Tag: River Cam

Sewage Sleuthing the River Cam

Why is the Bathing Water quality so poor, and what should be done about it?

We held a well attended event in Newnham, Cambridge on 23 October 2024 to share the results of our investigations into the poor water quality in the River Cam, at the end of the first Bathing Season after achieving Bathing Water Designation.

Sewage sleuthing presentationDownload the slides here

Following the Environment Agency’s monitoring , it is clear that the official Bathing Water classification will be “poor”. This will trigger advice against swimming, investigations into the causes, and measures to fix them.

We’d expected a poor classification, but the results are shocking: every single E. coli test result is above the 90 percentile threshold of 900 colonies/100ml. The River Cam may well have the worst quality Bathing Water in the UK

Environment Agency Monitoring results for the River Cam, 2024 Bathing Water Season.

We want correspondingly urgent action to improve it, to protect the health of the many people that swim, kayak, paddleboard, punt and row on the Cam.

Our analysis of detailed monitoring done for us by Anglian Water during 2022-3 shows that Haslingfield Sewage works, 4km upstream is a big part of the problem. In summer, E. coli levels peak at the Sewage works, then steadily decline as the river flows past Grantchester Meadows to Sheep’s Green. In winter, and after rain, levels of E.coli are much higher, and they remain high as the water flows downstream

E.coli levels peak at Haslingfield Sewage Works, then steadily improve downstream towards Sheep’s Green

But our investigations show that other causes may also be contributing: its not JUST the sewage works.

These include frequent overflows from the sewage pumping stations in Harston, Haslingfield and Grantchester. These releases flow into various ditches, and then into the Cam

Dilute sewage in the street at Button End, Harston

The Rising Main (the pressurised pipeline taking raw sewage from the surrounding villages to Haslingfield Sewage Works) burst 3 times in 2022 and once in 2024

Raw sewage flowing from a burst Rising Main between Haslingfield and the Sewage Works in 2020

These various overflows have released sewage 35 times since January 2021.

This is in addition to the all too frequent overflows from the sewage works itself, which last year was revealed by Anglian Water’s EDM report to have been overflowing 30% of the time.

Surface water from Newnham Croft flows into the ditch at Paradise Nature Reserve. We think this may be also be contributing when it rains…

Newnham Croft surface water outfall into the ditch at Paradise Nature Reserve

After rain, the ditch goes brown. We’ve tested this for E. coli and as our presentation shows, after rain, E.coli levels reach 100,000 colonies/100ml . This shockingly high level is as bad as in the effluent being discharged from Haslingfield Sewage works.

We don’t yet know where this is coming from. Misconnections in Newnham could easily be a cause, because these are quite common, particularly from extensions when builders take “shortcuts”. These misconnections could be releasing sewage, or other “foul” water into Paradise Nature Reserve and the River Cam.

Dog mess might also be contributing.

A likely misconnection in Newnham Croft, with foul water pipes going into a rain water gulley

To help

  • Check that builders haven’t misconnected your drains (contact us if you want help)
  • Call the Environment Agency, immediately on 0800 80 7060 if you see suspected pollution incidents (this “evidence” helps the Environment Agency’s enforcement)
  • Never, ever, put wet wipes down the toilet (these cause blockages)
  • And join us on the ‘March for Clean Water’ on 3 Nov (show your support for tighter regulation, better enforcement and an end to pollution for profit)

We’ve organised a coach from Cambridge to the ‘March for Clean Water’, or you can make your own way by train. Do join us

Reserve your place on the coach here:

Sewage sleuthing presentationDownload the slides here

Dramatic increase in Sewage spills into River Cam

The recently released data on sewage overflows shows a shocking increase in the reported discharges from Cambridge City and Haslingfield Sewage Works.

During 2023, the aging and overloaded sewage works at Haslingfield, 5km upstream from Cambridge was spilling sewage for 3000 hours, in other words for 34% of the year.  Cambridge Sewage Works, just downstream of the city, was spilling sewage into the river where our boat race crews train, for 17% of the year.

As the graph below shows, both were dramatic increases from previous years.

