Bypass threat to Binsted Valley

Steve McAuliffe

Guest blogger 

Steve McAuliffe guides us through the special wildlife and rich history of Binsted Valley, which may soon be cut in half if the proposed A27 Arundel Bypass goes ahead. Find out what we stand to lose – and object to the proposals here before the deadline of Tuesday 8 March 2022.

Groundwater filtering through the chalk bedrock of the South Downs collects in deep pools hidden within ancient woodland. Trickles spill over as the aquifers fill following winter rains. Winding through the copper carpet of fallen leaves, the trickles combine on the valley floor. This is the birth of Binsted Rife. A special stream that forms the centrepiece of the Binsted Valley ecosystem.

Above the stream, eight-hundred-year-old coppiced trees encircle the ‘moot mound’. This raised woodland bank is where, throughout the Middle Ages, the ‘Binsted Hundred’ would meet to resolve local disputes.

Twisted veteran trees surrounding the moot mound provide cracks, voids and cavities inhabited by an astonishing assemblage of bats. Fourteen of the eighteen breeding bat species found in the UK have been recorded within five square kilometres of Binsted.

This is a restful corner of West Sussex. There are no through-roads. Skies are dark and nights are quiet. Steep valley sides and saturated wetland soils have resisted the plough. Scattered scrub, tussock grasses and a regiment of dense, upright Phragmites guard its chalk stream artery.

At dusk, caddisflies, moths and midges take to the air in the valley bottom. Myotis alcathoe bats, the UK’s least understood species, commute from the veteran trees of the ancient Binsted Wood Complex to consume the gathering insect feast.

Alcathoe bats are reliant on environments such as this. Old, structurally complex trees providing roost sites in close proximity to steep-sided wetland valleys with insect-rich grassland set within a dark and quiet landscape free of artificial lighting and traffic noise.

This interconnection of features provides a rare and fragile habitat mosaic. Changes to any one of these factors is likely to render the area unsuitable for Alcathoes; along with the Water Voles, Grass Snakes, Hazel Dormice and Barn Owls also found here.

Tightly bound to the fortunes of the valley, the bats and other wildlife within may soon face one such change.

Planned extension of the A27 dual carriageway around Arundel is set to cut the Binsted Valley in half.

Any bats that remain following construction will find themselves facing a largely unsuitable habitat. Vital veteran trees are set to be cleared and the measures proposed to mitigate impacts on bats have been proven ineffective when used elsewhere.

Many of the fourteen bat species recorded in the valley are sensitive to noise and light, and also fly close to ground level. Flying at heights below five meters puts them at risk of vehicle collision. During bat activity surveys along the planned bypass route, over 5,000 records were made of bats flying within the vehicle collision zone.

The decision on whether the bypass goes ahead lies with distant national transport planners. Congregations at the moot mound are no longer able to decide the fate of the Binsted Valley. Local voices have been raised and dismissed. If pleas remain unheard, Binsted bats will no longer course the valley stream and hedgerows. Ancient trees will no longer provide refuge. The moot will have lost its last congregation.

Please object to the bypass today