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The importance of beach cleaning data

4 minute read

Our beach cleans are a little bit different - we not only clean, but survey the litter found at the beach too. The data you collect from these cleans makes real positive changes to our beaches and seas.

Beachwatch Team

Gathering evidence for positive change

We've been running our national beach cleaning and litter survey work for almost 30 years. This means we now have decades of data at our fingertips.

Every year, thousands of people from across the UK either join a beach clean or run their own. These can be private events for their friends and family, or they may be open to the public so more people can get involved.

This data collected from beach cleans is hugely important as it helps us track the common items we find on our beaches and then campaign for change to reduce this pollution.

We use the findings as evidence to lobby Governments for legislative change, as well as to influence industry practices and to drive campaigns.

From plastic bag charges to banning microplastics in personal care products, your beach clean data has helped to make some of the biggest and most significant impacts on beach litter ever.



drop in plastic bags found on UK beaches since 5p charge was introduced

How do we record the litter items?

Our litter survey form lists all the main litter items you're likely to find over a 100-metre stretch on your clean.  It categorises each item according to what it’s made from, with ‘plastics’ being the biggest section.

We ask you to record the data over 100 metres if you can, so we can make the data comparable. 95% of all litter items are likely to be found within a 100-metre stretch, but you can clean as much of the beach as you like!

When doing a beach clean, you'll mark out a 100 metre stretch within your beach clean area. The survey will be completed within this stretch.

It goes along the strandline (the high tide mark – generally seen by a collection of seaweed left on the shore) and you should record all items found, no matter how big or small, along the 100 metres - including width wise from the strandline to the back of the beach.

What happens to the data?

Our beach clean organisers upload their data to our website. If you’re an organiser, you’ll be prompted to do this and shown where to do so when you log on.

This data is then automatically uploaded to our national database where we've been recording beach litter data since 1994.  Our long-term data set is unique in helping to identify trends and patterns over time so we can stop the pollution at source.

The way we analyse our data has changed

We’ve been reviewing how we analyse our data to ensure that it's as up to date as possible, so we can get the very best evidence from it as we continue our work to reduce litter on UK beaches.

We want to do the litter data collected by our amazing volunteers justice, by analysing and sharing it with the widest audience possible. We’re going to be using this information in new ways and looking at things like the seasonality of certain items washing up or being dropped.

Why we’re updating the way we analyse our data

This September, it’ll be 30 years since the Great British Beach Clean started, giving us one of the largest, longest-running beach litter datasets in the world - a UK beach litter snapshot from just one weekend. Beachwatch, is a year-round effort to collect beach litter data.

The Beachwatch dataset is completely unique and hugely important to our work, so we need to ensure the analysis is robust and aligned with current guidelines, such as OSPAR's Coordinated Environmental Monitoring Programme (CEMP) guidelines. OSPAR is the organisation responsible for protecting the marine environment of the Northeast Atlantic.

The survey sheets and litter descriptions we use are already within OSPAR guidelines, but OSPAR recently changed its assessment method for analysing beach litter data. By adopting these changes, we can also ensure that the data we collect, and use, is of the highest quality and accuracy. That way, we can help make the biggest impact.

What will be changing?

There’ll be a few behind-the-scenes changes to how we analyse the data, but the most significant one for volunteers is that we'll no longer include plastic pieces smaller than 2.5cm in our main analysis.

These small plastic pieces (called 'mesoplastics') are the most common type of litter found on UK beaches. They're the bits from bigger items which have broken down over time, so we want to look at them separately.

Because the pieces are so small, we don't know what they were originally or where they came from, so they're classed as 'non-sourced'. This makes it more difficult when looking at where litter comes from.

By separating these plastics out, we can get a truer percentage for sources of litter such as public, fishing, sewage related debris, shipping etc. We still want these items collected but they’ll now be analysed separately, in line with OSPAR guidelines.

The changes we’re making will give us a much more accurate way to look at litter amount averages, that will ultimately give us a clearer picture of current UK beach litter levels.

How will long-term trends be compared if the analysis is changing?

Because of the updated analysis processes, the new State of Beaches report and future figures will not be directly comparable with previous year-round and Great British Beach Clean data. But, we'll be able to communicate the importance of litter prevention more effectively to the public and policymakers.

Although there are some differences in year-to-year fluctuations between the current and new analysis, the overall trend of litter decline since 2016 remains unchanged.

What will our supporters notice?

Rather than only reporting Great British Beach Clean data in November, we'll be sharing our year-round beach litter analysis once a year.

Even though we've always made use of our year-round data behind-the-scenes, every Beachwatch beach clean will now contribute to the public-facing figures we produce – giving us and you even more evidence of the pollution on our beaches to take to policymakers and industry.