tonnes (April-September, 2012) from 448 million tonnes (April-September, 2011), according to the latest data.
The rise in cargo traffic during the same period last fiscal was 5%.
"This 1.8% increase is mainly attributable to a decline of 3.3% in the cargo handled at major ports (which handle heavy traffic)," it said.
In contrast, non-major ports' growth increased to 185.206 million tonnes or 10.3% in the first half of 2012-13 compared to 168 or 8.2% in the corresponding period of 2011-12.
There are 12 major ports in India -- Mumbai, Jawaharlal Nehru Port Trust (JNPT), Kolkata (with Haldia), Chennai, Cochin, Paradip, New Mangalore, Marmagao, Ennore, Tuticorin, Kandla and Visakhapatanam.
During first six months of 2012-13, Ennore port recorded the highest growth in traffic (22.5%) followed by Mumbai (8.0%), Kandla (7.5%), NMPT (4.3 per cent) and Cochin Port (3.9%).
Negative traffic handling was reported by Marmagao (-22.9 per cent) Haldia (-17.9%), Vishakhapatnam (-16.0 per cent), Paradip (-8.5%), Chennai Port (-7.3%) and Kolkata (-7.8%).
During the first six months of 2012-13, coal, container cargo, other cargo, and petroleum oil and lubricant (POL) traffic posted growth of 3.8%, 2.7%, 2.4 per cent and 0.5% respectively.
The survey said the traffic in iron ore was affected during April-September 2012, recording a negative growth of 43.1% due to ban on mining of iron ore.
Total container traffic at major ports increased in terms of tonnage by 2.7% during April-September 2012 and JNPT emerged as the leading container-handling port with a 48% share in terms of tonnage.
Last year's Economic Survey (2011-12) had projected an investment of over Rs. 1.5 lakh crore in the country's ports sector in the next five years.