External sewerage works refer to the comprehensive infrastructure systems designed to manage and transport wastewater from various sources to treatment facilities or discharge points. These works include a network of underground pipes, manholes, and pumping stations that efficiently collect and convey sewage away from homes, buildings, and industrial sites. External sewerage works play a vital role in maintaining public health and environmental sustainability by preventing the contamination of water sources and minimizing the risk of waterborne diseases. These systems employ gravity flow or pumping mechanisms to transport the collected wastewater to treatment plants, where it undergoes processes to remove pollutants and ensure its safe disposal or reuse. With careful planning, construction, and maintenance, external sewerage works contribute to the overall sanitation infrastructure of communities, fostering clean and livable environments for residents and promoting sustainable water management practices.