Abstraction licence modification secures winter water storage for Norfolk crop irrigation

Heronhill had an existing licence allowing water abstraction between the months of November-April for a licenced quantity of 681,818m3/annum, subject to a Hands-Off Flow (HoF) condition. This did not permit abstraction when the flow of the river fell below a specified level, to protect the ecological system for Brown Trout in the River Nar.

The Environment Agency had closely monitored the River Nar and had invested in improvements to make the river a habitat in which the Brown Trout can thrive. The Environment Agency feared that changes to the river flow caused by abstraction at lower flows, would negatively impact the ecological system of the Brown Trout.

Therefore, Heronhill’s existing licence restrictions prevented the abstraction of the full licensed quantity of water.

Using both historical data obtained by the Environment Agency and incorporating a new scheme of monitoring, Envireau’s hydrogeologists analysed the relationship between river flows, abstraction, and ecological sensitivity against the Hands-Off-Flow condition to establish where genuine headroom existed for additional abstraction without affecting the Brown Trout population. Based on the data collected, we built a well-documented technical case demonstrating that the proposed modification would not adversely affect the river’s ecology. This evidence-based approach meant the case could be submitted to the Environment Agency with confidence, providing the assurance needed to agree the change.

Within four months, Envireau secured a modification to Heronhill’s abstraction licence, enabling them to abstract their full licensed quantity of 681,818m³/annum. Heronhill can now reliably store enough water each winter to irrigate its crops throughout the following growing season, without risk of supply shortfalls.