Drought Archives - South East Rivers Trust

Mapping out a vision for the River Mole

Posted on 27 June 20233 July 2023 by Ian Lamont

The health of the UK’s rivers is increasingly at the forefront of the public consciousness. It is therefore vital that organisations working to protect and restore our rivers communicate openly and effectively with the public through innovative channels. It is also vital that all organisations working on a river network combine their efforts in a collective approach. What happens upstream affects the downstream.

We are delighted to launch the latest in our series of catchment ArcGIS Storymaps, on behalf of the wider River Mole catchment partnership. This partnership brings together about 45 organisations and individuals who are committed to protecting and enhancing the health of the watercourses across the entire river network. The South East Rivers Trust (SERT) co-hosts the partnership with the Surrey Wildlife Trust.

Through the River Mole Storymap anyone interested in the multiple threats to the river’s health, and the activities of the Catchment Partnership which aim to mitigate those threats, will be able to access detailed information, beautifully mapped for context and understanding.

Below, Dr Lewis Campbell, the Catchment Manager, provides a brief introduction to the Mole catchment, and highlights the work some of the organisations involved in its care and restoration.

Clay and chalk bring different issues

The catchment of the River Mole covers an area of just over 500km², spread across Surrey and West Sussex. The catchment is largely rural pasture and farmland, but is home to some significant urban areas including Crawley, Reigate, Dorking, and Leatherhead.

The catchment’s main watercourse, the River Mole, rises to the west of the town of Crawley, before flowing for 80km until it joins the River Thames opposite Hampton Court Palace.

Differences in the natural characteristics of the catchment in its upper and lower reaches provide a division into two sub-catchments. The area from the town of Leatherhead down to the confluence with the Thames forms the Lower Mole and Rythe sub-catchment, whereas the area above Leatherhead forms the Upper Mole sub-catchment.

Across its watercourse, the River Mole is joined by numerous tributaries, including the Gatwick Stream, Tilgate Brook, and Baldhorns Brook, to name a few. Although the river largely flows over clay, it carves out spectacular cliffs in the chalk bedrock in the area between Leatherhead and Dorking, also known as the Mole gap.

Challenges include pollution, weirs, flood and drought

Tilgate Weir prevents fish passage — A weir at Tilgate is one of many barriers to fish passing along the river

The water bodies that make up the Mole catchment vary in their Water Framework Directive (WFD) classification status from Moderate to Poor, and this reflects the numerous and varied challenges facing the catchment.

The major issue impacting the catchment at large is pollution from waste water sources. The catchment is home to several relatively large towns, so there are a number of sewage treatment facilities present which discharge treated effluent directly into the river, and occasionally also untreated sewage in times of higher than usual rainfall.

The Storymap allows residents to see Thames Water’s live sewage release data. These discharges carry with them excessive nutrients, such as phosphates and nitrates and micro-organisms, which can have a negative impact on the quality of the habitat available for aquatic life such as fish and plants.

The catchment runs primarily over clay. Couple this with the relatively large urban areas and the presence of the UK’s second largest airport (Gatwick) and rain that falls on the catchment very quickly makes its way into the water course, directly from hard surfaces such as roads and runways, or from fields.

This run-off carries with it numerous chemicals and other pollutants which can also degrade the quality of the river habitats available for wildlife. In rural areas, run-off will also carry significant amounts of soil and sediments from fields which can clog up the valuable gravel areas in which aquatic invertebrates like to reside, reducing the food availability for larger organisms such as fish.

Another issue is that fish are also negatively affected by the numerous barriers within the catchment. These barriers are often types of weir – solid structures placed into rivers to alter their level and flow. These physically stop fish from navigating the full extent of the water course. This prevents them from accessing the variety of habitat types that they require to thrive, something particularly harmful to those species such as salmonids and the critically endangered European eel which have complex life cycles that involve migration to and from the ocean.

Parts of the River Mole are prone to low flows

Interestingly, the catchment is prone to both flooding and problematic low flows. Many of the catchment’s waterways have been historically altered to make them more navigable, or to make way for development. This often involves straightening and re-enforcing the river channels, which disconnects the river from their adjacent flood plain.

