What live sewage spill data does (and doesn’t) tell us about water pollution

Maximillian cabinet/Shutterstock During periods of heavy rainfall, pipes known as storm overflows aim to prevent excess water overflowing into the sewage system. But this is not always the case. During intense rainfall, combined sewers (which carry both wastewater from homes and businesses and rainwater running off roads and buildings into drains) can exceed their capacity. To reduce the risk of sewage flooding homes, businesses and roads, storm overflow pipes can contain excess water. Then…