Preventing Plastic Pollution

Plastic pollution is a serious threat to our natural environment, with an estimated eight million tonnes of plastic waste escaping into the oceans from our rivers and coastal nations every year.

As part of the international Preventing Plastic Pollution (PPP) project, the South East Rivers Trust focused on the River Medway over the course of three year period, between 2020 and 2023. We worked with communities, schools, businesses and other partner organisations to understand, remove and reduce plastic pollution.

The overall PPP project brought together 18 organisations from across France and England. It was funded by the EU INTERREG VA France (Channel) England Programme project, and co-financed by the European Regional Development Fund to target seven pilot sites: Brest Harbour, Bay of Douarnenez, Bay of Veys, Poole Harbour, and the Medway, Tamar, and Great Ouse estuaries. In addition, SERT gained Heritage Lottery Fund support.


  • Three-year project finished in


  • Partners across the UK and France


  • Pilot catchments


  • Group cleanups with volunteers


  • River Guardians recruited


  • Workshops, pop-up stalls and school sessions


The aim of the project

The PPP project sought to understand and reduce the impacts of plastic pollution in the river environment. By looking at the catchment from source to sea, the project aimed to identify and target hotspots for plastic pollution, embed behavioural change in local communities and businesses, and implement effective solutions and alternatives to single-use plastics.

Additionally, this international project aimed to improve the quality of Transitional Waters across the France (Channel) England area  by:

  • Developing a scalable and transferable mapping tool to provide quantifiable evidence of sources and quantities of plastic pollution in catchments.
  • Developing a portfolio of trialled and tested innovative interventions to reduce plastic waste in or entering catchments.
  • Enabling behavioural change within target groups and demonstrating best practice.
Plastic pollution. 80% of marine waste comes from rivers - and 50% is single use

The problem with plastic

Plastic is one of the most versatile materials ever invented and is cheap to produce. This is why it is largely used by a wide range of industries for a huge variety of uses.

However, when it is not disposed of appropriately it becomes a problem: plastic never totally degrades, it only breaks down into ever smaller pieces that become invisible to the naked eye. Microplastics, as they are known, not only become virtually impossible to remove from the environment, but can also enter the food chain.

The impact it can have on the environment is huge, not only at the point of production but in particular at the end of its life.

For these reasons the Preventing Plastic Pollution partners worked together to assess the status of the target areas, to identify sources and pathways of plastic pollution and remove it from the environment.

They then used the evidence gathered to engage with communities, businesses and other stakeholders, locally and nationally, to encourage behaviour change away from single-use plastic.

Volunteers tackling plastic pollution © South East Rivers Trust

Mapping out the Medway's plastic problem

Despite the highly publicised problem of plastics in oceans, previous schemes to address the problem have failed to look upstream and systematically tackle the role that rivers play as a pathway and source of plastic.

The South East Rivers Trust worked with the Living River Foundation and Queen Mary University London (QMUL) to collect and analyse samples of water in the Medway and to understand the presence and composition of microplastics in the catchment.

The results showed that the Medway catchment is relatively uncontaminated with microplastics – less than five millimetres in diameter (mean concentration: 0.9 particulars per cubic metre).

The highest microplastics concentrations were downstream of major towns (Maidstone/Rochester). The most frequently detected microplastics in freshwaters were polypropylene (PP), polyester and other polymers, while in the tidal river and estuary PP, polystyrene and polyethylene (PE) were dominant. Smaller microplastics particles tended to be polypropylene, while larger microplastics were most often identified as polyester, PE or other polymers.

We also looked at macro-plastics (bigger than five millimetres in diameter). This was to understand the most common causes of plastic pollution in the catchment and their sources. In order to identify these, our GIS analyst team created a plastic pollution hotspot map of the Medway.

Risk factors, such as proximity to landfill sites and densely populated urban areas were identified and sourced across the whole Medway Catchment Partnership. This was so that all maps were based on the same risk allocation system and can be compared.

The plastic hotspots map of high risk areas for plastic bigger than 0.9mm

Removing plastic pollution

During our PPP project we ran numerous activities to assess which ways are most effective and sustainable in the long term at removing plastic pollution from the environment.

These included:

  1. One off litter-picking events/cleanups.
  2. River Guardian and Plastic Champion programmes to allow volunteers to tackle plastic pollution in their own time and to look after their local stretch of the river.
  3. Sessions for community groups to help them understand the problem of single-use plastics and encourage them to reduce their reliance on such items.
  4. Experimenting with litter trapping devices, known as drain guards.
  5. Discussions about end-of-life solutions for plastics: we organised a webinar for growers and landowners in the Medway to learn about available services to recycle non-packaging plastics used in agriculture.
Clearing litter in Tonbridge

Community litter picks

Working with local volunteers, SERT targeted hotspots to remove plastic pollution from the Medway and categorised much of the litter. We built strong relationships with several groups, including the Medway Swale Estuary Partnership, Medway Valley Countryside Partnership and Friends of the River Medway.

In less than two years and with the help of local community groups and organisations, 583 volunteers joined SERT’s PPP team on 27 cleanups.

Thanks to their priceless help, we removed more than 1.5 tonnes of rubbish from various locations. Venues ranged from Forest Row in Sussex, near where the Medway rises in Ashdown Forest, to towns such as Maidstone, Tonbridge and Rochester all the way to the Kent coast.

