Analysis

Over the past two years, the coverage of the wastewater industry in England has been pretty much the centre of the headlines.

Never have storm overflows had as much attention as they have had during this time period. The water industry has been quite clearly put in the firing line and blamed for the woes of our river environments.

It is clear that our rivers are in poor condition and the UK is firmly on course for regaining its title as ‘the dirty man of Europe’, with polluted waterways and a lack of freshwater bathing. However, how have things changed? How have things become so bad so quickly? The truth is that they haven’t; the water industry is just monitoring a lot more than it ever has in the past.

So, what caused this problem in the first place?

The UK sewerage system – before changes were implemented in the 1970s – operated as a combined gravity system, meaning that both foul water (sewage) and rainwater used the same pipes, directing all the flow to wastewater treatment plants for treatment. This has the benefit of flushing debris that collects in the sewer down to the plant so it can all be treated. As a result of having a combined system, there is a need for a relief valve, should the volume of flow become too high. The relief valve is a ‘storm overflow’ and should only be used when sewage is so dilute that it is practically rainwater.

The argument is that these storm overflows are being used far too frequently and the quality of river waters is consequently very poor. This can be seen in the report written by the Environment Audit Committee, published in January 2022.

This shows that our rivers are not in a good state, particularly with regards to the biological status and the levels of phosphorus. The root cause of this has been firmly blamed on storm overflows as well as agriculture.

So, why the interest in storm overflows?
Firstly, in 2013, Richard Benyon – then the Minister for Natural Environment and Fisheries – directed water companies to monitor the vast majority of storm overflows. This was both the first time the policy had been released and the first time that storm overflows were monitored. All the work to monitor overflows was done within the last asset management period (from 2015-20), and when the results started to become known, there was a realisation that the way the wastewater network operated was less than ideal.

The monitoring showed that in 2020 there were over 400,000 overflows from the sewerage network, decreasing by 8% to 372,533 in 2021. Of course, this data is not for every consented overflow in the country and does not include the unpermitted overflows that have been raised in recent television programmes (Dispatches, August 2022).

So, what is the solution to the pollution crisis in rivers of the UK?
Firstly, there needs to be a reduction in the use of storm overflows by water companies. The wider water industry already recognises this.

Another solution might be investment in the issue and improved monitoring. DEFRA has released the storm overflow reduction programme, which has identified the need to invest over £56 billion over the next 25 years, as well as the need to monitor overflows up and downstream of discharge points, in line with Section 82 of the Environment Act.

However, all of this seems to be too little over a very long timescale, particularly given the current financial crisis. Yet unfortunately, if not resolved relatively quickly, the environmental cost will outweigh the financial cost. This is the balance that must be considered. What is sure is that the state of rivers in the UK will not move forward without some decisive action being taken.