It has an average elevation of 75 metres (246 feet).
As of 2001 the Indian census, Vallam's population numbered 14,495. Males constitute 48% of the population and females 52%. Vallam has an average literacy rate of 73%, higher than the national average of 59.5%: male literacy is 77%, and female literacy is 69%. In Vallam, 11% of the population is under 6 years of age.
Four mosques operate in central Vallam.
Eid Ka Masjid is situated on the highest hill, some distance from the jummah- masjid and market arena. Every year, Eid-Ul-Alha is held there. This mosque is over 150 years old.
One of the mosques, known as Mela Pallivasal, situated near anna statue near market arena, is built with white marble. More than 100 years old, it is the oldest masjid in the village.
Friday prayer is popular in Jummah - masjid near the bus terminal. Eid-Ul-Fithr (Ramzan) celebrations are an important aspect of this masjid as it is large enough to hold thousands of devotees.
Another important aspect is the Tawakalshah-Durgah, a religious leader's graveyard, which has been in Vallam for more than one hundred years.
A new mosque in Vallam opened for prayer in July 2013. This mosque has a capacity for 100 worshippers to pray at a time and is located in the Anna Nagar area of Vallam.
A traditional Christian church, over 50 years old, is located near the bus terminal. The church has a famous history with a school associated with it.
Agowri Amman is a 1000- to 2000-year-old temple in Vallam. Mother Agowri graces in the temple with two heads sitting on a lotus shaped Peeta. One face is ferocious, with long and sharp teeth showing her destructive side against the demons. The other above is calm, smiling and all graceful protecting the devotees and righteous from evils. The Mother has different weapons in Her eight hands and also a parrot representing Mother Parvathi. Sri Chakra, being an important form of Shakti worship, is installed under the feet of Mother.very powerful goddess.
Last Friday of Aadi month and Aadi Perukku (July–August), New Moon and Full Moon days are celebrated in the temple.
Maha chandi homam conducted every year during chithra pournami( full moon day) time.
Vallam is known for many educational institutions for higher studies. It has two Deemed Universities in its town limit. They are Periyar Maniammai University and PRIST University. Both these universities are predominantly engineering courses based. Periyar Maniammai University and PRIST University were initially started as Engineering Colleges, later they have been deemed as Universities under UGC Act. Vallam also has many colleges in its town limit, they are Adaikalamatha College, Swami Vivekananda College, Maruthupandiar College, Ponnaiya Ramajayam Engineering College and Periyar Polytechnic College.
The Vallam selection grade town panchayat near here has taken the lead in environment protection. Roads using plastic wastes ranging up to a distance of 1,075 metres were laid.