AGM and Annual lecture 20 March 2023 6:30pm-9pm

We are delighted to say that David Aldridge, Professor of Zoology, of St. Catharine’s College, has accepted our invitation to be our speaker on 20 March.

This is an in-person event, in the  David Attenborough Building, Pembroke St, Cambridge CB2 3QZ

We look forward to hearing how his ideas may apply to the Cam system.

David’s work focuses on applied freshwater ecology, with emphasis on bivalve molluscs. His particular interests are the conservation of rare species and threatened ecosystems, the biology and control of invasive species, and the use of biological processes to develop sustainable remediation and monitoring programmes for degraded waterbodies.   A considerable part of his work involves collaboration with the water industry, government agencies and NGOs, and these collaborations provide a significant part of his research funding. 

Download details here

Visiting: To get to the David Attenborough building, enter the site through the Pembroke Arch on Downing Street and continue straight past the Museum of Zoology. There is lift access opposite the bike racks. Contact CCI for more information.

Picture : Keith Heppell

Help shape North East Cambridge

Interesting free “festival” happening this weekend (Saturday and Sunday) to help shape the environmental aspects of the plans for the current sewage works site, ie North East Cambridge

Looks like an interesting opportunity to meet with the developers’ sustainability experts, to learn and influence the development

U+I and TOWN, together with Anglian Water and Cambridge City Council, will host a weekend festival of talks, workshops and family activities to help shape plans for the Core Site, North East Cambridge.

The event will take place on Saturday 29th October between 10am – 5pm, and Sunday 30th October between 11am – 4pm and you can drop in whenever you wish. 

Extracts from the programme

1pm Saturday Workshop: Design a neighbourhood fit for the future: Join Useful Projects to discuss building a neighbourhood at the Core Site that is fit for this and the next century.

2pm Saturday ‘Living alongside nature’: LOLA, the Core Site Landscape architects, will discuss landscaping principles and how we actively design for nature.:

3pm Saturday Workshop: Design a place where humans and nature thrive: Join LOLA landscape architects and Kjellander Sjöberg architects to explore how we can create places where both humans and nature thrive

4pm Saturday Workshop: Design a water conscious place: Useful Projects will present approaches to minimising water use as part of a holistic approach to sustainable development

Details and booking here

New tool for removing Himalayan Balsam

June and July is the time to remove the invasive Himalayan Basam, when the plants are easy to spot, but the explosive seed heads haven’t yet formed.

It looks pretty, but spreads rapidly along rivers and crowds out everything else. We’re working with the Wildlife Trust to remove it from Bourne Brook, Byron’s pool, and a few other spots, before it infests all of Cambridge.

It needs to be removed cleanly from the base, either by pulling it up together with its roots, or cutting it off below the first node.

We’ve discovered that a pruning saw on one of our telescopic Wolf Garten rake handles works really well!

If you would like to join a working party and help, do contact us.

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.

OFWAT requires water companies to reduce sewage overflows

OFWAT have just sent a letter to the chief execs of all water companies, instructing them to publish specific plans to reduce the harm from storm overflows from Sewage Treatment Works before the end of April 2022.

David Black, Interim Chief Executive of OFWAT says: “To achieve this change in performance, I expect companies to publish their plans, for their customers and the wider public to see, to reduce the harm to river water quality from their activities including those caused by storm overflows. This plan should be specific about the actions you will take, including their impact and time frames for delivery for the period to end of March 2025. To ensure early action and engagement, plans should be published before the end of April 2022. This plan should be seen as an opportunity to give the public confidence that companies are proactively taking steps to address these important issues

He comments that the water companies are required “to understand their impact on the environment and human health and be able to measure and monitor their progress in addressing these impacts.”

Cam Valley Forum looks foward to seeing Anglian Water’s plan, and will be sharing our views on whether it’s adequate to “give the public confidence”

CVF Annual Lecture and AGM: 24 March 2022

If you were unable to attend, here are the presentations


The Hall, Storey’s Field Centre, Eddington, Cambridge. This is a 15 minute cycle ride from the Centre of Cambridge, and on the Universal Bus route. IF travelling by car, free parking is available at Madingley Park & Ride, which is a 5-10 minute walk away. More details here

Lecture: Expedition to the Source of the Cam, by Mike Petty MBE

Our most distinguished local historian MIKE PETTY MBE will illustrate James Plumptre’s 1800 account of his walk from Cambridge to Ashwell, supplemented by observations from Samuel Pickwick’s “Cambridge Scrapbook” of 1838. Plumptre’s personal notes are held in the Cambridge University Library. They are the subject of formal research by Ian Ousby in his “James Plumtre’s Britain: The Journals of a Tourist”.

