Blog & News

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

Extra funding for treeworks

The Environment Agency visited last week, and were so impressed they’ve awarded us/The Wildlife Trust extra funding to allow work to continue downstream, hopefully all the way to Mill Lane, Cambridge.

MLP have developed a slick working method and are making good progress. In the picture above they are working from right (upstream) to left (downstream). The workers are just visible behind the punts, loading them up with brush and pennywort.  The punts are then pulled across the river using a fixed rope to be unloaded on the opposite bank. The debris is left in piles for the farmer to remove or chip. The light green patch on the left of this picture is Floating Pennywort.

We are deliberately leaving a few “habitat refuges” for birds and fish. With the help of the Cambridge Canoe club we are installing protective barriers, which will hopefully stop them becoming completely clogged with Pennywort….. But we’ll find out later in the year whether this works.

Treeworks start on schedule

Despite floods, cold weather warnings and even a few flurries of snow, our contractors ML Partnership start the massive task of pruning back the overhanging trees that have been causing such trouble trapping pennywort on the upper Cam.

It’s going to be a big job!

Wet weather has made the access track on the east bank impassible, so they’re working from 2 large punts on loan from Scudamores.

These were brought up river by two Cam Valley Forum volunteers, Simon and Alec, a few days before


Chicane boom installed on upper Cam

In preparation for the treeworks, Cam Valley Forum and Cambridge Canoe Club have installed Cam Conservators’ chicane boom system. This is in the same position as Cam Conservators installed it last year, between the River Bank club and Grantchester Meadows.

These booms are designed to catch Floating Pennywort that is released during the treeworks. Ideally the debris will all be channelled to the West bank where it can easily be removed from the bank with rakes, or by the canoe club from the water.  We hope to keep it in place as long as possible, but if it starts to cause a problem when river traffic increases after Easter, please let us know and we will remove it.

We need volunteers to join us in helping keep it (and the rest of the upper Cam) clear of Floating Pennywort, so if you would like to help, do register here.

Given the link between Floating Pennywort infestation and climate change (warming increases the growing season), we are quietly pleased how much of the job was human-powered.

The booms were taken to the river bank by specially adapted bike trailer…

Then towed up the river….

and installed.


Treeworks project now fully funded

Clearing a path through the Floating Pennywort, Grantchester Meadows, Nov 2017

Thanks to a grant from Cambridge Water’s PEBBLE fund, recent match funding from the Environment Agency and support from a variety of other organisations, we will be engaging the contractors ML Partnership to prune back about 1km of the willows that are drooping into the Cam as it flows past Grantchester Meadows. These trap the Floating Pennywort and make it impossible to clear.

The tree works should make the upper Cam much less likely to become totally clogged with Pennywort in 2018. It will also help in our aim of  eradicating it from the upper Cam within 5 years.

The work will start on 5 Feb and last several weeks (depending on the weather).  Because of the very wet conditions, it will have to be done from the Grantchester Meadows side, so we apologise in advance for the temporary mess and any inconvenience.

River users please be aware that there will be a chicane catchment boom installed just upstream of the Riverbank Club until Easter in order to help catch the released Pennywort and other debris. This will be clearly marked.

This project is supported by many volunteers and:

Cam Conservators (funding and loan of catchment booms)
Cambridge Canoe Club (help installing and clearing catchment booms)
Cam Valley Forum (management and funding)
The Environment Agency (funding and mechanical clearance)
Grantchester Trust (funding)
The Riverbank Club (temporary storage of booms)
Scudamores (funding and punts)
Trumpington Farm Company (funding and debris clearance)
The Wildlife Trust BCN (management and advice)

Cam Valley Forum afloat

Thanks to a generous donation from one of our supporters, Cam Valley Forum now has an inflatable dingy.  Even better, it can be rolled up and transported in a bike trailer!

When the water warms up a bit, we’ll be using this to help with pennywort pulling working parties on Grantchester Meadows.