Marabá LA21 Project The city of Marabá, with an estimated population of 177,000 inhabitants growing at a rate of 3,5% per year. The occupation of this area is mostly due to the exploitation of mineral resources which became a very important activity in the economy of the city. Together with the mining industry, the city economy relies also on agriculture, cattle rising, handcraft production and commerce. The city suffers from severe yearly flooding.