Disconnection from the flood plain means that during periods of heavy rainfall the water which quickly runs over the catchments clay and concrete into the rivers has no way of escaping the channels, resulting in excessively high water levels and flooding. Conversely, in times of low rainfall, connected flood plains can retain water which slowly makes its way into the watercourses, maintaining flow. A lack of connected floodplains in the catchment means that the Mole and its tributaries often experience low flows during the height of summer, again negatively impacting aquatic life.

Water quality work under way

As the climate becomes more unpredictable it is likely that these issues will occur more frequently or with increased severity. Fortunately, there are steps that we can take to try to avoid this situation, or help the catchment cope.

Partnership members work either individually or together on projects to improve the catchment, but meet on a regular basis to share expertise and experience. The idea is that by working together, groups can pull their knowledge and resources together and agree actions that are right for the whole river (a holistic approach) rather than act in isolation on small sections.

One of the partners, the River Mole River Watch, which is spearheading catchment wide water quality monitoring efforts through their network of volunteers. This initiative will allow the partnership to identify locations which are being particularly impacted by pollution and poor water quality. Armed with this knowledge, catchment partners will then be able to design and implement measures to prevent pollution, or reduce its impact.

Learn more about our eels project and Crawley focus

European eel image Photo by Darryl Clifton-Day

SERT also works with communities and landowners to identify ways to reduce run-off pollution in urban and rural environments, such as changes in land management practices.

Where reduction of pollution is not possible, SERT is involved in projects to improve river habitat, create backwater refuges and remove barriers so that fish and other aquatic organisms can move into less polluted areas. SERT is also leading on projects to reconnect the waterways of the Mole catchment with their flood plains, providing natural flood management and low flow resilience.

Our work at SERT on the Mole already, among many listed on the Storymap, has included a project to promote and help the critically endangered European eel. During the Thames Catchment Community Eels project – part of wider work on several rivers across the south east – we found twice the number of barriers to eel migration, such as weirs, as had been recorded previously. We also ran workshops and assemblies for 1,136 children and put on other public education sessions, to highlight how this species of fish needs to be able to reach the ocean to complete its life cycle.

We are currently working up our Caring for Crawley’s Rivers project, which will combine river restoration with community engagement such as education in schools and with other groups.

With our newly launched catchment Storymap, you can take a deeper dive into River Mole catchment and the actions that our catchment partners are taking to protect it. You can also find information on opportunities for you to get involved.

Visit our River Mole Storymap, find out about the work to protect and enhance the river and how to get involved!

The answer to drought lies in working together to build back wetter

Posted on 22 March 202323 March 2023 by Ian Lamont

On World Water Day, Dr Sam Hughes highlights our Holistic Water for Horticulture project, working with growers to make the most of every drop of water in the face of a changing climate which is likely to bring more droughts.

Last summer’s brutal drought was a stark indication that we are entering a “new normal” of hotter summers, milder wet winters and more frequent extreme weather events, from dry spells to intense rainfall.

Climate change is real. Temperatures reached 40C for the first time in England last year. The south and east of England had the driest July on record. Rivers ran low. Wildlife, people and businesses all suffered.

The message for tackling the climate crisis from the Rivers Trust at the time was clear. We need: a faster, more coordinated government response to extreme weather impacts; investment in water infrastructure to reduce leakage; clear support and guidance on measures to reduce household consumption; and the need to build back wetter.

The National Drought Group’s leader Sir James Bevan, the Chief Executive of the Environment Agency, acknowledged the need for change on a massive scale:

“For the coming year and… for the coming decade, a complete gear change is needed for how water companies and all water users, from farmers to households, think about how they use water and understand its fundamental value.”

A wet winter, comprising five consecutive months of above average rainfall, might have lulled some into a sense of security in the short term. However, the driest February for 30 years has been a rude awakening to 2023, bringing the possibility of another period of drought for a horticulture sector in crisis, in a region of the country already classed as water stressed.

Working for water resilience, food security and environment

Water is the foundation of the horticulture sector and this is keenly felt in the drier, more crowded catchments of the South East, where lots of water is needed for a long time by a lot of farms.

Precision irrigation for crops is required to ensure the best use of precious water resources

High value protected edible crops (soft fruit, tomatoes, peppers and cucumbers to name a few) require precision irrigation over a long growing season. Out in the open, newly planted fruit orchards should be irrigated to allow young trees to establish, thrive and produce crops to support and expand business.

