Affinity Water has applied to the Environment Agency to vary an existing abstraction licence to mitigate the potential impacts of High Speed Two Ltd (HS2) construction activities during the construction of its Colne Valley Viaduct.

During part of the construction phase, groundwater abstraction operations at Affinity Water’s BLAF pumping station will cease.

The water company has applied to vary its existing licence which authorises the abstraction of groundwater from three sites near Batchworth, West Hyde and Blackford. The duration of the variation is dictated by the HS2 programme. However, the final construction programme has still to be confirmed so Affinity has suggested a six year period up to 31/03/2025 “to cover all possibilities.”

Affinity Water is seeking an extension to the period that they may abstract 32,120,000 cubic metres per year from 31 March 2020 to 31 March 2025. Thereafter, the annual abstraction rate will reduce to 29,200,000 cubic metres per year. The limit applies to the combined abstraction at the three sites and six other sites which are not affected by thE proposal. The variation includes:

• An increase in the peak daily abstraction rate at the Batchworth site from 20,457 cubic metre per day to 28,000 cubic metres per day, effective for 30 months. The licensed annual volume of water will not increase as a result of this.
• An increase in the peak daily abstraction rate at the West Hyde site from 20,457 cubic metres per day to 22,457 cubic metres per day, effective for 30 months. The licensed annual volume of water will not increase as a result of this.

The increase in peak daily abstraction rates is only intended to commence in the event that the Blackford site, which allows abstraction at a rate of 20,000 cubic metres per day, and/or other sites are affected by turbidity arising from construction of HS2 and are experiencing full or partial outage.

The new peak values were determined by assessing the impacts HS2 is likely to incur upon Affinity Water’s supply capability.

All water abstracted is for the purpose of public water supply and the variation will contribute to maintaining resilience of supply during episodes of peak demand. The Environment Agency said the proposal is not intended to enable Affinity Water Limited to supply HS2 with water for construction activities.

As part of the solution up to 10Ml/d is also being sought from Thames Water as an important source to be used as required. However, according to the consultation documents there is still “a large amount of uncertainty surrounding the imported water, whether it will be available at all times or whether it will be subject to restrictions.”

The application says it is critical for Affinity Water’s resilence that the peak licences are increased to above 10Ml/d, commenting:

“this in conjunction with the maximum 10Ml/d import would only cover the best case scenario, leaving a high residual risk to Affinity Water and its customers as a direct result of HS2.”

Deadline to comment on the application is 31^st January 2020 – click here to access and comment on the application online.