AGM and Annual lecture: Monday 18 March 2024 7pm-9:30

David Attenborough Building (Seminar Room), New Museums Site, Downing Street. CB2 3QZ

  • AGM 7pm
  • Refreshments at 7.30pm
  • Annual Lecture 8.00pm

Annual Lecture: Can the Cam Flourish Again?

Can we transform our water infrastructure and farming so we become part of a healthy aquatic ecosystem?

Professor Simon Spooner.

As AtkinsRéalis Fellow Simon is developing nature-based catchment solutions to flooding, water quality, water resources, biodiversity and carbon sequestration.

“Through the centuries we have been reaching ever further upstream for fresh water and dumping our waste as close to our doorstep as we can get away with.”

In his illustrated talk, Simon will present some innovative approaches to living sustainably with our rivers, focusing on enhancing the water cycle and fostering healthy aquatic ecosystems that are integrated with the land they flow from. This transformation demands a shift in urban planning and agricultural practices, emphasizing small-scale changes and investments by individuals and communities, alongside the necessary large-scale infrastructure projects by governments and corporations.

He will discuss the need for new business models, supportive policies, technologies, and collaborative contractual frameworks to facilitate these changes at the local level, inviting discussion on how we might implement such ideas effectively

What happens after Bathing Water Designation?

If the River Cam at Sheep’s Green becomes “Designated Bathing Water” in April 2024, the Environment Agency would start by monitoring the water quality every week during the 2024 bathing season to decide its official initial classification.  The bathing water season starts on 15 May.

Cam Valley Forum plans to provide a QR code at Sheep’s Green and other local swimming spots, giving a link to these official test results as they’re released (which is roughly once a week) so that swimmers can judge if they wish to swim.

In future years, the City Council would put up an official signboard at Sheep’s Green informing people about the Bathing Water Quality.   

We know from our own monitoring work over the last few years that the level of faecal indicator bacteria in the River Cam means that this initial classification will almost certainly be “Poor”, with “Bathing not advised” (although of course it’s still permitted)

Importantly, when there is Designated Bathing Water with a “Poor” water quality classification, this then acts as a statutory “Driver” requiring the water company to investigate the source of pollution and remedy it.

Anglian Water have confirmed to us that if the River Cam becomes “Designated Bathing Water” they will start by doing a “Source Apportionment” study to understand and uncover the causes of the problem. This will include looking at both their various assets (pipes, pumping stations and sewage works) and other 3rd party sources.

As Cam Valley Forum we will be very interested in the results of this Source Apportionment study.

We all expect that a big source of the problem will be the ageing and overloaded sewage infrastructure at Haslingfield.

Subject to the findings of the Source Apportionment study and approval of Anglian Water’s Business Plan by Ofwat they’re expecting to spend around £5M on improvements at Haslingfield, with work completed by 2027. The details of what needs to be done, will of course depend on what the source apportionment study discovers, but the overall aim is to improve the water quality in the River Cam at Sheep’s Green from Poor to Good

Without the statutory “Driver” of Bathing Water Designation, the improvements would be likely to take much longer…. maybe decades.

It’s going to take a while, but if we get Designation a cleaner Cam is within our grasp.

Do respond to Defra’s consultation by the deadline of 10 March

Defra Shortlists River Cam for Bathing Water Designation

Cam Valley Forum is very pleased that Defra announced on 26 February that Cam Valley Forum’s application for Bathing Water Designation for the River Cam at Sheep’s Green has been shortlisted.  It is one of 27 applications included in Defra’s statutory consultation

Anne Miller, Cam Valley Forum’s lead on this says “We will have to wait a few more weeks to hear if we will be granted designation, but this is a great step forward. A cleaner Cam is within our grasp”

We started working on this back in 2020, and last summer received overwhelming support in our formal consultation, with 517 responses, 93% in support. This included strong support from organisations including Cambridge City Council, Scudamores, Cambridge Canoe Club and the Cambridge Federation of Women’s Institutes.

Our surveys showed that hundreds of bathers enjoy swimming in the River Cam on peak days in summer, although, because the water is cold, one only sees a few people in the water at a time.