We have asked Anglian Water what is going on

Their website says

“Our EDM monitors and investments are helping reduce spills and have moved the dial in the right direction. Spills would have been considerably higher without it. However, it is important to acknowledge the exceptionally wet weather we had in 2023, particularly late in the period, which meant that 70% of our spills were in Q4 alone and in stark comparison to the extremely dry year in 2021, as climate change continues to result in more extreme weather events.”

On 9 April 2024, they informed us that at Haslingfield “the EDM point (ie the sensors that detect a spill) was modified a year ago in an attempt to reduce impacts from standing water whilst ensuring that we did not miss spills.  However, it has become apparent that following prolonged periods of wet weather that standing water can rise to reach this probe, therefore further modifications are being assessed”    

When Cam Valley Forum visited Haslingfield sewage treatment works in 2022 we were shown these sensors, which had been relocated from their previous position in September 2021. Subsidence had meant that in the previous position they were sitting in a puddle, rather than recording spills. It’s disappointing if they’re still not correctly positioned to give meaningful results.

It is true that late 2023 was wet, but to assess how exceptional this is, we have looked at the Met Office weather data for Cambridge, which has been monitored at NIAB (the National Institute for Agricultural Botany) every year since 1959.

The rainfall data shows that in 2023 Cambridge was a little wetter than the previous few years, but there only seems to be a vague relationship between the annual rainfall and the duration of sewage overflows during the year. 

The slightly higher rainfall in 2023 in comparison to 2020 doesn’t seem sufficient to explain the dramatic increase in sewage spills. So what’s going on?

The Met Office rainfall data for Cambridge, shows that March and October 2023 were both very wet, which might have been expected to create problems. But these 2 wet months can’t excuse Haslingfield Sewage works spilling sewage for 34% of the year.

Water companies are allowed to spill sewage into the river when conditions are “exceptionally” wet, but the definition of “exceptional” is unclear.

Looking back over the last 65 years, months as wet as the wettest months in 2023 have happened at intervals, but were they “exceptional” enough to make it legally permitted for Anglian Water to spill sewage into the River Cam?  We’ll leave that question for the lawyers to answer. 

However, as the longterm graphs show, Climate Change is making weather that was once “exceptional” seem “normal” so our water companies need to be urgently upgrading the infrastructure to cope.   This applies both to our sewage infrastructure, which in Cambridge is the responsibility of Anglian Water, and fresh water supply, which is the responsibility of Cambridge Water.

Cambridge’s wettest months seem to be becoming more frequent and wetter, and the rate of increase might itself be increasing. (In the graphs above and below, the longterm trendlines are shown by red dashes)

Winter rain doesn’t eliminate the risk of the summer pain from drought.

The same NIAB dataset shows that the average monthly temperature in Cambridge has risen by about 3C since the 1990s.  Winter temperatures have increased even more dramatically: they are now around 6C higher than during the freezing cold winters of the 1980s. This is probably mainly due to climate change, but Cambridge’s increasing urbanisation may be contributing slightly.

These changes increase the risk of drought and of plant pests surviving the winter, while significantly changing our natural habitats and the species that can live here.

They also increase people’s desire to swim in the river, which is another reason why we want our water companies to make the necessary investments so that sewage spills become truly “exceptional” events.

Underlying everything is the growing threat from climate change, so we all need to take urgent action to reduce our contribution to the problem by cutting our carbon emissions. Unless we do, no amount of investment will be able to prevent the horrific consequences.

Cambridge City Council formally supports Bathing Water Designation

We are delighted that Cambridge City Council will be supporting our application to Defra for Bathing Water Designation for the Cam at Sheep’s Green

This followed consideration by the City Council’s Environment and Communities Scrutiny Committee on 5 October, at which Councillors voted, 7 to 1, to formally support an application for Bathing Water Designation for the Cam at Sheep’s Green

We can now finalise and submit our application.

