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12 days of Rivers Trusts – Day 4: Introducing South East Rivers Trust

12 days of Rivers Trusts – Day 4: Introducing South East Rivers Trust

When did your Trust form? 

The South East Rivers Trust (SERT) is a grassroots environmental charity with a vision to achieve healthy river ecosystems, for all, across the south east of England. Our mission is to deliver outstanding river ecosystem enhancement through science-based action, collaboration and engagement.

We started out as the Wandle Trust, a volunteer-led charity working on just one river in South London registered in 2000. In 2009, we recruited our first member of staff and as our experience, expertise and impact grew, we were asked by communities and local organisations to expand our area of operation. In 2013, we covered three rivers and changed our name to the South East Rivers Trust. Today, we cover an area between Reading and Dover, working across 12 river catchments.

How many people work at your Trust?

We are currently lucky enough to have 14 members of staff working at the Trust.

What are the main issues with rivers in your catchment?

The Trust works across 12 different river catchments in the south east of England. Across this area, we have very urban rivers in south London with concrete banks and culverts, to large, rural rivers facing the impacts of previous agricultural practices.  While each river is unique, the main issues negatively impacting our rivers across the board can be summarised by poor water quality, a lack of habitat and poor water management – whether there is too little due to abstraction, or localised flooding.

Are there any particular rivers keeping you up at night and why?

The river keeping us up at night is the Hogsmill River – one of the only 200 remaining chalk streams in the world. Sadly, this river has been long-suffering from regular pollution inputs of raw sewage.

One source of sewage can be found in the river’s headwaters where there are two sets of storm tanks. The tanks function as temporary storage for untreated sewage as it travels through the network of pipes towards the Hogsmill Sewage Treatment Works (STW). During heavy rainfall, rainwater, as well as sewage, fills up the system: to prevent it backing up into homes, there are temporary storage systems like these storm tanks, and sometimes overflow pipes into rivers (known as combined sewer overflows), which help to relieve the pressure.  Usually, the storm tanks contain the sewage until the rain has passed and the sewage can drain back into the network to be treated at the Hogsmill STW. However, occasionally, during higher rainfall, the storm tanks fill up completely and will discharge any excess sewage to the Hogsmill river itself.

This system was designed when the population of London was much lower and the area of paved urban surfaces (which cause rain to run off rather than infiltrating into the ground) was much less. It is a consented discharge – which means it is legal – as it was originally designed to happen only very occasionally as a kind of safety valve for the system (once or twice a year we think), but with population growth, urbanisation and climate change, it now happens more frequently. Our volunteers have monitored around 12 or 14 flow events per year in recent years.

Chalk streams give rise to a unique set of species that depend heavily on the clean, chalk-purified water and are consequently very sensitive to any decline in water quality.  The Hogsmill Storm Tanks are therefore a real threat to the chalk stream species community, even more so because they discharge sewage into the headwaters, affecting the entire river downstream.

These inputs of pollution are particularly alarming as the Trust has witnessed a decline in the volume of water flowing in the Hogsmill in the last couple of years, which means there is less clean water to dilute such pollution events.

Why is this your favourite photo of the year? 

Given all the work the Trust has delivered over the last year, it is hard to pick just one project to showcase as our favourite photo of the year. Instead, we have opted for our new team photo, showing just how much the Trust has grown over the last two years. With new staff members and new expertise, we can’t wait to start delivery in 2019!

What key issue or project will you be hoping to tackle in 2019?

Despite its reputation, England is not as rainy as everyone thinks. For instance, London actually receives less rainfall each year than cities like Miami, Dallas and even Sydney. This means that the South East of England is classified by the Environment Agency as “seriously water stressed” and with projected population increases over the next 80 years, all water companies are looking to find more water to meet the increasing demand.

Within our region alone, there are five water companies supplying water; all of which is abstracted from the natural environment. The more water we use, the more water these companies need to abstract in order to meet the demand, and the less there is in our rivers and streams for wildlife. With climate change altering weather patterns, the implications of this could be long periods of drought, and shorter but more intense heavy rainfall events. Therefore, water scarcity in our rivers is a key issue.

One project we have started delivery on this year to look at water scarcity is PROWATER. PROWATER is a new European project aiming to adapt the south east of England to climate change. Working with partners in the UK, Flanders and the Netherlands, the project aims to increase resilience to drought by improving how water is managed at a catchment scale.

The cross-border project PROWATER stands for ‘PROtecting and restoring raw WATER sources through actions at the landscape scale’. It will contribute to climate adaptation by restoring the whole landscape’s ability to store water through careful catchment management.

Any Christmas wishes or New Year’s resolutions for the Trust this year?

For 2019, the Trust is looking to improve its external communications with a brand new website. The new website will showcase all of the work we do across the south east of England, as well as help local communities find out more about their local river. So watch this space!

Visit the South East Rivers Trust website for more information

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