site in itself won’t solve the problem, but we’re hoping to use this as a trial and hopefully inspire other landowners and tenant farmers to come forward and maybe we can work with them to target areas for woodland creation.”
He added that volunteers and local groups, including Treesponsibility, would work with them to begin planting trees.
Yorkshire Water said its Gorpley Reservoir is already used for flood attenuation rather than water supply. The Environment Agency alters the releases of water to try and maintain the reservoir at 73 per cent full or below to enable it to act as a sink at times of high rainfall.
Earlier this month Floods Minister Therese Coffer visited Mytholmroyd to see the design options for a £15m flood alleviation scheme.