Anne Miller, Cam Valley forum’s lead on this says “I’m so pleased, and grateful for the hard work of everyone who has helped, since Jean Perraton and  Michael Goodhart started working towards bathing water designation back in 2020”

We are very hopeful that Defra will approve our application, and that this will unlock at least £5 Million in much needed investment from Anglian Water to help clean up the Cam. We know from the monitoring work over the last few years, that the aging and overloaded sewage infrastructure in the Haslingfield area is a major source of the faecal pollution of the Cam. This is resulting in such poor water quality that swimmers at times get sick, and it contributes to the phosphate pollution that is so damaging to habitats and wildlife. ”

“The investigation and improvements won’t happen overnight, but we hope that within a few years, it will be much safer for people to swim in the Cam” 

Michael Goodhart said “The Town Bathing Place at Sheep’s Green has a history going back several hundred years, as a place where people could swim.  Back in the 1960s my family would picnic and catch tiddlers along Rush and float rafts in the paddling pool.  I was taught to swim in Snob’s Stream, before being allowing to dive into the main river Cam.  I still love swimming in the river Cam, as do so many people.  Bathing Water Designation provides a major opportunity for improving the quality of the river water for swimmers, boaters and also, very importantly we hope, for wildlife. “

Sheep’s Green in the 1970s

About bathing water designation for the Cam at Sheep’s Green

Cam Valley Forum will be applying to Defra for Bathing Water Designation for the Cam at Sheep’s Green, to improve the health of swimmers and help clean up the River Cam.

Summer evening at Sheep’s Green

Importantly, because the water quality is very likely to be offically rated as “poor”, designation should get us the investment we need to help clean up the river.

We are pleased to see that Anglian Water’s business plan, published on Monday 2 October, confirms this.  In it, on pages 174-6, they say that IF the Cam gets priority, by becoming “Designated Bathing Water” they are budgeting ~£5M to improve Haslingfield’s ageing and overloaded sewage infrastructure. We need this!

However to apply for Designation, we had to have a formal letter of support from the City Council.

Our consultation has shown that designation is overwhelmingly supported by the community. We received 509 responses to our 10 week online consultation, the vast majority from the local area. 93% were in support.  In addition to the City Council, we also have support from 18 organisations, ranging from Scudamores and Cambridge Canoe Club, to the Cambridge Federation of Women’s Institutes and South Cambs District Council.

The most common reason for supporting designation was wanting cleaner water in the Cam to reduce the health risks to swimmers and other water users.

The most common reason given for opposing designation, related to fears of significantly increased visitor numbers and that this would then damage precious habitats.

We share the concern to protect natural habitats, and much of our work is about preserving these. However, the fears of significantly increased numbers of visitors were in part due to rumours that the council would promote it as a visitor destination.  These rumours are incorrect.  Designation is simply about the health of bathers. There is absolutely no obligation to promote it as a visitor destination, so we are pleased that Councillor Sam Carling confirmed this several times during the meeting, and confirmed that the council has no intention of promoting it either.

Defra currently require us to submit 2 user surveys showing an average of at least 100 “bathers” on the 2 busiest days. Sheep’s Green has long been a popular bathing spot for communities across Cambridge, so our 2 surveys averaged more than 3 times this.  However, as few people stay in the water long, we seldom saw more than 12 people in the water at a time.

We think this will have minimal impact on habitats, parks and nature reserves

A fox and paddleboarders watching each other at Sheep’s Green

2023 bathing season record: 478 bathers at Sheep’s Green

A hot, but very pleasant day on Saturday 9 September, counting a total of 478 bathers in 4 hours at Sheeps Green. This is our record for the 2023 bathing season.

We already had two user surveys showing 184 and 278 bathers, which is well over Defra’s requirement of a minumum of an average of 100 bathers in 4 hours, in order to apply for Bathing Water Designation. However, as Saturday was forecast to be the hottest day of the summer, we decided to do another count.

As the afternoon temperature peaked at 32C, it was a joy to be in, on or near the river. We counted 478 bathers (ie swimmers, or children paddling) in just 4 hours.

Kids and adults swim from the quayside

Making a big splash

Teenagers congregate at Hodsons Folly

Small children and their parents enjoy paddling in the Rush

Worryingly, some people believe that the Rush is a fresh water spring (despite the clear notice saying that its river water). We were told someone had even been drinking from it. This is not a good idea (particularly as there’s a drinking fountain near the cafe)

Very pleasant on the grass by the quayside…

and the Sheep’s Green picnic area was peaceful….

while the Lammas Land paddling pool was heaving…

the Cafe was busy..

and as usual, a few people had parked in stupid places.

