Si Collection, Upper Volume
Radical: Water (shuǐ)
Entry: 汬
Kangxi Strokes: 8
Page 607, Entry 14
According to the Jade Chapters (Yupian), this is an ancient form of the character for pit or trap (jǐng). For a detailed explanation, see the entry in the Mound (fù) radical, under the four-stroke section.