Bourne Eau

Bourne Eau is a short river which rises in the town of Bourne in Lincolnshire, England, and flows in an easterly direction to join the River Glen at Tongue End. It is an embanked river, as its normal level is higher than that of the surrounding Fens. It was navigable in the 18th and 19th century, but now forms an important part of the drainage system that enables the surrounding fen land to be used for agriculture.

Bourne Eau rises in The Wellhead, otherwise known as St Peter's Pool, in Bourne, Lincolnshire. The Wellhead is a natural artesian spring which once formed the source of the water defences of Bourne Castle as well as the power for the town's three mills. On entering Bourne North Fen it follows an artificial course which it was given, probably, in the first half of the thirteenth century when the south Lincolnshire Fens ceased to be a Royal forest. Hitherto, it had occupied the channel known as the Old Ea which was of Roman date, most likely second century. The present course enters the River Glen at Tongue End, a name which derives from the low tongue of land within the enclosing banks of the rivers.

Apart from the spring, most of the water of the river is collected by the Car Dyke, which, near Bourne, is arranged to act as a catchwater drain, gathering the surface water of the upland and feeding it via the Bourne Eau and River Glen to the sea, without its entering The Fens.

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