water meadow

noun3

1. •
   An area of grassland, besides a river, that is subject to periodic flooding.
2. •
   A low-lying area of grassland, such as that by a river, which is subject to seasonal flooding.

   • He was too vivid a mark, as he dazzled slowly across the green water-meadows. — 1967
3. •
   An area of grassland subject to controlled irrigation or flooding in order to increase agricultural productivity.