Winterbourne streams on our chalk soil traditionally run after seasonal rains have percolated through the chalk (which holds the water underground as an aquifer or sponge). As the water table rises, the water starts to flow steadily through fissures in the chalk which we know as springs.
In East Garston we are about five miles from the source of the River Lambourn in Upper Lambourn. Along this part of the Lambourn Valley the stream usually dries up completely around July (although some years the stream doesn’t flow at all; some years it doesn’t stop).
This year the river sprung back to life as normal mid-February in just over one week. It was very similar to the rising last year:
From Great Shefford eastwards the river flows continually year round and feeds into the River Kennet just south of the Thatcham Discovery Centre (according to Wikipedia it was in the triangle where the two rivers met that Charles I took up a defensive position in the Second Battle of Newbury 1644).
As the springs start feeding the river bed west of Great Shefford wildlife quickly take advantage of the extended water course. According to local wildlife author Nicola Chester, ducks fly along streams and will quickly spot water starting to flow as the spring head moves upstream. Two pairs landed within hours of the water starting to flow past our house.
It’s only the mammals that are phased by the arrival of the water: our two kittens and a friendly muntjac that visits the garden on the opposite riverbank looked most perplexed this morning.
2 Responses
It’s late! When I lived in Great Shefford just over 30 years ago I had an elderly friend who was born and bred in Lambourn who said the river traditionally dried up in November and started flowing again on January 23-25.
Erica –
Thanks for your comment.
We’ve noticed that it’s normal that it tends to dry up in August and returns in early January but there are variations. Some years it flows all winter and at others it’s dry for 18 months. A book, ‘East Garston Past and Present’, was published in 2000 and on p28 there’s a chart showing the periods of flow from 1964 to 1999. In four of these years in flowed continuously and in four others it didn’t flow at all, including a 27-month dry period from August 1990 to November 1992. In 11 of these years it was flowing in either September or October or both. In five years it started flowing in December or thereabouts but had stopped again by mid-June. I don’t know if there are any figures for the years since 1999. I think that water abstraction has recently made the situation worse but it’s always been quite capricious.
Brian Quinn