A smiling man holds his phone up whilst looking at a river

The Big River Watch

Survey your local river between 6th-12th of September and be part of our UK and Ireland-wide survey of river health.

Did you know? There's a free and easy way to help support your local river.

Twice a year we run Big River Watch weeks. where we invite you to take part in a simple citizen science activity that helps build a picture of river health across the UK and Ireland.

The next Big River Watch takes place between 6th-12th September 2024.

Our rivers are far from healthy. They're polluted with sewage, plastic, chemicals and nutrients, and just 15% of river stretches in England are in good overall health. This isn't good enough.

When it comes to restoring our rivers, we need even more information about how they're doing. You can help us identify and locate the issues.

So whether you’re a swimmer or a paddler, an angler or a rambler, a wildlife spotter or a sit-and-watch-er, download the app and complete the quick survey today! However you love your river, Big River Watch is a chance to be part of the movement improving our freshwater spaces. With our app, you can contribute to a national data set that will help us build a picture of river health.

Download the Big River Watch app

You'll need the free app to take part! Download it before you set off to complete your survey.

Taking part is easy:

  • Step 1: Download the app
    Download the free Big River Watch app on your smartphone before visiting your chosen river.
  • Step 2: Take part
    Pick a riverside location, spend 15 minutes observing, and answer the questions in the survey. You can complete the Big River Watch at your favourite local spot, or get to know somewhere new.
  • Step 3: Upload
    Upload your Big River Watch survey. It's that simple to get involved!

Tell us about the things that you see with the survey - from wildlife and plants, to the flow speed of the water and whether you can spot any pollution. If you don't know what you're looking at, use our handy in-app ID guides for pollution and wildlife.

Then our river specialists will analyze the results. We share data too, so that it can be used by other environmental organizations, journalists, and community groups to help in the fight for healthier, wilder rivers.

The app and survey are open year-round, so you can keep recording useful information about your local river at any time, if you wish.

Share your experience and your photos on social media using #BigRiverWatch.

Why is Big River Watch needed?

Rivers are suffering from a deluge of pollution, and all across the UK and Ireland our vital freshwater ecosystems are failing their health tests. To change this, we need to know where our rivers are having the problems and which problems are the most prevalent. The free and open Big River Watch survey is your chance to make a difference. Data gathered during Big River Watch can support policy change; helping turn the tide on plastics or stem the flow of untreated sewage. It also helps identify the best places for river clean-ups and litter picks, or places which would benefit the most from the creation of things like wetlands.

Download our handy Wildlife and Pollution Identification Guide PDFs.

The results

Around 9,000 of you have now taken part in a Big River Watch week. working together to submit over 3,600 surveys. You can explore some of the data from both events in our new Big River Watch Data Dashboard.

Here are some of the photos that you took whilst taking part in the Big River Watch in May 2024

A white adult swan swims next to several baby swans
A small mayfly sits on an outstretched finger in front of a river
Blue skies and green vegetation around a small river
Citizen science equipment in front of a river bank
A dramatic orange sunset is reflected in a wide river


No, you do not need to be an existing volunteer with a local Rivers Trust or NGO. This app and experience are open to everyone - you just have to be able to access a river in the UK or Ireland during one of our Big River Watch weeks.

Yes, while we're interested in getting as many of you involved over our bi-annual Big River Watch weeks to get a clear snapshot of river health at to points repeated in the year, the app and survey will also remain open to collect data year-round. So, if you run a volunteer group or you're interested in continuing to add information about your local river to the dataset, you can use the app at any time.

No. You do not need existing experience or knowledge on river health or river environments. In fact, we'd love for people who don’t know much about rivers yet to participate too.

Absolutely. You do not need to be a tech whizz, but you will need a smartphone that you can install apps on.

Yes. You will need to be able to visit a river in person. It doesn't matter where you live, or whether your local river runs through a city, town or the countryside, as long as you complete the survey whilst looking at it.

A river is generally too wide for anyone to jump across (greater than 1.5m wide).

When rivers thrive, we thrive, but when rivers suffer, so do we. 0% of rivers in England and Northern Ireland are in ‘good’ overall condition. Rivers are suffering from sewage, plastic, chemical and nutrient pollution. To change this, more data is needed. We need to know where our rivers are having the problems, and which problems are the most prevalent. By sparing just 15 minutes, everyone can be part of the solution. Data gathered can support policy change; helping turn the tide on plastics or stem the flow of untreated sewage that reaches our waterways. It also helps identify the best places for river clean-ups, and spots to install things like leaky dams which slow the flow, boost biodiversity and reduce flood risk!

We know some of you may not own a smart phone and so we have created this offline Word version for you to use. Just simply fill it in and send it back to us [email protected].

Please note that you must read and agree to the Health and Safety Guidance before taking part, which can be found here.

Yes. Please take a look at our health and safety pack here.

See our privacy policy for the Big River Watch.

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