Tyndrum Wastewater Treatment Works (WwTW) in Stirlingshire, Scotland, has completed a major upgrade that more than triples its process screening capacity. The project increases the site’s ability to manage incoming flows from 3.2 litres per second (L/s) to up to 10.6 L/s. Following a successful reliability period, the upgraded plant has now been handed over to Scottish Water.
Screening is a vital early stage of wastewater treatment, removing large solids that can cause blockages or damage downstream equipment. Ensuring assets are appropriately sized and well maintained is essential for protecting operational performance.
The age of the plant, originally constructed in 1981, and its location within a small village heavily visited during the summer months posed challenges during the upgrade. WGM Engineering delivered the full design along with civils, construction, mechanical, electrical, instrumentation, control and automation (MEICA) works and commissioning.
Maintaining Operations During Construction
Throughout construction, Tyndrum WwTW had to remain fully operational in order to continue serving the local community. Temporary screenings and over-ground pumping were installed to maintain service continuity. During excavation, the team uncovered several uncharted legacy services located in critical areas of the planned works, requiring design revisions and careful management.
WGM Engineering Project Manager Scott Ross said: “The screening upgrade work at Tyndrum has been a very rewarding but challenging project to be involved with. This was due to the environment and time constraints that the project was delivered in. Throughout the work, the plant had to remain functional to continue serving the village, so temporary screenings and over-ground pumping were installed for the duration.”
Upgraded filtration infrastructure at Tyndrum treatment works.
The presence of unknown buried services meant traditional mechanical digging methods could not be used safely. To mitigate risks, the team deployed vacuum excavation techniques in line with Scottish Water’s ‘zero strike’ policy, greatly reducing the likelihood of damaging cables or pipelines.
Retrofit Approach Reduces Carbon and Extends Asset Life
The project followed a retrofit strategy that retained and enhanced existing infrastructure rather than constructing a new plant. This approach delivered operational benefits while reducing cost and environmental impact. Construction materials were reused locally where possible, including for hardstanding areas, parking and boundary improvements. The team estimates a carbon saving of 10–11 tonnes CO₂ equivalent as a result of this approach.
Upgrades to the MEICA systems included modifications to the original electrical control panel, which did not have sufficient capacity for the new screening equipment. An enhanced panel was installed to accommodate the additional infrastructure.
Scottish Water Project Manager Robin Johnson said: “At Tyndrum WwTW, our collaboration with WGM Engineering delivered an efficient, low-carbon retrofit that kept the works online while more than doubling screening capacity. By working together to navigate legacy services and a tight seasonal window, we strengthened resilience, improved compliance with environmental consents and minimised disruption for customers, the local community and stakeholders.”