Successful Bathing Water Consultation Event

We held a well attended and lively consultation event on bathing water designation in Newnham Sports and Social Club on Tuesday 29 August.

Download the presentation here

Ably and fairly chaired by Jeremy Sallis (formerly of BBC Radio Cambridge), the room was packed with 62 attendees. A wide range of views were heard: Friends of the Cam handed out leaflets and spoke powerfully about their opposition to the principle of designation and their outrage at Anglian Water. Others spoke equally powerfully about the benefits of designation, particularly for the health of swimmers, Cambridge’s young people and their access to nature.

The main concerns related to increased visitor numbers. DBW would be a minor factor in increasing visitor numbers but there are a lot of other factors related to warming climate and less long distance travel for leisure that are likely to be stronger, given that the designation will result in advisories against swimming until improvements in quality can be achieved. Many people in the audience felt that visitor numbers to all green spaces in Cambridge are increasing and likely to increase for multiple reasons and this is good, and obviously will in the long-term need managing  – but this should not be stopping us cleaning up the river.

The overall feeling of the meeting was supportive of designation.

One participant emailed us with her reaction to the event as follows

“Many local residents came along and put paid to the oft repeated fallacy that local people don’t want designated bathing water at Sheeps Green. The overall feeling was supportive……. every attendee received FotC leaflet, and I felt counterarguments most certainly were heard and given space to be expressed. Overall the takeaway was ‘don’t let perfect be the enemy of good’ – all these local pressure groups can and should campaign on many issues for better river health, changes to environment legislation and designation process, but just because DBWs don’t fix all problems all at once does not mean it’s not worthwhile.“

Michael Goodhart, sharing some of the 400+ year history of swimming in the Cam

Anne Miller, explaining why Cam Valley Forum proposes applying for designation

Simon Spooner explaining how the water industry works

Olwen Williams sharing her concerns for Paradise Local Nature Reserve

Download the presentation here

Do respond to the consultation here by the deadline of 15 September 2023

City Councillors support bathing water designation.

We are very pleased that at the full Council Meeting on 20 July 2023, Cambridge City Council voted overwhelmingly to approve Cllr Katie Thornburrow’s motion (with a supportive Lib Dem amendment) in support of our proposed application for bathing water designation, subject to consideration by the Environment & Community Scrutiny Committee on 5 October.

The key section of the approved, ammended motion included the statement that : “This Council.. Agrees to evaluate the potential of a formal application to Defra for an inland water stretch along the River Cam within Cambridge City Council boundaries to be designated as a bathing site, working with Anglian Water and local partners such as Cam Valley Forum, in order to secure an improvement in water quality while also taking into account the impact of any increased usage and avoidance of significant additional cost; and requests a report on this to the Environment & Community Scrutiny Committee to inform a balanced decision by the Executive Councillor.”

The Environment & Community Scrutiny Committee meeting is at 6pm on 5 October.

We welcome this addition to our consultation process.

Bathers at The Rush, Sheep’s Green cambridge

Why do we want to apply for bathing water designation?

Cam Valley Forum wants to apply for designated bathing water status for Sheep’s Green, because this is the most powerful way we have to improve the water quality in the Cam, for the benefit of swimmers, paddling kids, punters, kayakers, our rowing crews, other river users. We hope that a reduction in sewage pollution will also benefit our wonderful natural habitats. 

The requirements for designation were changed a few weeks ago, and there is some confusion about this, because the DEFRA website is confusing. However we’ve had clarification from DEFRA that they want to see evidence that an average of at least 100 “bathers” a day use the proposed stretch, at least briefly during the peak 4 hours, averaged over just the 2 peak days of the summer bathing season. We are currently gathering this evidence, so you may see CVF volunteers out counting bathers at peak times at Sheep’s Green. Our impression is that, assuming we have some nice weather this summer, the current bather numbers at our proposed stretch (from Hodsons Folly to The Rush) are sufficient to achieve designation.

It is important to note that designation is about protecting the health of existing “bathers” not attracting new ones. The experience of other inland river groups, such as at the river Warfe at Ilkely in Yorkshire is that designation results in no change in visitor numbers, not least because it highlights the “poor” water quality (as we currently have in the Cam)

This “poor” classification then creates statutory obligations under the Bathing Water Regulations 2013 that should accelerate the much needed improvements in Haslingfield sewage works. 

