The River Kennet

Helena C (Re)

The River Kennet is one of England’s most important chalk streams. Measuring about 72km long, it is one of the largest tributaries to the River Thames. In the summer, the Kennet can contribute up to half of the Thames flow. The source starts in Wiltshire’s Silbury Hill and joins the Thames in Reading, Berkshire. The River Kennet is quite a broad river measuring up to 40 to 44ft wide and 5ft deep. This provides the perfect habitat for a varied number of species to live. Throughout history, the Kennet has been used as a source of power for industrial activities using a water mill and in certain places of the river, it has been built to provide a strong flow of water to drive the mills. In the 17th and 18th century, the Kennet water was used to support the brewing and tanning industries in Marlborough and Ramsbury.

In July 2013, a 10 mile stretch of the river, between Hungerford and Marlborough, suffered from chemical contamination. This serious pollution was discovered by volunteers who then made locals aware. The chemicals came from a pesticide called Chlorpyrifos which affected a number of invertebrates but not the fish in the Kennet. The invertebrates play a big role in keeping a balance in the ecosystem therefore needed to be restored. Charlotte Hitchmough, director of Action for the River Kennet, said “usually rivers are left to recover naturally, but this could take years”. She conducted an experiment to help reintroduce invertebrates into the river. She moved invertebrates from healthy areas of the river to damaged areas and measured whether they recovered faster than those who were left to let nature take its course. The results, in August, revealed that the fly count in the river had increased since the pollution which meant that Charlotte Hitchmough’s experiment was a success.

During the autumn of 2022, despite the heavy rainfall in October, the water levels and aquifer levels were below normal for that time of year. The water consumption level in the Kennet was above average despite the current ban on hosepipes. Thames Water also made an application to increase abstraction which was not ideal for the Kennet as it removed essential water for wildlife and changed the rivers natural flow. Due to the low- lying surrounding area, more water is needed to feed the Kennet compared to other rivers. It was predicted at that time, that without significant rainfall through the winter, it was unlikely for the river’s water levels to return back to normal before spring of 2023. On the positive side, we now know that in January 2023, Wiltshire did experience heavy rainfall. However, the drought from before had left the ground hard and baked preventing rain from infiltrating the ground and ultimately led to the river bursting its banks. This wasn’t unpredictable due to the Kennet’s bed rock being chalk and making it more susceptible to groundwater flooding.

With all these disruptions to the natural habitat of the River Kennet, Action for the River Kennet (ARK), aims to create, restore and enhance habitats to keep fish populations healthy through the river. The Kennet is a sanctuary for various plants and animals. The stretch of river between Marlborough and Woolhampton has been named a Site of Specific Scientific Interest and this status allows endangered species to being protected which is why many of those species have migrated to this part of the river.

Different parts of the river house different species of fish; however, some that can be found throughout the river such as bullheads, minnows and brown trout. The Upper Course of the river houses mostly the Salmonidae family, for example brown trout and European grayling. The occasional sighting of the rainbow trout occurs as an escapee and can be recognised by the purple band on its flanks. The Kennet did try to reintroduce the Atlantic salmon back to the river, however found that it didn’t support the necessary conditions needed for the fish to live and they could not follow their migration pattern. In the Middle and Lower Course of the river, near Newbury towards Reading, the fish species start to transition and join the Cyprinidae family. This includes bream, bleak, barbel and many more. Fly fishing in the Kennet is often overlooked, however in this part of the river it offers equally exciting fishing as the more well-known locations. The river offers occasional exciting species and with river management being a high priority, it can only mean that fishermen are getting the best quality of fish possible. Aardvark Mcleod, an international flyfishing specialist, describes the Kennet as “wonderful pristine chalk water providing an abundance of aquatic life.”. He believes that it is one of the most convenient rivers to reach as it is just off the M4 but also provides the best reward for the effort put in. A very common and easy species to spot species is pike. This is because they tend to swim near the surface towards the sun and are found in slow flowing waters and weedy stretches. On the other hand, a rarely spotted species today is the European eel, Anguilla Anguilla. A very common species historically, it is now a critically endangered keystone species. It has one of the longest migrations of thousands of kilometres. Due to its very complicated life cycle, involving both fresh and sea water, its range of threats are increased. It is more likely to face pollution, loss of habitat and hydropower developments than other species.

As seen, the River Kennet is a world of its own, housing dozens of various plants and animals in its chalk river bed. It is a one of England’s most important chalk streams and the largest tributary to the River Thames. The river has faced threats over the years including chemical contamination and droughts, however with organisations like ARK, the Kennet has been able to recover and remain the rare chalk stream that Marlborough takes pride in.