Information at your fingertips: Our new storm overflow map

09 May 2024


As part of our Get River Positive commitment, we’ve pledged to be as transparent as possible with the data we collect about our water recycling network and the improvements that we're making, especially around storm overflows. Anglian Water’s Head of Spills Strategy, Gail Pickles, showcases the company’s latest online tool designed to help share the latest information on storm overflow activity. 
Storm overflows protect homes and business from flooding by acting as pressure release valves, allowing excess water into rivers and the sea to prevent sewers overflowing during periods of heavy or prolonged rainfall or snow melt. Without them this excess storm water would back up through toilets, drains and manholes. Because of the job they do, we know the majority of what comes out of them is rainwater. 
However, we’ve heard loud and clear from our customers that we need to take action to address them. They are no longer an appropriate way of dealing with an overloaded sewer system. People want to see demonstrable action on how we ultimately plan to consign them to history, and access trusted sources of information about how and when they operate. This is why our proposed business plan for the next five years includes nearly £1 billion of investment to reduce spills and deactivate many completely.  
Making informed choices 
The week, we’ve launched our storm overflow map, which you can find here. The map shows where our storm overflow monitors are located and provides near real time information on any activations.  Updated hourly, it gives customers, stakeholders and those passionate about their local environment, a way to see how our network is operating, so they can make an informed decision about how they interact with their local river or bathing water. 
Using the map 
Using the search function at the top of the map, you can find an address or zoom in on the locations of the overflows. When you pan around on the map itself, click on the coloured icons to see the information about them.  
Getting accurate information about storm spills is not straightforward. In fact, we are the only country in Europe to have installed monitors on our storm overflows. The technology and monitors we’re using is still relatively new – less than five years old – and they are operating in an inhospitable environment (sewer pipes), where glitches can occur, so it’s taken a great deal of work and investment to get the most accurate information in a usable format for customers and stakeholders.    
Because we’ve tried to make this map as useful and timely as possible, it means we are sharing this information almost instantly as we receive it from the monitors. This means there may be times when errors occur, and the sensors are triggered without being caused by a spill.  Through our thorough testing of the monitors and the map we’ve found these glitches can be caused by nearby activity like a high-speed train going past, interruptions in network signal, or even an active spider web!  
Our monitors indicate activations, not definite spills. This is why, if we see a sensor has been activated when we wouldn’t normally expect it, like in dry weather, we send our teams to check the site.  They'll check whether a spill is in fact occurring or if it’s just a problem with the monitors and data. Our fully verified data returns will still be made to the Environment Agency on an annual basis. 
Our plan for Storm Overflows 

We have the lowest level of spills in the industry, but we recognise the need to go further, and work faster, to address public concerns on storm overflows. That’s why we’ve pledged an additional £50 million just this year to tackle even more.  From next year, if our business plan is approved by Ofwat, we will be able to move forward with the significant package of investment we have planned for the next five years.  
Every single one of the 1,471 storm overflows across our network now has a detailed improvement plan that will see discharges significantly reduced by 2050. You can view our plan, and the storm overflow action plans for all water companies in England and Wales, on the WaterUK website or you can read more about our proposed Storm Overflow Action Plan here
For more information on our storm overflows, you can view our FAQs here.  
Visiting the coast this summer 
With the arrival of bathing water season, we’re committed to giving our communities the data needed to make informed decisions about using bathing water. In coastal towns, all of our storm overflows are fitted with monitoring devices that feed data into our telemetry system, ‘BeachAware’.   
Our BeachAware system calculates the volume of storm water being discharged and models each individual to determine if risks are posed to nearby bathing water quality. If a reduction in bathing water quality is predicted, an alert email is automatically generated and sent to the Local Authority, Environment Agency and Surfers Against Sewage who can then communicate this information to the public.  
Whilst any discharges will have been predominantly rainwater, our BeachAware system will notify the Surfers Against Sewage Safer Seas service as a precaution.  We pride ourselves on the health of our coastal and bathing waters and want the public to enjoy all that nature has to offer in our region.  We plan on integrating BeachAware system onto the real time map in the near future to provide greater coverage to our customers. 
On this journey to reduce spills, we’re still learning and improving as we go, with further updates in the pipeline.  We have also committed to a National Environment Hub, which will provide a centralised view of storm overflows across the whole of England and Wales. 
Find out more information on how we are caring for our coastline here