International Dredging Review

International Dredging Review

Silt Is Choking Goa’s Progress

By David Murray
Years of crisis and conflict over inadequate dredging in India’s port of Goa have caught up with the state’s plans to increase its mining capacity.

Goa a major source of iron exports from India wants to license 100 new mining leases this year. Yet the state’s port trust announced in April that its waterways cannot accommodate any new traffic according to Goa News.

Goa exported about 45 percent of India¹s iron ore in 2008 much of it to China. The Mormugao Port Trust where ore is transshipped from inland craft to ships for ocean export handled 40.32 metric tons in fiscal year 2009-10 compared to 33.81 tons for the previous fiscal year.Part of the problem Goa port officials admitted is that they have no way of distinguishing legal exports from illegal ones – that is exports from private unauthorized mines.

“We don’t have mechanisms to cross check the source or ore but we have been passing on the entire information about export to the state government and customs” the chairman of the port trust told Goa News on April 5.

In fact mining directly contributes to the silt problem.
Indian environmentalists have criticized Goa’s “mining mafias” for decades to the point where mining companies thought it necessary to set up a Mineral Foundation in 2004 to improve their image by giving money to schools and clean drinking water projects including de-silting projects according to Business Standard magazine.

Environmentalists claim the poorly regulated mines are ruining Goa’s agriculture and threatening its substantial tourist business. Mines use giant excavators that can dig up to 40 feet below sea level depleting the water table then pile soil and other overburden in mounds that wash into waterways (and ruin farmers’ fields) during the rainy season Forbes magazine reported in October.

Piles of iron ore tailings are also dumped directly into waterways contributing to river silting not to mention pollution. An October 2008 article in the online Indian news source asked “whether mining is the backbone of Goa or will it break our backbone in the years to come.”

In March 2009 the Goan government promised to cancel 14 mining leases that were choking the Selaulim dam which provides water to about half a million people in the state.
The Economic Times reported in January that silt and trash from the mouths of Goa’s two main waterways the Mandovi and Zuari Rivers was killing costal coral reefs and driving away diving services catering to tourists. A diving instructor blamed the pollution on the transshipment of iron ore from barges to ocean-going ships as well as on dredging.

The runoff has also accelerated the silting of Goa’s waterways. The dredging crisis in Goa like that in other Indian ports has been recognized for years.
A hydrographic study conducted 10 years ago by the Minor Ports Survey Organization at the request of Goa’s captain of ports revealed that Goa’s main waterway the Mandovi River had become much shallower at many places.

It had last been dredged in 1992 when India’s federal dredging agency Dredging Corporation of India dredged the channel to a uniform depth of three meters.

The repair of a bridge that collapsed in 1986 made the problem worse.

Temporary mud banks built to store machinery were not completely removed after the bridge was finished in 1994 and have allegedly contributed to increased silting.
Debris from the partial collapse of a bridge span during the reconstruction including a 700-ton steel truss was dumped into the river where it remains. The engineering company responsible for the bridge reconstruction has denied it left debris in the river.

In 2004 two scientists from India’s National Institute of Oceanography who had been appointed to a committee formed by the Supreme Court ordered a stop to dredging they called “illegal” and threatening to the river’s ecology.

They charged that the Goa State Infrastructure Development Corporation which had sponsored the dredging had not gotten required permits from another agency the Coastal Regulations Zone.

By February 2009 The Times of India reported that the Mandovi’s navigability “has been drastically reduced.” A port administration official A. P. Mascarenhas told the paper that while all 13 bridge spans crossing the river used to be navigable only four were navigable today.

But officials differ about what is required. Although admitting the need for dredging the hydrographic surveyor of the Captain of the Port Sagar Chandra Rai told the Goa Herald in February that removing sand bars at the entrances of Goa’s three main rivers could cause “disaster” even though the bars restrict navigation.