Mammy Water: In Search of the Water Spirits in Nigeria 1983 on netflix

Mammy Water is a pidgin English name for a local water goddess worshipped by the Ibibio, Ijaw, and Igbo speaking peoples of southeastern Nigeria. The water goddess traditionally gives wealth and children, compensates for hardships, and is sought in times of illness and need, especially by women. Her various cults are led, predominantly, by priestesses.