Exciting Pushkaram or Pushkar - worship of the holy river - India

Godhavari Maha Pushkaram,2015.godavari maha pushkaram.org
The Hindu religion gives much importance to rivers as most of the rituals and festivals are either directly or indirectly related to water. In Hinduism, the tradition of worshiping rivers has been in vogue for centuries and is going stronger in India despite the advent of  advanced modern technology in many fields.

Pushkaram is an Indian (Hindu) festival dedicated to worshiping of rivers. It is part of the medieval Hindu astrological lore that links the planets and the holy rivers. Also known as Pushkara or Pushkar and Pushkaralu (in Telugu), it is celebrated with devotion and joy at temples or shrines along the banks of 12 major sacred rivers of India. This kind of worship is a sort of dedication to forefathers. It involves certain rituals, cultural programs, spiritual discourses and  devotional music.

Pushkaram  Godavari. aarthi to the river.2015.thenewsminute.com
According to ''Jataka Parijata'', an Indian astrological text written by Vaidyanata Dikᚣita (c.1425-1450), Lord Shiva granted a boon to a Brahmin after his prolonged penance. Accordingly, he would be able to live in water and purify the holy rivers; hence the Brahmin was referred to as Pushkara - the one who nourishes. Upon request from  Brhaspati (Jupiter), when he travelled from one Zodiac sign to another, the Brahmin decided to enter one of the 12 rivers. Pushkar, the person who makes the river holy, travels along with Jupiter from one Zodiac to another. Each of the 12 rivers is associated with a Zodiac sign, and the river for each year's festival is based on the position Jupiter (Brhaspati) in the Zodiac. When Jupiter enters into the same Zodiac zone twice, the second entry will be taken into account. Though Jupiter will be in the Zodiac sign for about a year, the first 12 days called  ''Aadi Puskaram'' are important and lots of people throng the river banks for Pooja, Pithroo Karyam, etc., Last 12 days called ''Anthya Pushkaram''  when it exits the Zodiac sign are considered as most auspicious. A dip in the river will supposedly cleanse a man and remove  all his sins.
On the auspicious day of Pushkarnam, the devotee is supposed to engage himself in five duties such as ''Snana'' (bath in the river), ''Daana'' (charity), ''Japa'' (recitation of mantras), ''Archana'' and  Dhyana (meditation).

The names of 12 rivers vary depending on the  tradition being followed in that region. In Tamil Nadu Pushkaram is celebrated on the banks of Tamraparni, in Thirunelveli district when Jupiter is in Scorpio. In Andhra, it is celebrated across Godavari, Krishna, Penna and Prahita. In Assam, this festival is celebrated on the banks of  Brahmaputra river when Jupiter is in Sagitarus. In  Maharashtra, Bhima is associated with Scorpio sign.

On the final day, Pundits will perform Pooja and Aarthi (showing the  Deepam) to the holy river. Lots of people pay their obeisance to their ancestors (Pithroos) and do ''Pinda Pradhanam"(dissolving the small rice balls sprinkled with gingelly seeds in the river) while Pundits or Purohits chanting the specific mantra.

Ref:
https://en.wikipedia.org/wiki/Pushkaram