A vocabulary of landscape — a landscape of words 1054 entries

water-meadow

WAW-ter MED-oh
A water-meadow is a river meadow deliberately flooded in a controlled way by a system of channels, hatches, and ridges, so that a thin sheet of moving water runs over the grass in late winter. The water is a few degrees warmer than the air and it keeps frost off, so grass starts growing weeks early and provides the first bite when the winter fodder has run out. It is engineering, not accident.
Etymology
The English term distinguishes it from an ordinary flood meadow, which floods when the river does and is not managed. The technique is called floating a meadow, and the person who ran the system was a drowner.
Notes
The system transformed sheep farming in southern England from the seventeenth century, because the early bite let a flock be kept through the hungry gap and folded on the arable at night, which manured the corn. The channel networks are still visible as low corrugations in valley meadows in Wiltshire, Hampshire, and Dorset, and a few systems have been brought back into working order.