Designation is important because we know that the water quality is currently poor, and if Defra approves our application, this will trigger a ‘driver’ for much needed investment from Anglian Water. This investment will focus on understanding the sources of pollution and then (subject to approval by Ofwat) Anglian Water would invest to help clean up the Cam to help make it safer for swimmers.  Ofwat would typically require these improvement schemes to be in place by 2027.

 We know from our monitoring work over the last few years, that the ageing and overloaded sewage infrastructure in the Haslingfield area is a major source of the faecal pollution of the River Cam. This isn’t the only source of pollution of course, nor the only reason people can get sick, but we hope that as a result of Bathing Water Designation, it will become much safer for people to swim in the River 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 allowed 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

Do respond to Defra’s consultation by the deadline of 10 March

How low can we go?

How can we reduce our water use, to help save our chalk streams?

Many Cam Valley Forum members are concerned about the health of our Chalk streams, so monitor their water use carefully. Some are already achieving water use well below average, ranging from 50 to 80 litres per person per day.  This compares to the current average use of around 150 litres per person per day, and the design target for new homes (specified in the draft Greater Cambridge Local Plan) of 80 litres per person per day.

To explore where the savings come from, some members have shared their water usage with us.  We have compared a careful ‘Low Water Use Household’, using around 50 litres per person per day, with a ‘High Water use Household’ using around 180 litres per person per day.

We estimated how much water they were using for different purposes and compared the households, as shown in the chart below.

Both households are 2 retired people living in homes with a garden. Other households may have different water usage patterns of course, for example if they have young children, or do a lot of mucky activities, or they’re out at work a lot of the time. Nevertheless the comparison is revealing.

Although the water efficiency of appliances affects water use, and their installation should be encouraged, the choices each household makes about how it uses water are often more important.

These choices, in order of importance are:

  1. hosepipes,
  2. showers and baths,
  3. the washing machine,
  4. toilets.

We looked at why the 2 households were using such different amounts of water for each of those key activities.

The Hosepipe. This is the most important differentiator, using about 170 litres in 10 minutes. This is why, even in summer the careful Low Water Use Household will very seldom use the hosepipe, typically instead collecting rainwater and water from the washing up (they do not use a dishwasher). This is then used for cleaning or to water the garden, as shown in this short video  

In contrast the High Water Use Household typically uses a hosepipe for 10 minutes a day in summer. Even in this short period the hosepipe nearly doubles the household’s water consumption, using more in 10 minutes than the Low Water Use Household uses all day.

Showers and baths are typically the second biggest differentiator between low and high water users. A modern water efficient shower head typically uses around 7 l/min. The two person Low Water Use Household shown in the graph takes 2 short showers per day, together totalling 5 minutes.   They seldom take baths, which use a lot more water than a shower. 

In the High Water Use Household the showers are estimated to take twice as long, at a total of 10 minutes a day for the 2 people. This consumes three quarters of the water that the Low Water Use Household uses for all purposes. If the High Water Use Household had a power shower or took regular baths (which can easily use 80l per use) their water use would be even higher.

The washing machine.  A typical modern, water efficient, washing machine uses around 43 l/load. The Low Water Use Household tries only to use the washing machine “when needed” which results in typically running one load per week. 

In the High Water Use Household, clothes are washed more or less every time they’re worn, resulting in the washing machine being used daily. As the graph shows this consumes half the water that the Low Water Use Household uses for all purposes in a day.

Toilets are the 4th most important differentiator.  While each flush of a modern low flow toilet uses around 4.5 l / flush (a tenth of the water that an old fashioned one uses) households make very different choices about how often they flush.  Typically, the Low Water Use Household only flushes “when needed” adopting the principle “if its yellow, let it mellow, if its brown, flush it down” flushing around 6 times a day.  

The High Water Use Household also has a modern low flush toilet, but flushes every time, estimated at around 10 times a day.   This simple choice means they flush away nearly half the water that the Low Water Use Household uses for all purposes.  Their water use would of course be much worse if they were also using an old fashioned toilet with a big cistern, which could use as much as 30l per flush.

As this shows, although owning water efficient appliances helps us reduce consumption, our personal choices usually make a much bigger difference.  Those using less than 80 litres per person per day can probably feel that they’re doing their bit to help save the Chalk streams.

