A PLAN by Wessex Water to build a washout facility that will discharge dirty water into a prime stretch of the River Avon just outside Salisbury, has been slammed by Salisbury Angling Club as “irresponsible.”

The water authority wants to discharge up to 139 litres of water a second for 20 minutes at a time, six times a day into a sidestream just 60 metres from the main Avon near Stratford Bridge between Durnford and Stratford-sub-Castle.

The stretch of the River Avon through Durnford and the Woodford Valley is the flagship trout fishery for Salisbury Angling Club, visited by hundreds of anglers each year and is renowned for its high levels of invertebrates, plant life, fish life and for a colony of water voles, a protected species.

Andreas Topintzis, general manager of Salisbury Angling Club said: “Wessex Water want to go to a flagship fishery in a renowned river and dump their run-off.

“This area is a valuable environmental and angling asset.

“The carriers and streams around the main river provide nursery and shelter for migratory fish and the fragile, small-scale systems, are easily damaged.”

He said the surplus water, which is to be pumped from the washout, would contain not only particles of chalk and sediment, but more dangerously, nitrates and phosphates, which would do serious harm to the delicate river system. The water quality of the river is monitored monthly at 10 sites by the club.

He said in view of the status of the River Avon and the entire Avon Valley – it has European status as a Special Area of Conservation (SAC) – the proposed actions by the water authority were nothing short of “irresponsible.”

Aquatic invertebrates that have been there for hundreds of years and are highly sensitive to increased levels of siltation could be lost forever.

The water authority said it requires the construction of a washout facility associated with the boreholes at the Deans Farm Water Treatment Works to take the discharge from the “first flush of higher turbidity water” when the pumps start up.

After discharging the required amount, the pumps would divert the water into the main supply network.

The discharge point would be positioned on a side channel close to the main river which will allow the flow to dissipate into the main river.

The authority said its proposal has been approved by the Environment Agency and Natural England.

The angling club objected last year when it discovered the authority wanted to build the washout facility as part of its huge project to construct a new supply grid from Corfe Mullen to Salisbury enabling it to transfer water from Dorset to south Wiltshire.

The project, involving 124 miles of pipeline, is due to be completed in 2017.

The angling club has reiterated its objection to the washout plan and together with Wiltshire Wildlife Trust’s Chalkstream Project and the Durnford Estate, has come up with an alternative solution involving settlement ponds, which would allow the sediment, nitrates and phosphates to settle before what would then be clean water, would discharge into the river.

The club is now seeking the support of the national Salmon and Trout Conservation group, Angling Trust and Fish Legal as well as landowners and 2,000-plus membership.