The Municipalità di Marghera, one of the six boroughs of Venice's comune, includes 30,000 inhabitants (Marghera alone includes 17,000 inhabitants).
The name "Marghera", comes from the fact that the area where the present city was built, was once a marine swamp. In the Venetian language, in fact, "Mar gh' era" means "There was the sea".
By the start of the 20th century it was obvious that Venice's existing port at Bacino San Marco was incapable of servicing large modern ships. A new port was constructed at the western end of Venice at Stazione Marittima. However, it became obvious that if industry was developed in its immediate vicinity this would negatively impact on the historical city and tourism. As a result, by 1917 – during the First World War – the Italian government had decided to develop an industrial zone and state-of-the-art port at Marghera on the mainland opposite Venice and near the town of Mestre. A major backer of the scheme was Count Giuseppe Volpi. Development commenced in 1920, and for 10 years dredging of shipping channels, excavation, and land reclamation took place. A residential area was also constructed for the zone's workers. In 1923 the first chemical factory commenced production. The number of workers employed in the zone rose to 6000 by 1930, 16,000 by 1950 and 35,000 by 1970.
In 1926 Marghera and Mestre were made a frazione under the control of the municipal government of Venice. By 1940 more than 60 factories were established at Marghera, and as a result during World War II Allied bombers targeted Porto Marghera.
The Enichem fertilizer company operates in Marghera.