Blog & News

Wet wipe monster

A group us from Cam Valley Forum had a fascinating visit to Cambridge’s Water Treatment works (also known as as the sewage works), run by Anglian Water near Milton. Two aspects of the visit stick in my mind.

The wetwipe monster

Never ever flush a wetwipe down the loo ….  despite vague statements on the packaging about being “flushable” they aren’t.

This photo shows just a few of the 4 tonnes a day of disgusting wetwipes that Anglian Water staff have to fish out. The problem is that wet wipes are made of plastic so they don’t degrade, and they aren’t even recyclable. At worst, if they get mixed up with meat fat in the drains, they can turn into massive fatbergs that clog the pipes.

Why use wetwipes anyway?  Many people find that using a small reuseable cloth and water from the tap works just as well. However, if you do need to use them, put them in the bin.

The power of poo-power. 

We were also impressed that 40% of the energy used by the treatment works is poo-powered, thanks to a big anaerobic bio-digester that turns the treated poo into fuel gas. This is burnt in engines to provide electricity for all the pumps they use to treat up to 1300/second of water and sewage. Any surplus power is exported to the grid to be used in people’s homes.

The dry crumbly non-smelly solid material that comes out of the bio-digester is  mostly sold to sugar beet farmers for improving the soil.

Successful Pennywort pulling working party on 8th July

On a glorious summer day,  21 participants joined us for the pennywort pulling working party, supported by funding from Cambridge Water’s PEBBLE fund.

With fantastic help from Cambridge Canoe club and their members, we had a fleet of 11 canoes out on the river, plus a team working from the bank in Grantchester Mill Pond.

We started with some instruction from Mike on Floating Pennywort, and how to distinguish it from other plants, using a handy patch in the nearby Snobs stream.

We then headed out on the river to find and clear the emerging strandsWe surveyed the whole river, from Mill lane, Cambridge to Grantchester Mill Pond, and removed virtually all visible pennywort.  There were just a few strands identified and left, to be dealt with later from the bank or by canoe. This included one new patch found in a ditch near Fen Causeway that we weren’t previously aware of (now dealt with from the bank)

We then finished with some refreshments… Pennywort drink from Cho Mee supermarket was interesting to try (and is apparently good for arthritis) but more conventional drinks were more popular!

The days’ work will be immensely useful in the eradication process, although I’m sure we’ll all need to remain vigilant to collect regrowth during the summer

Do keep an eye out when you’re on or by the river over the summer, and either remove any that you see, or just let us know and we’ll try to get someone out to deal with it. If you want to keep an eye on progress before you go pennywort hunting , do check the status reports on our website here: 

If you would like to be kept informed of future working parties, do let us know, ideally registering here

Himalayan Balsam

Himalayan Balsam is a pretty, but very invasive plant along our riverbanks.  It crowds out everything else, fires its seeds everywhere so they float down the river to colonise new areas. When it dies back in winter the bare soil washes away, increasing erosion and flood risk.

After a meeting to discuss how to deal with it, we were shocked to discover some specimens being carefully tended in the flower beds of  the Red Lion Pub in Grantchester!

Secret pennywort pullers

We know there are “secret” pennywort pullers, who quietly help remove it from “their” patch of the river

Here is Ed, who keeps an eye out for it between Sheeps Green Cambridge, and Fen Ditton.  Do say Hi if you see him.

First Pennywort Hitsquad

Simon takes a large punt up river under dramatic skies, ready for the start of the first Pennywort Hitsquad.

These are follow-on sessions from the Treeworks, with our contractors ML Partnership spending 2 days working their way down the river in a giant punt on loan from Scudamores. Their tasks are pulling out some of the remaining trees that had rooted in the river, removing pennywort-containing-debris, and pulling pennywort.

We have funding from Cambridge Water’s PEBBLE fund and South Cambs Wildlife Enhancement Scheme to run 3 more of these, as needed during the summer and Autumn.

Very pleasingly, thanks to all the work in February and March, there’s currently no pennywort for them to pull, but we know it will appear soon….



Pennywort Pulling Working Party postponed to 8 July

Cam Valley Forum’s 2018 Pennywort Pulling Working Party has been postponed from May to July, due to a very pleasing lack of pennywort to pull! New date is Sunday 8 July, 1:30pm outside Cambridge Canoe Club, followed by refreshments.  Do come as a group or as an individual.  If you have them, please bring rakes, buckets, punts etc! For details and to book (which helps us plan and gets you a reminder) click here.

AGM Thursday 29 March

All are welcome to the Cam Valley Forum AGM at 7pm on Thursday 29th March in the David Attenborough Building, New Museum Site, Pembroke Street, Cambridge. CB2 3QZ

Following the AGM, our speaker at 7:45pm will be Catherine Montcrieff of WWF, on “Are we water wise?”

Details here CVF AGM 2018 Notice


Treeworks completed

With thanks to all our funders, and the hard working team from ML Partnership, we’ve now completed 2.8km of treeworks and pennywort clearance on the upper Cam. The team have cleared all the way from the Grantchester Mill Stream to Lammas Land Car Park in Cambridge.

It should be a great help in our battle to eradicate Floating Pennywort from the upper Cam within 5 years