Snapanabhishekam is an auspicious ritual held to Kanakadurga Ammavaru in Vijayawada Temple of Indrakeeladri. It is held thrice in a year. Ugadi (Chaitra Shuddha Padyami), Shravana Masam Pavitrotsavams and first day of Sharan Navaratri utsavams are the three prime occasions for Snapanabhishekam.
Pradhanamurthi in Garabhagriha is offered Snapanabhisheka with panchamritas and pavitra Krishna river waters amidst the chanting of Veda Mantras by pundits. This is a common ritual but Agamashastra tells that apart from the above three instances, there will be some more occasions where Snapanabhishekam could be done to Kanakadurga Ammavaru.
The other Snapanabhishekam instances are..
If utsava vigrahas (processional deities) drenched in rain.
Anyone died in temple primises.
After Surya Grahan and Chandra Grahan (Solar & Lunar Eclipses).
When any kind of repairs done in Garbhalaya.
During the eclipses, the temple is closed. After performing Samprokshana pujas only, the deities are cleansed and the temple reopened.