low water

plural low waters

1. countableuncountableThe location of low tide in a coastal area.

   The railway then follows the widening estuary of the river, which at high tide has the appearance of a lake, but at low water presents a rather cheerless expanse of dark mud.

   1953 February, H. A. Vallance, “To Brighton through the Shoreham Gap”, in Railway Magazine, page 82

   Synonyms: LW

2. countableuncountableThe lowest stage of a river.
3. countableuncountableThe temporary situation of having little money.

   Miss Monro’s eyes glistened. It struck me that she was in exceedingly low water, and that the chance of a square meal was not to be despised.

   1927, Agatha Christie, The Big Four