This is why councils and community groups across the country are applying. Sixteen inland sites have already achieved designation, including Wolvercote Mill Stream in Oxford, the River Wharfe at Ilkely, and the River Deben at Waldringfield in Suffolk.  Hundreds of coastal sites have of course, had designated bathing water status for years.

You can see more detail on our proposal here

Do submit your views to our consultation using the form here.

Sewage overflows increasing

The data thats just been released by the wonderful Rivers Trust, shows a concerning and increasing duration of Sewage Overflows from our local Sewage Treatment Works into the Cam and Rhee.

Haslingfield still has a high level of sewage overflows, although this may be due to problems with a sensor being incorrectly positioned. As the sensor was relocated in September 2021, shortly before Cam Valley Forum’s vist, we hope to see a very much reduced duration of overflows in 2022.

Melbourn overflows are increasing worryingly, which maybe explains why we saw very high levels of E-coli in the River Mel just downstream of the Sewage Works when we tested it on 19 January 2022. Anglian Water say this is due to “Ground water inundation”, but the River Mel Restoration Group are right to be concerned.

Concerningly, over the last 3 years, the duration of Sewage Overflows from Cambridge Riverside has been steadily increasing, although from a low level.

New Cam Valley Forum report published

The Cam from Grantchester to Cambridge: A much loved river in need of our care.

This report is an appreciation of the River Cam from Grantchester to Cambridge, outlining the threats it faces and the context and importance of the river.  It illustrates the entire 2.8 miles length of the “upper river”, from Byrons Pool to Kings Mill Weir in Cambridge, and may provide a better understanding of the river’s rich history and precious ecology.  It is hoped that it may motivate more people to want to protect it from damage, now and in the future.

This is first of the documents that has been prepared as part of Cam Valley Forum’s  “Cam Safer Swim Initiative” (CSSI) If you would like to commment on the report, or get involved in our work to make the Cam safer for swimming, contact cssi@camvalleyforum.uk

Cam Safer Swim Initiative

The Cam Valley Forum recently consulted about designating part of the River Cam as a “Bathing Water”. This would benefit river users by prompting work to improve the quality of the water.  Our proposals are here:

cvf_swimming_proposal_informal_consultation

We were delighted to receive 75 responses and have distilled these in a response document:

Responses-to-CVF-Bathing-Water-Proposal

We are now forming a steering group to take forward a ‘Cam Safer Swim Initiative’. Action areas include:

  • Making local improvements at bathing locations
  • Gathering data on recreational use of the river
  • Monitoring water quality
  • Pressing for better wastewater treatment and an end to combined sewer overflows
  • Reducing diffuse pollution from fields and roads
  • Pursuing dialogue with a wide range of interests

If you would be interested in helping in any of these areas, or have any comments and suggestions, please get in touch cssi@camvalleyforum.uk.

Blanket Herbicide Spraying by the Environment Agency

Cam between Littlebury and Little Chesterford, 19 Oct 2019 (c) Mike Foley

We are horified to discover that the Environment Agency is proposing, once again, to blanket spray herbicide along large stretches of our precious rivers and streams.   We object strongly to this, and urge the EA to put their money and resources to better use.

You can see a summary of our progress (or not) below, and a full log here of the reports that we have received of damage caused by blanket herbicide spraying

Update  26 June 2020

We understand that discussions are ongoing in the Environment Agency and hope for a positive outcome.  In the meantime we would welcome any further views and evidence from river users to help us press our concerns home and ensure that the funds earmarked for spraying are instead used for positive work to enhance our rivers.

Update 4 June 2020

In early June, we were horrified to discover that the Environment Agency is proposing, once again, to blanket spray herbicide along large stretches of our precious rivers and streams.   They say this is “to maintain sinuosity within the channel to help reduce flood risk”

You can see the full list of sites here:EA herbicide proposals 2020

They sent this out for consultation to selected key conservation organisations a few weeks ago, with a deadline for responses of 5 June. However, as many staff are on furlough, it has only just come to our attention.

You can read our formal consultation response here