Mike has been the most widely acknowledged authority on the Cambridge area for more than 50 years. He has received the MBE and the prestigious, national T.C.Farries Award for his services. A former Librarian of the Cambridgeshire Collection he is President of the Cambridgeshire Association for Local History. He has published extensively and is a regular contributor to radio and television.

Cam Valley Forum AGM: 6:40pm for 7pm

Prior to the lecture you are warmly invited to the AGM of the Cam Valley Forum at 6.40 for 7pm, in The Studio. If you would like to join the Forum, or become more closely involved with the Forum in any way, please contact the Membership Secretary . The annual subscription for members is £10. Do send us any relevant details of your interests and experience. If a member has a motion they would like to put to this meeting, please email info@camvalleyforum by 10 March.

If members would like to join the management committee, or nominate someone else, please email us at info@camvalleyforum by the same date, including the following information: name of nominee, name of proposer, and, if possible, name of seconder

Raw sewage leak into Bourn Brook

On 11 Feb we discovered a disgustingly smelly leak of raw sewage, flowing into Bourn Brook. It was probably coming from a broken underground sewage pipe between Caldecote and Bourn Sewage Treatment Works.

Our volunteer says:

I was taking a water sample from Bourn Brook for a CVF phosphate project on Wednesday afternoon and noticed a muddy and wet patch on the headland  in a field of cereal opposite my sampling point.  This close to Main Street bridge just within the Caldecote boundary.  There was no water flowing from it.  A sign on the gate into this field had P.X. Farms Ltd, Caucote Hill.  It was obvious that there had been recent water movement from the patch down the bank and into the Bourn Brook.  I assumed it was surface water collecting off the field which slopes towards the Brook.

I was passing there this afternoon and took another look.  At 4.52pm water was gushing out of the headland patch, with two geysers reaching 10cm high, and a considerable amount of water was entering the Brook.  It smelt of sewage from the road bridge, and closer to it there was surface scum, a stronger sewage smell and some cloth and plastic looking wipes.  The distribution of these materials around the edge of the patch suggested that at some previous time the upward flow out of the ground there had been stronger

I phoned the AWS number at 4.54 and reported in the incident and was told that someone would visit within four hours.  After 10 minutes the gushing stopped, and it was not gushing at 5.45.  There is a AWS pumping station 100m away, and the headland patch is roughly in a line towards Bourn STW from it.    

I believe that this overspill has been occurring intermittently for at least two days.  Unfortunately my photos don’t show the spill well.  A grey-brown plume in the water from the entry point looks like soil.  

Raw sewage from flowing from broken sewage pipes is likely to be one of the reasons why the results of our tests for faeces in the Cam were so bad last month.

This this sort of thing is happening all the time. It must stop.

Grantchester Meadows restoration project

Cam Valley Forum is pleased to be collaborating with the local Wildlife Trust and the Farming and Wildlife Advisory Group on an exciting pilot project to restore heavily eroded areas of the Grantchester Meadows river bank.

The project has been offered a total of nearly £10,000 in funding, so long as the community can match this, and so long as we can complete the work before the end of March 2022.

Do join us in supporting this project, using the “Donate” button here

Read more about the Grantchester Meadows Project

Grantchester Meadows River Bank 3 - Ruth Hawksley
Grantchester Meadows – C. Ruth Hawksley

The Grantchester Meadows Riverbank Pilot will address some of the severe erosion to the banks of the River Cam at Grantchester Meadows. Use of the banks by cattle, people and dogs has led to bank erosion, removal of marginal vegetation and silt inputs to the river, which can impact on water quality. Areas of cattle trampling adjacent to footpath gates has also created safety issues, particularly noticeable in winter. 

The project will create two new “cattle drinks” – gently sloping access points to the river with a hard stone base – so that cattle can get to the river safely while reducing erosion and siltation. Soil from the work will be used to repair banks next to the footpath, which will then be protected with a short stretch of fence.  Marginal vegetation is expected to thrive in these areas, providing refuge for water vole, waterfowl and invertebrates. The aim is to trial ways to rebuild and protect the banks using natural materials, and to learn lessons which can be applied to other areas of Grantchester Meadows.

Please consider making a donation to support this vital work to protect the riverbanks and keep Grantchester Meadows special. This work is being conducted by the Wildlife Trust, in collaboration with Cam Valley Forum and FWAG East on behalf of the landowner.

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