The issue

Scottish Water, which supports 2.57 million households and close to 153,000 businesses in Scotland, was facing problems with flooding and spills, especially Combined Sewer Overflows (CSOs), in the city of Perth. Managing over 33,000 miles of sewer pipes and treating over 1 billion of litres of wastewater daily, the water utility was looking for creative and efficient ways to resolve these issues while considering future growths that included reduced carbon impact to meet sustainability goals. Constructability concerns, such as challenges along historic bridge embankments, added complexity to the problem.

The solution

To tackle these challenges, Scottish Water turned to SUEZ, which employed Optimizer™ for ICM, a tool that helps identify cost-effective, alternative upgrades within Perth's combined sewer network. Optimizer is a cloud-based optimization software solution that comprehensively analyses water distribution and collection systems. It assesses various asset categories, including pipes, pumps, storages, and control facilities, along with different size combinations, considering multiple criteria such as cost, hydraulic performance, energy, and water quality.

The optimisation process used for Scottish Water explored options like increasing pipe size, changing alignments, adding offline and in-line storage, surface water removal, and altering how water is managed. Using a unique, three-objective optimisation, the SUEZ solution considered cost, performance, and carbon impact, which fully aligned with Scottish Water's goal of achieving net-zero emissions.

The result

Scottish Water developed a protocol for using Optimizer to identify optimal strategies for the "Options Development and Appraisal Stage" of their Drainage and Wastewater Management Plan in Perth. By running various scenarios, Scottish Water found optimal strategies that factored in carbon impact alongside cost and performance. This helped the utility understand what changes and investments were needed to handle future challenges.

Optimizer not only expedited the identification of optimal pipe upsizing solutions but also provided a much quicker analysis time compared to traditional manual approaches. This collaborative approach led to effective problem-solving and streamlined the network's whole process.