Forge Dam Update - Apr 2025

We are aiming to keep you updated about the ongoing work at Forge Dam. In our previous blog, we explained how we reached our current position. At that time, we were waiting for various cost estimates before proceeding with some exploratory work.

The exploratory works have been completed, and the findings indicate that infilling the sluice is the most effective solution to prevent water passage. The existing plug is functioning adequately and can remain in place, as it has proven to be sufficient in resisting the applied water pressure.

Sheffield City Council (SCC) submitted a Business Case in February, which included funding to cover the estimated costs for the design.

The Spillway

As previously stated, SCC decided to commence the works in September. This timing allows ample opportunity for an Environment Agency Flood Risk Assessment Permit to be completed and submitted prior to the Easter Weekend, considering the usual 20-week processing period for the permit. Additionally, scheduling the works in September ensures that bird nesting season has concluded and minimises disruption to the café operations, as the lower seating area will need to be closed during the construction period.

Following completion of the exploratory works, a revised design has been developed by Esh/JCC and reviewed by SCC’s Technical Lead and Flood Team. SCC has granted preliminary approval of the designs to enable the submission of the Flood Risk Assessment Permit. Full approval will be granted upon receipt and authorisation of cost estimates.

Since the exploratory works took place, we have seen evidence of water leaking into the embankment. The investigation confirmed that water is passing from the sluice channel through the embankment, and this has become more visible due to disturbance during the works. Importantly, this is not the result of a new leak caused by the exploratory works, and will be resolved with the planned works.

In summary, SCC is currently scheduled to complete the repair work on the sluice in September. As mentioned in our previous blog, we share the concerns regarding water levels during this dry period. However, we are confident at this time that the necessary repairs are progressing as planned and will be completed by early autumn.