Client: Scottish Water
Sector: Water
Project value: £2.8M
Location: Dunoon, Argyll & Bute
Mackenzie Construction refurbished Dunoon DSR Reservoirs 1–4 under Scottish Water’s Simple Repairs Framework. Located in a remote, environmentally sensitive area, the tanks had not been taken offline for over a decade. Initially thought to operate as a single unit, our investigative work revealed interdependent tanks with buried chambers and isolating valves. Works included structural remediation, civil engineering, environmental upgrades and access improvements, extending the reservoirs’ life by at least 20 years.
The remote location created logistical hurdles: ferry-dependent deliveries, materials manually carried up a 150m incline and limited access for machinery. Weather and winter conditions also brought challenges along with environmental sensitivities including Japanese knotweed containment and wildlife protection.
A bypass system maintained water supply while tanks were offline. The team carried out flood testing, waterproofing, edge remediation, pipework upgrades and access improvements. Close collaboration with Scottish Water’s ecology team ensured flora and fauna were protected. Community engagement included supporting local businesses and charitable donations, strengthening Mackenzie Construction’s presence beyond the site.
Low-Carbon Concrete: Structural repairs using environmentally friendly concrete, maintaining strength while reducing carbon.
Proofex Waterproofing Membrane: Long-lasting, low-carbon solution for damp conditions.
Smart Surface Technology: Consolidated existing road materials, improving access and reducing carbon footprint.
Battery-Powered Lighting: Reduced emissions and noise, especially during winter months.
The reservoirs now meet modern water quality and operational standards. The insights uncovered around the design of the system now means that Scottish Water can manage tanks flexibly, reducing the need for full system outages. The site is safer, more accessible and visually improved. The project also offered extensive staff development opportunities, embedding cross-disciplinary learning and upskilling on innovative techniques.
This project exemplifies Mackenzie Construction’s ability to deliver complex, multi-disciplinary infrastructure works in challenging environments, combining innovation, sustainability and operational excellence to create lasting value.