 Manufacturing jobs attracted workers from other parts of Mexico and the city's population grew from less than half a million in 1980 to almost 1 million in 1985.In 1972, work began on the first concrete channeling of the Tijuana River; previously the river would flood across a wide plain east and southeast of downtown, inundating an area of wood, cardboard and metal shacks called "Cartolandia" (“Paperland”).The project removed the shacks and added 1.8 million sq.