Photo: Wild Trout Trust, Hoffer’s Brook Chalk Stream

However, it’s not sufficient to rely on the good will of a minority to help save our Chalk streams. This is why Cam Valley Forum is calling for Cambridge Water to introduce hosepipe bans (a.k.a Temporary Use Bans) every summer.

A senior Environment Agency manager has told us they are “surprised and disappointed” that Cambridge Water has not already introduced these.

If you’re not sure how to track your water usage, read this short article

How to track your water usage

If you don’t already have a water meter, ask your water company to fit one. This is free and typically reduces your bills by around £100 p.a. This is because those without a meter are assumed to be very high water users, and so the rates are set accordingly.   

Once you have had a meter installed (or you’ve found the one you already have, which will probably be near the stopcock for the house) the simplest way to see your water consumption is to look at your water bills. 

This will tell you what period the water consumption was measured over and give your water consumption in m3. You can then calculate the water consumption per person per day. Note that a cubic meter is 1000 litres. 

In the example given, the water consumption of the household is 20m3 x 1000 /185 days = 108 litres per day.  As there are 2 people in the household, this is 54 litres per person per day.

If you want more detail, you can read the meter.  It will probably look something like this:

This is showing a reading of 1071.81 m3 (look at the digits and ignore the dials) If you read the meter regularly and note the dates, you will then be able to plot a graph to see how your water consumption varies during the year.  

Here’s an example from one of our members.

They point out that their water use increased during the Covid-19 pandemic (as it did for many) and that it can rise over the Christmas period, when family members come to stay.  Nevertheless, their water use has never exceeded 100 litres per person per day and is generally around 50-60 litres per person per day. This is around 1/3rd of the average use, so they feel good that they’re helping save our Chalk streams.

To explore how people are reducing their water use, read our short article

More tea vicar? An unsavoury incident.

Cam Valley Forum hunts down a source of pollution in Vicars Brook

You’ve probably heard of Hobson’s Brook, the famous chalk stream which becomes Hobson’s Conduit as it approaches Cambridge towards the Botanic Gardens. However, fewer people know about its offshoot sibling, Vicar’s Brook.  It’s a charming little crystal-clear chalk stream that is supplied by water from Hobson’s Brook at two places.

Vicar’s brook, south

It runs alongside Empty Common allotments, through a long tunnel under the Trumpington Road/Brooklands Avenue crossroads, and continues along the side the Coe Fen cycle path, before emptying into the River Cam at Hodson’s Folly.

Vicar’s Brook, north

Shoals of silvery dace and roach, a hundred strong, can be seen dancing under the water surface.

But water clarity can deceive; invertebrate abundance and variety are not good.

Every few weeks, since May 2023, we have been sampling the brook at seven locations in the search for pollutants which could be responsible for the low invertebrate counts. There are numerous outfalls, several of them more than a foot wide, feeding into the brook.  Could any be polluting this beautiful stream and affecting its aquatic life? Samples are collected at regular intervals, or when a weather event occurs which may affect the flow of the stream and the outfalls which feed it.  These are analysed back at the CVF laboratory (a re-purposed dining room table in a house in Cambridge) for phosphate and E. coli.  

The CVF lab (a.k.a Richard’s kitchen)

Phosphate concentration is a key indicator of chalk stream health; high levels cause the stones and gravel to become coated by ugly filamentous algae. Sources include detergents (such as car shampoo), fertilizer use and sewage. A pristine chalk stream should contain no phosphate. E. coli on the other hand is an indicator of only one thing – animal poo, including human.  Measuring E. coli is actually pretty simple.  One millilitre of brook water is spread across the circular part of a E. coli specific petrifilm.  Incubating the films overnight allows the E. coli colonies to grow and reveal themselves as blue dots.  Ten blue dots on a petrifilm is equivalent to 1000 cfus/100 ml above which faecal pollution levels are considered “elevated“, potentially resulting in bathing water quality being designated as “poor”

Test samples from Vicars Brook on 21 November 2023

The blue dot count on the morning of 21 November 2023, however, turned out to be a real shocker, with the samples from points 5,6 and 7 way above the limit.

