The Athlone Main Drainage Scheme is a critical infrastructure project designed to modernize the wastewater treatment and collection systems for Athlone and its surrounding environs. To accommodate a projected ultimate population equivalent (PE) of 100,000—accounting for future development in areas such as Ballykeeran, Glasson, and Coosan—the scheme involves a phased upgrade of the existing treatment plant alongside significant network expansions. A key milestone included the 2016 Design Build and Operate (DBO) contract, which expanded the treatment capacity from 30,000 PE to an interim 40,000 PE.
A major engineering highlight of the project is the complex network upgrade, which involves tunneling under the town centre and multiple crossings of the River Shannon. The works include the construction of 1.4km of 1,200mm diameter tunnel sewers at depths reaching up to 11 meters. These tunnels are essential for integrating the Abbey Road, Coosan, and Canal sections into a unified, high-capacity system. Additionally, the project features a massive 5,000m³ storm water storage tank and a high-capacity pumping station capable of handling 4,600 l/s of storm flow, significantly reducing the risk of flooding and overflows.
Jennings O’Donovan, acting as the lead in a Joint Venture, managed the extensive technical requirements of the scheme. This included organizing detailed sewer network studies, CCTV surveys, and hydraulic modeling to inform the design. The scope also involved significant rehabilitation of 20km of existing sewers to improve structural integrity and reduce infiltration. By managing the project from pre-qualification and tender documentation through to site supervision and the role of PSDP, Jennings O’Donovan has ensured a robust and future-proofed drainage solution for the Shannon region.