As part of the Loddon Observatory programme, we are working in partnership with a number of organisations and local landowners and residents to establish a long-term research platform in the Upper Whitewater valley. Our aim is to investigate a range of issues related to the management of water resources and water-dependent ecosystems.
The Whitewater is a tributary of the Blackwater, which itself flows into the Loddon near Swallowfield. It rises at springs near Bidden Grange Farm between Upton Grey and Greywell in Hampshire. For its first mile and a half, it flows on Seaford and Newhaven Chalk formations and is largely fed by groundwater seeping from the chalk aquifer, before reaching clay formations near Odiham Castle. Water management in this area is complex due a rich natural and historical heritage, a complex hydrology, and numerous anthropogenic pressures.
At Greywell Fen, an alkaline fen designated as a Site of Special Scientific Interest, we are working with South East Water and Hampshire and Isle of Wight Wildlife Trust to investigate the impacts of groundwater abstraction and land management on the hydrology, geochemistry and biodiversity of this type of habitat. South East Water have installed a large number of sensors to record river flow, precipitation and groundwater levels in the chalk and in the fen. We are building on this sensor network and database, and we hope to generate evidence that will help South East Water and Hampshire and Isle of Wight Wildlife Trust to improve the conservation status of the fen.
Two PhD students, co-funded by South East Water, started working on Greywell Fen in October 2019. Elaine Halliday, supervised by Prof. Jo Clark and Prof. Anne Verhoef, is investigating the hydrology and hydrogeology of the fen. Elaine is also helped by Dr David MacDonald of the British Geological Survey, who will provide expert hydrogeological advice. Phillip Agredazywczuk, supervised by Dr Steve Robinson, is investigating the impact of high nitrate concentrations in groundwater on the biogeochemistry of the fen. Both students are working closely with each other and other members of the Loddon Observatory.
Greywell Fen offers great opportunities for teaching. In 2018-2019, as part of Loddon Catchment Consultancy module, a group of graduate students in geography and environmental science investigated changes in the vegetation of the site over time, using data collected by professional ecologists commissioned by South East Water. Another group analysed hydrological time-series to try to better understand the hydrological functioning of the fen. Finally, Abi Ravichanthiran, a MSc student in Environmental Management, investigated nitrate and phosphate concentrations in the fen to understand its role as a sink for nutrients.
Further downstream, in and around North Warborough Greens and Mill Corner, the Loddon Observatory team is working with Hart District Council, Hampshire and Isle of Wight Wildlife Trust and local landowners and residents to monitor the effect of Natural Flood Management. This supported by the NERC LANDWISE project and PhD student, Gabby Powell. Hampshire District Council is proposing a range of small-scale works that, in combination, are expected to contribute to a reduction in flood risk in Mill Corner while respecting the rich natural and historical heritage of the area. These will include small leaky dams made of logs and branches installed in ditches and small streams, and scrapes and ponds to store more water in the floodplain.
We have installed a large number of sensors that will continuously record water levels and flows in the area. Local landowners and residents have helped with the installation and on-going monitoring.
Our hopes are that the research dynamic that the University of Reading and its partners have created in the Upper Whitewater as part of the Loddon Observatory programme will grow from here. We are preparing other funding applications to work on issues such as paleo-environments at Greywell Fen and digital tools for community flood management.