A catchment is the basin of land that feeds water into a river system. Essentially, this is the land that rainwater falls upon, with this water generally feeding into a reservoir, river or to the sea. The water Yorkshire Water collects from our catchments as part of their catchment management work is termed ‘raw’ water because this water has not been treated.
The quality of the raw water we collect has been deteriorating in many of our catchments over the past two decades. This is a consequence of pollution, unsustainable land management practices and climate change. Whilst we invest in enhanced water treatment works capabilities to ensure our customers always receive the highest quality drinking water, we know that the issues need to be addressed at the source.
Our catchment management programme includes managing our 25,000 hectares of natural habitats to protect Yorkshire's raw water and biodiversity. In our region, many of the key catchments contain upland peat which must be in a good natural state to provide clean water to our reservoirs, rivers and water treatment works. In an area with high biodiversity and good land management practices, the diverse and complex community of plants, animals and micro-organisms work efficiently to filter and remove contaminants. Our programme also includes tackling a range of water quality issues, such as colour, pesticides, nitrates and saline intrusion.
Whilst peat has been forming in our uplands for many thousands of years, a variety of pressures have resulted in a great loss of peatlands, and a deterioration in the biodiversity of these habitats. Pressures include acid rain from industrial emissions, digging of drainage channels to provide water to grazing lands, increased grazing, wildfires and inappropriate burning for grouse moor management. As peatlands are a major storage of carbon in the world, damage to peat causes it to release its stored carbon in to the atmosphere; contributing greatly to greenhouse gas emissions and therefore impacting the environment. Damage to peatland also contributes to colour and sediment in the raw water we collect, making the drinking water we supply to our customers more difficult and expensive to treat. It is in our interest and the interest of the wider environment to return our peatland back to their original state.
Over the last 10 years, we have invested in extensive monitoring, research and innovative land maintenance and restoration techniques. Through multi-agency partnerships such as the Yorkshire Peat Partnership, we have delivered a range of industry-leading activities.
We have worked with others to restore up to 3,250 hectares of degraded peat. We have installed bunds to block up gullies and grips which allow water to be stored, areas have been seeded with nurse crops, such as grasses which stabilise the surface, then covered with heather brash (cuttings from the management of old patches of heather). This allows the return of good peatland plant species, such as sphagnum mosses and cotton grass. The habitat begins to regenerate and develop, allowing other rarer species such as insects and upland birds to colonise - widening the biodiversity.
In December 2013, we published our operational and investment plans for the period from 2015 to 2020. Our plans were developed using a multi-agency approach and responded to our recent investigations and modelling into the reasons for raw water quality failures associated with catchment management.
In 2013, together with the Environment Agency, Natural England and the National Farmers Union (NFU), we started to establish a partnership approach to the development and implementation of Safeguard Zones and supporting Safeguard Zone Action Plans. These zones and plans are being established to better protect the catchment areas that influence the quality of water collected for drinking water.
In early 2014, our catchment manager joined Defra’s Best Practice Burning Group to help them develop sustainable land management guidance and policy that will better protect and enhance UK uplands. We are working with a range of relevant organisations, including the Moorland Association, Natural England and the NFU.
Our future moorland management programme will deliver investigation and implementation activities in the catchments where colour pollution is likely to overwhelm water treatment works capacity in the longer term. We will also be investigating nitrate and other pollutants that present risks to a number of our groundwater sources.
Yorkshire Water owns and manages around 120 reservoirs. Many of these were built in the 1800s and present significant maintenance and repair challenges. Very rarely, they become uneconomical to maintain to modern standards so they are decommissioned. Decommissioning usually involves reducing the volume of water to avoid any flood risk should the structure fail. This can present an opportunity to create good habitats for Yorkshire's wildlife.
The decommissioning of the Beaver Dyke reservoir near Harrogate was five years in the planning. We assessed its value to aquatic life and safety issues against various options up to and including restoring the valley back to its original upland stream roots. Our research showed that the best option is to reduce the volume of water below that, which would pose a flood risk whist maintaining some lake habitat to support its aquatic residents.
In the winter of 2013/14, we began the work of reducing the volume of water by cutting a notch in the dam wall and re-landscaping the old features to create a small lake and meandering stream.
The consequence of decommissioning is improved biodiversity through the creation of a mosaic of habitats that include basking sites for reptiles and invertebrates, low nutrient grassland and moor land pockets and the lake and stream for aquatic species. We expect that the re-colonisation by native plants and animals will take a few years to mature and cover all the old structures remaining on site.
Over the last five years, Yorkshire Water’s warden at Tophill Low has been working with his team of volunteers, the Environment Agency, Natural England, Yorkshire Wildlife Trust, the Internal Drainage Board and the East Riding of York Council to reintroduce the rare and threatened wetland plant The Greater Water Parsnip (Sium latifolium). This plant was all but extinct from the Holdness area until botanist Bryan Mallison discovered plants at Hornsea Mere. A breeding and reintroduction program has been on-going, with the largest population of this plant in the Wolds now existing at Tophill Low.
Over the last four years, we have been undertaking a ground-breaking ancient woodland restoration project across 75 hectares of our land.
Native woodlands have great biodiversity, as they support thousands of species including plants, insects, fungi, birds and mammals. Ancient woodlands are those that have stood since 1600 or before, so they contain a stable thriving community that has developed over more than 400 years. In recent history, many of these sites have been felled and replanted with fast growing forestry crops such as pines and larches, leading to a loss of species and biodiversity.
Our ancient woodland restoration project is removing non-native species of shrubs and trees and replacing them with our native species. This restores the woodland close to its original and natural state, and allows the soil to recover. As the ecosystem is more stable it holds more carbon, filters water more effectively and prevents erosion - all great benefits to the environment and Yorkshire Water.
We own and manage a significant amount of land around our Harlow Hill treatment works which we keep neat and tidy to allow us to inspect equipment for leaks and contamination. Recently however, following talks with Pinewoods Conservation Group, the Harrogate District Biodiversity Action Group and the office of Andrew Jones MP, our Product and Process Manager at the site, Darren Lynch, has changed the management of a patch of this land. By reducing the mowing regime, we will allow shelter and food for wildlife to increase in diversity by up to 500%. Pinewoods Conservation Group and Harrogate District Biodiversity Group will be working in partnership with us to monitor the site and to talk to local residents about the value of leaving areas to grow wild.
Invasive species present increasing challenges to the land and water we manage, as well as to our assets and operations. We have drafted a policy on our approach to invasive species and are currently formalising this internally. We have shared the draft policy with our independent Environmental Advisory Panel and received their support for our approach. When we have finalised our policy, we will share it with our stakeholders. We have included actions in our investment plan for 2015 to 2020 to manage invasive species. For example, we will work in partnership with others on projects to address invasive species in and on the banks of our rivers as part of wider river catchment management plans. This will involve landowners working together collaboratively on stretches of river to maximise the success of controlling problem species.