On seeing the result, our CVF sampler immediately trotted back to investigate the brook between sample points 3 and 5. It didn’t take long to identify the culprit; the outfall from the Brooklands Avenue surface water sewer was producing a very milky-looking effluent.  E. coli analysis of this outfall showed over 500 blue dots!

Brooklands avenue outfall, under normal conditions

We wanted to know the source of the E. coli. Although we’d previously bought a drainage map showing the surface drains and sewers in the area, the source of the pollution wasn’t clear. The best option was to report it to Anglian Water.  Pleasingly, within an hour of our phone call, AW technicans had arrived at the outfall and samples were being analysed using a handheld on-the-spot ammonia meter. Ammonia is also an indicator of sewage effluent. Although the milkiness had dissipated by then, the ammonia levels were still very high, much higher than surface drain water should be.

We spent the next few hours accompanying AW staff as they lifted manholes, diligently sampling and analysing as they moved along Brooklands Avenue. The probable culprit was finally identified as a construction works along Clarendon Road (most likely a misconnected portable toilet).  AW promised to resolve the source of the pollution. Several days later CVF was informed that re-sampling at the outfall had shown zero ammonia levels, indicating that action had been taken to resolve the leakage.

Do take the time to explore our lovely Vicar’s Brook, and look out for the shoals of dace and roach as you go, but do keep your eyes, and nostrils, open.  It needs looking after, and citizen science really can make a difference. 

To get involved, join us!

CVF at Gretton School, Girton

Michael Goodhart and Bruce Huett from Cam Valley Forum visited Gretton School in Girton, Cambridge on 12th October 2023 for a full day to explore the nature of chalk streams with the pupils as part of their sustainability week.  The day was organised by the sustainability teacher Yair Doza and the acting head of science Jenny McCran also participated.

Gretton school is for children with Autism from aged from 7 to 19 from Cambridgeshire and wider afield.  It has about 140 pupils of differing abilities, some as boarders and others as day pupils.

Four sessions were held in the science lab.  Bruce used a powerpoint to elicit responses from the children on their experiences of rivers and chalk streams. He explained how he was involved with a river group that had made significant changes to the river Mel in Melbourn, Cambridgeshire.  One of the pupils lived in Meldreth and was able to recount his experiences of playing near the river.

Water Crowfoot in River Mel. Bruce Huett

Using slides depicting animals and plants in the river he explored how it was important to maintain a healthy river environment to support biodiversity.  The children enjoyed the reference to Ratty, the water vole from Wind in the Willows, and were concerned about the threat to them from predators if water levels dropped.  This linked into a discussion of food chains and the role of otters. Otter spraint – a small deposit containing fish bones that otters leave on rocks to attract females has been found in the Mel and interested the pupils.

Some pupils had enjoyed seeing kingfishers and some had encountered leeches, including having their blood sucked.

The Hach kit was used to demonstrate phosphate levels in water, giving a blue colour if phosphate was present.  Luckily the distilled water didn’t turn blue but Mel water, from below the sewage works, did.  However, surprisingly this was lighter than a sample from Byron’s pool.

Bruce also brought samples of gravel and soft chalk from the base of the Mel to illustrate how the base of the river was formed.

With some classes there was brief discussion on the spirituality of water and the many types of water gods and forms of spring, river and water worship around the world.

Leisure activities in and on water were explored and Michael talked about and showed pictures of his experience of learning to swim in the Cam.  Bruce confused one of the pupils when he asked about which stroke he liked to use.  He thought it was about stroking a cat!

Michael explained the idea of designating a stretch of the river for bathing.

He also raised the issue of the declining level of water in the streams and the problems of abstraction, over use of water and climate change (illustrated by a slide of a completely dried up Mel).  This led into discussions on how we could reduce the amount of water we use, with interesting suggestions from the children.  The dangers of flooding were also mentioned. 

River Mel 2012. Bruce Huett

There were a lot of questions from some of the pupils and this kept Michael and Bruce on their toes.

The school was very appreciative of their efforts and it was an opportunity to widen the profile of Cam Valley Forum and raise chalk stream issues with a new audience.

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