Repairs underway at Northenden Weir following storm damage

Following a series of intense storms throughout 2023 and 2024 that raised river levels, the masonry blocks of the weir sustained damage, prompting this proactive maintenance initiative.

The weir plays a vital role in providing Flood Warnings and Alerts to communities along the River Mersey, including Northenden and Didsbury, by offering a consistent water level reading via the Northenden River Level Gauge. It is essential for maintaining the stability of river embankments and walls, which serve as critical flood defences for local residents.

The Environment Agency has been closely monitoring the weir's condition in the aftermath of the storm events and recently noted further deterioration. In response, it is undertaking repairs before the onset of winter, which could exacerbate the existing damage.

The inspection began on 18 November when a section of the weir was dewatered to facilitate a comprehensive assessment of the structure's condition. To achieve this, the Environment Agency employed a helicopter to deploy 100 one-tonne bulk rock bags upstream, redirecting water away from the weir and exposing it for inspection. This method was deemed the most efficient and cost-effective, allowing for rapid installation to prevent further degradation.

The deterioration of the weir presents a potential risk to recreational river users, such as canoeists, as damage is not readily visible from upstream. The Environment Agency has taken precautionary measures by erecting additional signage to warn users of the associated dangers and advises the public to avoid the area until repairs are completed.

Once the condition of the weir has been fully evaluated, repair works will follow promptly, with the EA aiming to complete the project by early in the New Year. The proactive maintenance of Northenden Weir underscores the importance of safeguarding local communities from flooding, particularly in light of the increasing frequency of severe weather events.

Environment Agency operations and duty incident manager Jamie Dixon said: “We’ve been monitoring Northenden Weir for months, and unfortunately, it has deteriorated to the point where we couldn’t risk leaving it over winter. We are therefore enacting a robust repair plan and taking decisive action to protect homes, businesses and infrastructure upstream. The work carried out by VolkerStevin was successful and we’re now in position to carry out the next phase of repair works.”

VolkerStevin project manager Gary Atkinson said: “Northenden Weir plays a critical part in managing flood risk in this area. By maintaining the upstream water level, the weir ensures the river embankments and walls remain stable enabling these flood defences to continue to protect the local communities.

“It is also an integral asset providing foundation support to significant infrastructure upstream including the Didsbury flood storage reservoir. Successfully completing this milestone marks an important step in ensuring the weir can continue to perform its critical role. This achievement is testament to the close collaboration between our team and the Environment Agency, by working together we have delivered this crucial phase safely and efficiently.”

Like what you've read? To receive New Civil Engineer's daily and weekly newsletters click here.