At the point chosen for all the experiments, the river is a slow-flowing drainage canal running in an uninterrupted straight line for a six-mile (9.7 km) stretch to the north-east of the village of Welney.
Sungai yang dipilih untuk semua percobaan adalah kanal drainase berarus lambat membentang lurus tanpa hambatan sepanjang 6-mil (9,7 km)* ke timur laut desa Welney.