Birpur, in the far north-east of Supaul district, sits beside one of the great engineering works of the region: the Kosi Barrage at nearby Bhimnagar, built in 1963 on the India–Nepal border to control the Kosi — the river so prone to catastrophic floods and course-changes that it is called the “Sorrow of Bihar.” The barrage, its embankments and the Kosi project headquarters made Birpur a planned town in a land of villages.
It is a place where Mithila’s oldest adversary — the wandering, untamable Kosi — meets its most modern attempt at an answer, and where the floods of 2008, when the river breached its embankment upstream, are still keenly remembered.