Volunteers met us on riverbanks and foreshores and some partners even helped us collect rubbish from places inaccessible by foot, using canoes and paddle boards.

Among common plastic items collected and sorted were:

  • 2,893 unidentifiable pieces of plastic
  • 1,600 crisp packets and wrappers
  • 824 drinks cans
  • 668 plastic drinks bottles
  • 757 bottle caps and lids
  • 357 cotton bud sticks
  • 289 plastic bags
  • 174 plastic straws
  • 173 pieces of cutlery, trays and food pouches
  • 254 takeaway containers
  • 767 cigarette butts, which contain plastic
  • 215 wet wipes
Engaging schools about plastic © South East Rivers Trust

River Guardians and Plastic Champions

Alongside the effort of event volunteers, 70 local residents enrolled in our River Guardians programme for the Medway catchment. We provided them with training and the equipment to look after their preferred stretch of the river in their own time.

Of these 583 volunteers, 43 became Plastic Champions, individually reporting the types of plastic they found, to support the litter data collection efforts. These plastic champions were provided with additional training and equipment on how to collect and upload data.

Visit the parent PPP website to see the overall impact of volunteers across the channel.

The information we have been gathering through cleanups and the programme is key to addressing the issue of plastic pollution at its source, plus supporting campaigns against single-use plastics with solid data.

This type of data collection informed campaigns that led to the ban of single-use items and phasing out of plastics from wet wipes.

Residents were encouraged to sign up as River Guardians

Investigating pollution with drain guards

As part of the PPP project’s efforts to investigate different methods of stopping plastic reaching our waterways, SERT installed six drain guards in streets around Maidstone city centre. We did this in partnership with Kent County Council, Ultratech Ltd and Fosse Liquitrol.

Monitoring them every six to eight weeks over a period of nine months, these drain guards – nicknamed witches’ hats – helped us assess which types of plastic pollution were being washed down drains into rivers from urban streets.

Plastic items were found in every drain guard at every monitoring session. Over the course of the trial, the drain guards removed more than 774 items.

As detailed in our blog about the trial, cigarette butts (423) were by far the most common type of rubbish found. These contain a synthetic plastic fibre – cellulose acetate, which takes years to break down.

While the next highest type was “unidentifiable plastic items” (172), other common finds were bottle tops, food wrappers, receipts, sweet wrappers and chewing gum. The plastic item type varied between location, with litter affected by footfall frequency, proximity to shops, pubs or roads.

The trial showed the potential to scale up and prevent plastic entering surface water drains – and rivers.

There is potential to scale up the use of drain guards to capture, remove and analyse litter to stop it ending up in rivers

Working with businesses, schools and communities

We held sessions with several different groups, schools and local businesses. The emphasis was on how to reduce single-use plastic and the resultant pollution of the River Medway.

These included:

  • 14 sessions with secondary school pupils, broadening SERT’s educational reach. Devised for Key Stage 3 and 4 pupils, these workshops challenged and empowered students to come up with creative solutions to address plastic pollution in their school and local area.
  • 11 Pop up stalls at community events and markets to engage with local residents and other stall holders. Displaying plastic-free household products to start conversation and discuss incentives, pros and cons of single-use products and their alternatives. Bee-wax wraps making activity to start conversation and for participants to take home and trial.
  • 7 Community workshops, for groups and small businesses which wanted to actively reduce their reliance on single-use plastic. We launched these events online and invited people to participate. We discussed most commonly found single-use plastic litter, their potential origin and solutions to tackle them. We then developed ’plastic action plans’ to include actions/step-by-step paths for participants to follow up in the short term, including developing campaigns and contacting the relevant local authority.
Workshops helped groups devise plans to tackle plastic together

Would you like to continue tackling plastic in the Medway?

Although our funded PPP work has ended, you can still protect the Medway, either on your own or by linking up with others to collect litter.

We have created a map that shows you plastic pollution hotspots right across this vast network of waterways. The darker the shade of brown the higher the risk of plastic pollution. This shows you where litter picking is needed.

You’ll also find the relevant local authority to contact to arrange collection of waste. Some of them lend or provide equipment for free. You can opt to join one of the many events organised by organisations working locally to you.

If you would like to show the impact of your work or if you wish to inform us of other issues that might be relevant to us, please use this form.

You could continue picking litter on the Medway, even though our Preventing Plastic Pollution project has ended

The Preventing Plastic Pollution partnership

  • Queen Mary University of London
  • LABOCEA Conseil, Expertise et Analyses
  • Syndicat mixte établissement public de gestion et d’aménagement de la baie de Douarnenez
  • Office Français De La Biodiversité, Parc naturel marin d’Iroise
  • Brest Métropole
  • Centre national de la recherche scientifique
  • Counseil départemental de la Manche
  • Institut français de recherche pour l’exploitation de la mer
  • Environment Agency
  • The Rivers Trust
  • Syndicat de bassin de l’Elorn
  • Brest’aim
  • Westcountry Rivers Trust
  • South East Rivers Trust
  • Plymouth City Council
  • Department for Environment, Food and Rural Affairs
  • University of Plymouth
Hadlow College sorting plastic © South East Rivers Trust

Thanks to our supporters

Preventing Plastic Pollution
Heritage Lottery Fund
Medway Swale Estuary Partnership
Medway Valley Countryside Partnership