JN Bentley - Allendale Sewage Treatment Works

Challenge

Allendale Sewage Treatment Works required a reliable temporary power solution while awaiting a permanent mains power connection. The site had previously been supplied with unsuitable generators, resulting in multiple power failures in a short period of time. Due to strict environmental controls, any loss of power carried the risk of fines of up to £250,000 per incident if sewage were to overflow into the nearby River Allen.

Following these failures, confidence in the existing supplier and equipment was significantly reduced. JN Bentley were instructed to urgently change supplier and eliminate the risk of further outages. Compounding the challenge, the site operates with only a four-hour contingency window during a power failure, and its remote location, three hours from the depot, made rapid response and equipment replacement particularly critical, especially over the Christmas period.

Solution

We took over full responsibility for powering the site, designing a resilient and fail-safe temporary power setup tailored to the site’s critical nature. The solution comprised:

Two 200kVA generators configured in an AMF (Automatic Mains Failure) setup, with one acting as the main runner and the second as an immediate backup.

A third 200kVA generator positioned on site as a contingency unit, ensuring zero downtime in the event of a catastrophic failure requiring generator replacement.

Bespoke on-call engineering support, including additional engineers dedicated specifically to this site to overcome the standard four-hour response limitation.

On-site fuel transfer, utilising fuel from the failed generators to minimise disruption and speed up stabilisation.

To provide complete reassurance, senior team members attended site alongside Northumbrian Water representatives and our engineers to carry out live mains failure testing, confirming the AMF system operated exactly as required.

Result

The upgraded power solution restored confidence for both JN Bentley and their end client, eliminating the risk of further power failures and preventing costly environmental fines. The site now benefits from a robust, multi-layered backup system, enhanced engineering support, and proven performance under live test conditions.

By delivering a resilient and responsive temporary power setup, we ensured uninterrupted operation of a critical sewage treatment facility and provided the peace of mind required for a high-risk, high-penalty site.