Kaveri Kumar | September, 2002

The impressive Port of Kolkata (Calcutta) has played a significant role in the history of India. Environmental measures are now being carried out to breathe new life into the old port.

	Kolkata's fresh water discharge in the sea is growing problem for its port

Built by the British colonial rulers, Kolkata Port is the oldest in the country. As the only major riverine port in India, it ranks fourth in terms of cargo handling and serves the maritime activities of east, northeast and northern India, in addition to land-locked neighbours - Nepal and Bhutan.

Some 232 kms from the coast makes it one of the longest pilotage distances in the world. Unlike Rotterdam, as the world's biggest, Kolkata Port has a particularly complicated approach from the sea. Ships have to change direction almost to the point of making u-turns, says Dr. Jurgen Suendermann, advisor for a project to improve the draft of the estuaries of the Hooghly River in Kolkata.

This project has been taken up by the port authorities. Like all riverine ports, it has to endure certain perennial problems. There is consequently a constant struggle with nature to keep the navigation channels from the sea to the port open throughout the year.

Barrage of tides
"The variable fresh water discharge of the river due to the monsoons increases the navigational challenge, which is non-existent at Rotterdam," says Suendermann. The situation is further complicated by the presence of 17 sandbars. Siltation is naturally one of the major problems. Coupled with it is the alluvial nature of the riverbed material and the unpredictable geo-morphological changes - especially in the esturian region. Besides, it often has to bear the brunt of very strong tides, though the problem due to bore tides has diminished since the commissioning of the Farakka barrage.

The problem requires large-scale lifting of silt. Kolkata Port has one of the highest rates of silting in the world, though it is not the same in the case of dredging, says Suendermann. However, the intensity of the problem is seen in the dredging figures of the past few years. In 1985-86 it stood at 12.54 million tonnes, in 1991-92 it was 18.29 million tonnes and in 1998-99 to 25.21 million tonnes. Intensive efforts to increase the navigational draft have led to the involvement of Dredging Corporation of India.

To train a river
Maintenance dredging is now being carried out in the estuary of the river to provide better draft for Haldia, 104 km downstream where the deep-water dock system of Kolkata Port is situated. In addition, capital dredging has been undertaken in the Indian Government's 9th plan for an estimated expenditure of Rs. 235 crore (US $ 48 million). It comprises "river training" measures, construction of a southern guide wall, silt trapping and river protection work, including shore disposal, along with construction of a 2.8 km long guide wall cross-spur at the northern end of Nayachar Island.

The measures envisage a draft increase of one metre upon completion. With the commissioning of the Farakka barrage, the bars of the upper reaches 75 kms from Kolkata Port to Diamond Harbour downstream have stabilised considerably. The problem has now shifted to the channel from Diamond Harbour to Sandhead 157 km downstream.

Dredging alone cannot be the solution. The port authorities have taken up a massive afforestation project at Nayachar Island in the downstream and the Haldia river bend. Around 200 hectares have been brought under the project, in which different types of mangrove, associated species and salt-resistant varieties are grown. Afforestation, along with environmental upgradation, help check soil erosion. The port authorities now claim that the draft had increased to above 7m on 157 days in 2001-2002 against 104 days in 2000-2002 at Kolkata dock system and above 8m for 280 days at Haldia in 2001-2002 as against 246 days the previous year.

The port needs to be nurtured in order to develop adjacent areas. The fact assumes greater importance in view of the fact that the government seeks to project Kolkata Port as the gateway to south Asia in the near future.

Kaveri Kumar is Kolkatta-based journalist.

For more information, visit the following sites:
Kolkata: http://www.calcuttaweb.com/
Nepal: http://www.calcuttaweb.com/
Bhutan: http://www.kingdomofbhutan.com/
Farakka: http://www.cyberbangladesh.org/disaster.html
Dredging Corporation of India: http://www.dredge-india.com/
Afforestation: http://gis.joensuu.fi/research/maaseutu/abs1.htm
Hooghly: http://www.cs.albany.edu/~amit/ganges.html