A recent look at a map of Britain’s chalk rivers gave me a surprise. Without realising it I have, it seems, lived several years of my life near waterways that rise from the chalk bedrock of south-east England. Some of my earliest memories are of my grandparents’ bungalow on the banks of the Colne near London. I remember, just, being drawn to the peace of the riverbank and watching long strands of green weed moving gently in the current. 

As a student, I lived a few metres from the Stour in Kent and walked miles along its banks seeking kingfishers, yellow water lilies, and brief glimpses of brown trout rising lazily to the surface. Before moving to Norfolk two decades ago, I lived in a nearly derelict water mill in Hampshire, the disused part of which spanned the wide river Test. In autumn, people used to stand by our front door watching the spectacle of salmon leaping upstream. The silver fish, some as long as my arm, often had to try several times to make it through the old millrace, their tails and muscular backs emerging briefly from the water to gasps from their audience. In early summer, I could sit in the back garden watching mayflies dip and rise above the white flowers of water crowfoot, whilst a family of water voles crouched in a line with their on the bank. Later on, I moved a few miles to a house on a lane that forded the Meon - a smaller and quieter river than the mighty Test. One midnight a friend and I were watching badgers in the old water meadows behind the house, when we heard the clear and unmistakeable whistle of an otter. We knew that the species had been declared extinct in the county a few years before, but here they were, whistling their return through the dark. 

Now I find myself living not far from the Tas, which runs northwards through the South Norfolk Claylands towards Norwich. Like the Meon, it is a river of winter fords, shaded shallows under alder trees and still, quiet pools. I am grateful to the Tas for my best sighting yet of an otter; I was swimming in a deep pool one sunlit afternoon, when a shape in the water caught my attention. Seconds later, the broad head of a dog otter peered at me from just a few feet away, his dark eyes looking curiously at me. I held my breath, looking back before he vanished into the water.  

Only around two hundred chalk rivers are known globally, eighty-five percent of which are found in southern and eastern England. Here in Norfolk, they include not just the Tas, but the Wensum, which flows alongside NWT’s Sweetbriar Marshes nature reserve in Norwich, as well as the Bure, the Tud, the Nar and the Glaven to name a few. All of these watercourses emerge from the chalk with pure water that is rich in minerals and remains at a fairly constant temperature year-round - conditions that encourage a wide range of aquatic plants, invertebrates and fish species. Above the waters, bats and birds feed on insect life and the waterways also create a network of vital corridors for wildlife across the county. 

The sheer number of chalk rivers in Norfolk means that we have recently supported a campaign initiated by Hampshire and Isle of Wight Wildlife Trust, seeking greater recognition and protection for the rivers. Although the clear waters support so much wildlife, they are sadly vulnerable to human impacts. Many have been over-deepened by dredging, or straightened out and cut off from their natural flood plains, whilst the movement of species like eels has been obstructed by sluices or weirs, and pollution from many different sources remains a threat.  

At the end of 2024, Norfolk Wildlife Trust signed a joint letter to parliament advocating for policy changes to protect chalk rivers. The recommendations made included introducing ‘no development’ buffer zones around chalk streams, considering the implications of sewerage systems in local plans and, crucially, designating chalk rivers and their catchments as irreplaceable habitats. Irreplaceable habitats are those like ancient woodlands, which are difficult or impossible to re-create and that consequently need special protection, especially when new houses or infrastructure such as roads are planned. At the time of writing, our wonderful chalk rivers do not have this protection. 

Norfolk Wildlife Trust will continue to advocate for these irreplaceable waterways, to help give our chalk streams, and the wildlife they nurture, a fighting chance. We will also speak out against developments that could do our chalk streams harm, such as in the case of the Norwich Western Link road. 

As we continue with our efforts, we’ll be sure to let you know when you can add your voice to ours. And in the meantime, there is one thing we can all do, whether we swim, bird watch, fish or just enjoy walking along riverbanks. It is simply this - take a moment to see what you can spot living in the river and don’t let these lovely places go unnoticed any longer. 

Save our Chalk Streams