Improving the Health of our Chalk Rivers

River Mimram surface and under water (c) Peter Tatton

In the approach to World Rivers Day, Herts and Middlesex Wildlife Trust is championing the importance of restoring the health of the area’s rare chalk river habitats.

World Rivers Day is an annual event held on the fourth Sunday in September – this year falling on 22 September. A celebration of the world’s waterways, the day highlights the many values of our rivers, strives to increase public awareness, and encourages the improved stewardship of all our rivers.

In the run up to World Rivers Day, Herts and Middlesex Wildlife Trust, the leading voice for conservation in the area, is drawing attention to the area’s rare chalk rivers and introducing its new collaborative approach to improving their ecological health.

There are only 260 chalk streams in the world, and Hertfordshire and Middlesex is home to 10% of this global resource. These unique river systems are so rare, and support some of our most endangered species – they are England’s equivalent to tropical rainforests. Protecting these unique habitats, and the species that depend on them, such as wild Brown Trout, Kingfishers and Water Voles is more vital than ever.

The State of Nature 2023 report found that nearly one in six of the more than ten thousand species assessed are at risk of being lost from Great Britain. Coupled with that, our chalk rivers are facing a host of challenges posed by pollution, abstraction and modification impacting the flow, quality and physical habitat (the trinity of ecological health for a pristine chalk river). These are compounded by the South East having the highest water consumption rate in the country, being one of the UK’s driest regions, and an increasing population putting consistent pressure on chalk rivers. As a result, less than a quarter of England’s chalk rivers are in good condition and none of those are in Hertfordshire and Middlesex.

Thanks to funding from the Environment Agency, the Trust is working in collaboration with and supporting landholders, communities, and stakeholders, to improve the flow, resilience and ecological health of the River Mimram, which begins near Whitwell and joins the River Lea near Hertford. The Trust’s newly-appointed Chalk Stream and Farm Advisory Officer, Heidi Mansell will be leading this work and the delivery of the Catchment Based Approach Chalk Stream Strategy, calling for chalk streams in England to be given enhanced environmental status and protection.

Heidi says, ‘We’re looking at a new approach with the Mimram – one that’s catchment-wide, considering the entire area of land that drains into the river. That’s really important because specific local issues, for example, the demand for water, pollution or invasive species, may start in the wider catchment area and those that affect or who are affected by them should be empowered to find solutions to those issues. We recognise that for a number of years, different groups and stakeholders – farmers, local communities, businesses, environmental groups, local authorities, and government agencies – have been coming together to improve the Mimram, so now the aim is to consolidate on this good work and make further progress.

‘I’ll be supporting landholders to achieve improvements to the river’s health with the creation and delivery of restoration and management plans, as well as ongoing monitoring to assess our collective progress for nature’s recovery. As a result, we hope to see species such as the endangered Water Vole thrive once again, to see flashes of blue as Kingfishers dart along the river, and to see the long strands of Water Crowfoot teetering on the water’s surface – all indicators of healthy chalk streams. Across the wider catchment, we are aiming to increase the numbers of declining bird species such as Yellowhammers, Lapwings and Corn Buntings – all priorities in the emerging Hertfordshire Nature Recovery Strategy.’

Chloë Edwards, Director of Nature Recovery at Herts and Middlesex Wildlife Trust says, ‘This year, we are marking the Trust’s 60th Anniversary at a point where we are half-way through the most pivotal decade of our lives in the nature and climate crisis. We are steadfast in our commitment to striving to protect our most precious wild places and the wildlife that relies upon them. The new Chalk Stream and Farm Advisory Project is testament to that and takes us a step further to achieving our ambition to see at least 30% of land across Hertfordshire and Middlesex connected and protected for nature’s recovery by 2030.’

The Trust has been working since 2012 on its Living Rivers Project, raising awareness of the issues chalk rivers face and delivering improvements through river restoration projects, working with local communities and catchment groups. Earlier this year, the charity was awarded £1.7 million from the Government’s Species Survival Fund, delivered by the National Lottery Fund on behalf of Defra, to restore chalk rivers in the region and to help halt the decline of over 109 different species associated with the habitat.

To find out more about the Trust’s Living Rivers Project to support chalk rivers in the area and opportunities to support local catchments, visit hertswildlifetrust.org.uk/living-rivers.

Photo credit: River Mimram © Peter Tatton