There are approximately 1,140 detainees in the six temporary prison camps in Kokrajhar, Goalpara, Jorhat, Tezpur, Dibrugarh and Silchar.
Spread over 10 acres (4 hectares), the Matia camp will have a hospital, an auditorium, a common kitchen and 180 toilets.
"We will see if children detainees can also be provided with educational facilities," Rabin Das, a local engineer overseeing the construction work, told DW.
In 2014, when the Supreme Court of India directed the authorities to begin the process of updating the 1951 version of the NRC, many, including members of the ruling Hindu nationalist Bharatiya Janata Party (BJP), believed it would provide what is being referred to by the right wing on social media as the "final solution" for Assam's illegal immigration problem, especially from neighboring Bangladesh.
The BJP, led by Prime Minister Narendra Modi, has long opposed illegal immigration to India. In recent years, the party has intensified its campaign for the NRC. But critics say the NRC process reflects the BJP's goal to serve only co-religionists.
Earlier this year, the central government in New Delhi also passed the Citizenship Amendment Bill, which relaxed conditions for non-Muslim immigrants, including Hindus, Zoroastrians, Sikhs, Buddhists and Jains from Afghanistan, Pakistan and Bangladesh to get Indian citizenship.
On August 1 this year, the Assam government published district-wise data of included and excluded people in the draft NRC and the results were surprising. The highest rate of exclusion was recorded in the Hindu-majority Hojai district (32.99%), whereas Muslim-majority districts like Karimganj, Dhubri and South Salmara, which share their borders with Bangladesh, recorded much lower rates of exclusion.
Those who have been left out of the list have 120 days to appeal to the Foreigners' Tribunals against their NRC exclusion. Over 200 new tribunals are also being set up across the state so that these people can challenge the NRC.
Meanwhile, the authorities want to make sure that the construction work at the Matia detention center won't be delayed.
"Sometimes we have to work 12 hours a day, for which we receive 300 rupees (€3.8, $4.2). It is a tough job, but the contractor has set deadlines for the construction," Noor Ali, a local labourer, told DW.
Ironically, several laborers at the construction site are not on the NRC list and are worried about their future. Many of these people are extremely poor, illiterate and belong to the Muslim community.
"I have been working at the site for over six months. I was very worried when I found out that my name was not on the list, but now I am hoping that everything turns out well. What else can I do?" Qasim Ali, a construction worker, told DW.
Many people excluded from the list don't have the financial means to fight lengthy legal battles. Most of them also don't have the documents that can prove their right to citizenship in the country. They fear they will end up in these under-construction detention centers.