Roger Wilding, Wycombe Wildlife Group reports :
Whilst the recent very severe flooding in parts of the country was headline news, our local area has not escaped the effects of the wettest winter on record. Exceptional amounts of water in the Thames caused flooding in Marlow resulting in the Thames Path, Higginson Park and some properties being flooded, and Wycombe Wildlife Group’s planned bird walk around Spade Oak Lake Nature Reserve having to be cancelled. The wet winter also topped up the chalk aquifers in the Chilterns, and for the second year running the winterbourne stretches of our local chalk streams have risen from sources much further upstream than usual: this year the streams have been flowing over longer distances, and with a stronger flow, than in 2013.
In early 2013, the Wye was flowing from near Inver Farm along Bottom Road between West Wycombe and Radnage, whereas in March 2014, the stream was flowing along Grange Farm Road, west of Bennett End. The Hughenden Stream, which had a continuous flow from Warrendene Road in the Hughenden valley just south of the crossroads near Lower Warren Farm, produced more water than the underground pipes through the residential areas could cope with, resulting in a mix of pure spring water and sewerage which had to be pumped into the Hughenden Stream as a temporary solution.
Perhaps the most interesting result of the high flows has been the appearance of a new tributary of the Wye, which, in the absence of any other name I will refer to as the Saunderton Stream, has had a continuous flow all the way from near Saunderton Station to West Wycombe, causing a flood, requiring the use of sandbags and the installation of pumping equipment at Saunderton, and a flood across the A40 near the Pedestal at West Wycombe.
Wycombe District’s other chalk stream, the Hambledon Brook (or Hamble), which flows into the Thames at Mill End near Hambledon Lock, was flowing from the Turville end of Watery Lane in early 2013, but this year it has been flowing along the road through Turville, having risen from springs in the roadside woods west of the village.
Although we feel very sorry for those people whose properties have been affected by flooding, the local chalk stream flooding is a natural occurrence, and a sign that our local chalk streams are acting as they should following a very wet season. A fast winter flow improves the quality of a chalk stream by removing silt from the riverbed gravels, benefiting both the fauna and flora. These occasional happenings also act as a reminder that the flood plain of our chalk streams covers the whole winterbourne section of each stream, even where it may remain dry for ten years or more at a time.