NAIROBI, Kenya, Apr 6-Residents in Nairobi and neighboring counties are set to experience a five-day water supply interruption beginning Tuesday, as the Athi Water Works Development Agency undertakes critical infrastructure upgrades on the Northern Collector Tunnel (NCT) Bulk Water System.In a public notice, the agency said the planned shutdown will start at 8:00 a.m. on Tuesday, April 7, 2026, and continue until 8:00 a.m. on Sunday, April 12, 2026.The interruption is intended to facilitate installation and strengthening works on the Raw Water Gravity Transmission Pipeline running from Ndakaini Dam to the Kigoro Water Treatment Plant, as well as improvements to treated water transmission pipelines extending to the Gigiri Reservoir.The agency explained that the works are part of ongoing efforts to optimize operations and enhance the resilience of the region’s bulk water supply network.“The shutdown will affect all consumers dependent on the NCT Bulk Water System, including those served by Gatanga Water & Sanitation Company, Nairobi City Water and Sewerage Company, Oloolaiser Water & Sewerage Company, EPZA, and Mavoko Water & Sewerage Company,” the Agency said.Residents, businesses, and institutions within the affected supply zones have been advised to store adequate water in advance and to use available supplies sparingly throughout the interruption period.“AWWDA appeals for patience and cooperation from all affected consumers as it undertakes these necessary works aimed at improving the resilience and overall performance of the regional water supply network,” the agency said.The Northern Collector Tunnel Bulk Water System currently supplies approximately 140 million litres of clean water daily to communities across Nairobi, Kiambu, Murang’a, Kajiado, and Machakos counties, making it a critical component of the region’s water infrastructure.