During the 2022 drought, a lot of growers scaled back crop areas, which ultimately affects consumers through limited availability. Many supplemented irrigation with mains water, an expensive commodity that further eroded shrinking profit margins already squeezed by inflation, labour shortages, higher labour costs and inflexible supply contracts.

Is it any surprise that these circumstances have resulted in contraction across all UK food production sectors?

Innocuous terms like “scale back” and “contraction” belie the extreme hardship being felt by businesses across the sector, especially smaller ones. The vulnerability of domestic food security has been laid bare, set against a landscape of highly altered sourcing catchments unable to cope with climate change impacts. Without acting collectively in order to drive change to lessen such impacts, businesses, supply chains, communities and the natural environment will ultimately fail.

The Courtauld 2030 Water Roadmap was launched by WRAP, the Rivers Trust and the World Wildlife Fund to meet “the challenges we face in protecting critical water resources for food supply, for nature, and for local communities” in key sourcing catchments across the UK and abroad.

The Roadmap target is for 50% of the UK’s fresh food to be sourced from areas with sustainable water management by 2030.

The South East Rivers Trust (SERT) is keenly aware of the pressures the region’s horticulture sector faces to balance water resilience, food security and environmental needs while staying in business, through our work with the Holistic Water for Horticulture project (HWH), a Courtauld 2030 Water Roadmap project. This promotes a collective approach to water and land stewardship.

The answer to being able to respond to the impact of dry spells lies in how we capture, retain and use water from our wet periods.

The pathway to water resilience is clear:

we need to build back better and wetter
it is better to work together and proactively to reap bigger water resilience benefits

Helping landowners avoid drought

HWH uses remote data to map and identify areas of present and future water risk in the South East. This high level approach is vital for targeting engagement in high risk areas, to raise awareness of the challenges that growers and neighbouring landowners might face if droughts became a “business as usual” scenario.

HWH staff make site visits to discuss water challenges and potential site-tailored solutions that can, in some cases, bring multiple benefits.

Winter and high flows from rivers and rainfall from rooftops and polytunnels should be captured and stored for irrigation. Currently, rainwater from buildings and polytunnels can be harvested without a water abstraction licence, reducing dependence on expensive mains and diversifying water resources that support business resilience and growth.

Still a relatively new concept, water trading and sharing between water abstractors across a given area will result in a more dynamic water management landscape.

Nature-based solutions such as wetlands, scrapes, planting native flowers, shrubs and trees in areas that are prone to flooding can provide alternative sources of income (carbon credits, biodiversity net gain, stewardship schemes) to growers alongside cropping areas.

Wetlands and scrapes provide advantages to land owners

These measures benefit both nature and neighbours by slowing the flow from extreme rainfall events, mitigating flood and reducing soil erosion and damage to property.

Elsewhere across SERT’s work, we work to retain water in the landscape through projects such as PROWATER, one of 10 pilots supported by the Interreg 2 Seas European Regional Development Fund.

Working together instead of in isolation to address the many challenges that face the sector packs more of a punch. Farm clusters, producer organisations, cooperatives and abstractor groups can be powerful lobbies that share information and drive change across the sector.

These are the motors of change – for water resource management and large-scale delivery of measures, such as Landscape Recovery projects through Environmental Land Management Schemes (ELMS), that benefit growers.

By joining forces with environmental experts at SERT through projects like HWH and PROWATER, these powerful groups can identify, develop and deliver solutions and make connections with different water users and stakeholders across the catchment prepared to invest in measures and innovation that benefit them too.

Are you a farmer or grower who would like advice on water resilience and management issues? Fill in our request form to book a visit from our experts.

The bigger water saving picture

Posted on 15 August 202216 August 2022 by Ian Lamont

The recent and prolonged dry spell has brought water scarcity in the UK into sharp focus. Several water companies in the south of England have triggered restrictions, including hosepipe bans.

On 12th August the Environment Agency declared drought in eight out of 14 water areas. Unfortunately, this is likely to be the future. We can’t just pray for rain. We need to regenerate river catchments and plan for the climate crisis.

Robyn Shaw, Assistant Education and Engagement Officer at the South East Rivers Trust, looks at the factors around water scarcity and introduces our Water Saving Tips page, which emphasises that the issue is one we must all take responsibility for and think about all year round.