Thame Valley Fisheries Preservation Consultative                            WQR0070


Written evidence submission from Thame Valley Fisheries Preservation Consultative

The Thame Valley Fisheries Preservation Consultative was formed in 1975 when local angling clubs who fished on the River Thame felt that the river was degraded by pollution to the point where anglers catches from the river had fallen to unacceptable levels. It was felt that the cause of the decline in anglers catches was due to poorly performing sewage works that discharged into the River Thame and its tributaries.

It is with great personal sadness that I have to report to you that we find ourselves in exactly the same situation - 46 years later. The reality of this is that the situation has never changed. At times things would improve – which generally followed pressure on Thames Water – either by bad publicity in the local newspapers or by Court cases taken against Thames Water by the National Rivers Authority and its successor the Environment Agency.

There are 33 sewage works that discharge into this small river and its tributaries – which represents around 10% of all the sewage works owned and operated by Thames Water. By far the greatest threat to the River Thame is the very large sewage works at Aylesbury, which discharges into the headwaters of the river. Even today the Aylesbury sewage works is under investigation by the Environment Agency for two breakdowns in 2020 which resulted in 26600 cubic meters of totally untreated sewage was discharged directly into the river on one of the occasions. This was due to the sewage works storm tanks being full, from a storm, some days before. It is alleged that it was a systems failure at the works – which was not discovered until the next morning – a question in itself as to why the Thames Water monitoring failed to set off any alarms. These breakdowns are under investigation by the Environment Agency which may result in prosecution. Over the years there have been several prosecutions against Thames Water, but not all pollutions were prosecuted. You may be aware of the Crown Court case three years ago where Thames Water were fined £20million for severe pollution of the River Thame and the River Thames where the Judge was scathing of Thames Water allowing this to happen and said that it was the equivalent of discharging several super-tankers of raw sewage into the River Thame over a prolonged period during 2012-14. Prior to this pollution there were pollutions in 1979, 1985, 1992, 1997 and 2005 – most of which were due to sewage.

Under such intense pressure from pollution, it is no surprise that the River Thame is a shadow of its former self in terms of fish life. We have tried to restore the river and have stocked over 135000 fish into the river in the last 4years. Most of these were supplied by the Environment Agency fish farm at Calverton. Some were paid for by Thames Water as recompense for the pollutions.          

In addition to Aylesbury, I would mention several other sewage works in my locality including Chinnor Princes Risborough, Thame and Haddenham – all of which discharge poorly treated sewage effluent into a tributary of the River Thame on a regular basis. Indeed, as I sit here writing this, Chinnor sewage works is on South Today news due to sewer flooding into people’s gardens. I have monitored Chinnor on a regular basis and it has been in a poor state for several years now. It has been discharging untreated storm sewage continuously since Christmas. This is due to groundwater infiltration, according to Thames Water. However, the Environment Agency has said that discharging groundwater infiltration as storm sewage is illegal – something that we will be taking up with the EA. The EA are currently investigating a pollution form Chinnor sewage works which occurred in the last two weeks.

So in summary we have a river, that should be a good coarse fishery, which has been decimated time and time again by sewage pollutions – and these are the result of failures by Thames Water to invest in their sewer network. We have many of Thames Water’s sewage works on the River Thame that are in dire need of investment – but there are other rivers under similar pressure including the River Windrush, River Coln, River Glyme and River Evenlode. In short this is a national problem that has to be fixed. What an example we set to the World in the year that we are hosting COP26.

What are the best indicators for river water quality that could be used as targets being developed under the Environment Bill.

With the improvement in technology, it should be possible to set targets (and monitor) elements that are present in sewage effluent such as ammonia. Also, the effects of sewage effluent on the receiving waters should be monitored such as dissolved oxygen. Another major element that affects receiving water is poor turbidity. With the threat that the sewage works pose, I believe that the monitoring of sewage discharges should be removed from the Water Utilities. It has been proven that they cannot be trusted to reliably carry out test and report the results to the EA. The EA should insist that each large sewage discharge point is fitted with a water quality monitor that reports back directly to the EA – Thames Water should not be part of this monitoring.

The number of different types of fish and invertebrates present is another measurable that give good data on the health of a river. An active fish and invertebrate survey programme used to be carried out by the EA – but this has been cut back due to the cuts in funding. This must be supported by a much more active Environment Agency that is adequately funded to carry out this work. The Environment Agency funding has been an easy target to cut over many years. If the Government is serious about looking after the environment, then it has to invest much more money into the Environment Agency.     

How could drainage and sewage management plans, introduced by the Environment Bill, play a role in reduced sewer discharges.

I don’t believe these will have much effect unless the Water Utilities tackle the issue of groundwater infiltration into sewers, which is the current cause of much of the storming events at lots of sewage works. The Water Utilities have to seal their sewers to stop this ground water reaching the sewage treatment cycle. In addition to sorting out the groundwater infiltration there has to be a step change in the amount of storm storage that sewage works have to build into their sewage works. Currently there is about 4 hours storage – which is pitiful in current conditions. If Climate Change has the expected effect then more intense storms are going to occur in the future.

How adequate are the monitoring and reporting requirements around water company discharges.

All CSO discharges must have monitoring installed where they discharge to the river or stream. The Environment Agency should have instant access to the reporting. Event Duration Monitors have given us an invaluable tool in seeing how often these discharges take place and for how long – and the figures are truly shocking. Every CSO discharge should be reported onto a Public Register so that it is very clear if the Water Utilities are avoiding  investment by pushing out poorly treated sewage under the storm discharge allowance.



If a Water Utility uses tankers to remove sewage from works that are overloaded this should be reported to the EA with the name of the sewage works, the quantity removed by tanker and the destination sewage works. Tankering from an overloaded works to a sewage works that is storming should not be allowed.

There is a great deal of benefit in improving our rivers and countryside – an issue that has been very evident from the number of people who are taking more notice of the World around then by going for walks while under Covid restrictions.

Please ensure that this opportunity to bring our rivers back to good ecological status is not wasted.





Dave Wales


Thame Valley Fisheries Preservation Consultative                                          


February 2021