The HS2 construction programme dictates the duration of the licence variation however, as the final programme has yet to be confirmed, Affinity Water has suggested a 6-year variation period from 31 March 2020 to 31 March 2025 to “cover all possibilities”.
The extension outlines the period that Affinity Water may abstract 32,120,000 cubic metres per. After 31 March 2025, the annual abstraction rate will be reduced to 29,200,00 cubic metres per year.
The abstraction limit applies to the combined activity at Batchworth, West Hyde, Blackford and six other sites which are not affected by the proposal.
The variation specifies increases in peak daily abstraction rates:
- Batchworth: Increased peak daily abstraction rate from 20,457 cubic metres per day to 28,000 cubic metres per day (30 month duration)
- West Hyde: increased peak daily abstraction rate from 20,457 cubic metres per day to 22,457 metres per day (30 month duration)
The licensed annual volume of water will not increase as a result of these changes.
Affinity Water proposes to increase peak daily abstraction rates from these sites only in the event that the Blackford site (abstraction rate 20,000 cubic metres per day) and/or other sites are:
- Affected by turbidity from HS2 construction
- Experiencing full of partial outage
The new peak daily abstraction rates were calculated from an assessment of the impacts HS2 construction is likely to have upon Affinity Water’s supply capability.
According to the Environment Agency, the proposal is not intended to enable Affinity Water to supply HS2 with water for construction. Instead, the variation will help Affinity Water maintain resilience of supply during times of peak demand. All water abstracted will be for the purpose of public water supply.
To help mitigate the impact of the HS2 programme, Thames Water has agreed to contribute up to 10 Ml/d to be used as required. However, the consultation documents state that 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”.
In the application, Affinity Water claim that to maintain supply resilience it is essential to increase the peak licences above 10 Ml/d:
“this in conjunction with the maximum 10 Ml/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”