The Persian goddess of water and fertility is Anahita.
Anahita is the Old Persian form of an Iranian goddess whose Avestan name is Arədvī Sūrā Anāhitā. She is primarily associated with the Waters and with the life-giving powers of rivers, springs, rain, and irrigation. Because water sustains crops, animals, and human life, her sphere also includes fertility, healing, and wisdom.
Her worship appears in Zoroastrian religious tradition, especially in the Aban Yasht of the Avesta, where she is praised as a powerful and pure divinity. Ancient Iranian tradition also treated her as a cosmic river or source of the waters flowing across the earth. Later Persian and neighboring traditions used forms such as Anāhitā, Anāhid, and Anahit.
Anahita should not be confused with Ahura Mazda, the supreme wise lord in Zoroastrianism, or Mithra, a major divinity associated with covenants and light. Hvare-khshaeta is linked to the sun, not primarily to water and fertility.