Ceri,
I note that you are a signatory on behalf of NRW on the attached 2018 protocol for the disposal of contaminated water.
I have real concerns on the disposal of wash water from poultry farms due to the impact of the disinfectant on the aquatic environment.
I expressed my concerns at the last Fisheries Forum about the approval of a planning application and construction of a 150,000 bird poultry farm at Fron Bella Farm, Hafod Denbigh, Conwy with approval for a further 75,000 birds (location slides attached). This farm is at 300 m (984 ft) on the head waters of a major spawning tributary of the upper Conwy and is claimed to produce 7.1 Tonne of manure per year. It is unclear from the permit for this farm how wash water will be disposed. Assuming the use of Virkon S applied at the DEFRA dosing rate for poultry farms of 2.8Kg in 750 ltr (0.33 mg/ltr) to cover 2,300 sq m then for the two sheds (each shed is approx 2,000 sq m) it will take 1,500 ltr each time they are cleaned, this occurs 6 time per year producing at least 1,000 ltr of contaminated water for each wash (allowing for evaporation). At this concentration (0.33 mg/ltr) any run-off into the surrounding fields will be lethal to aquatic invertebrates, the data sheet for Virkon S says 0.22 mg/ltr is lethal to aquatic invertebrates and 0.29 mg/ltr is lethal to terrestrial insects. Should the wash water tank be emptied and then sprayed on the surround fields if will find its way into the Afon Nug and then Afon Merddwr both are spawning streams on the upper Conwy, it has taken 15 years to establish this spawning area. In addition it is likely that this water if sprayed on fields will kill all field insects which will impact on field bird populations.
Whilst my concern is for the potential impact from Fron Bella farm on the Conwy I suspect that the same will apply to all poultry farms in river valleys. Can you please advise the policy from NRW/WG with respect to disposal of this contaminated water as it is included within protocol see page 5 item 3 Scope first bullet point.
Regards
Chris White
Conservation officer: Campaign for the Protection of Welsh Fisheries (CPWF)
Leave a Reply