SRI LANKA: Green-friendly Move May Not be so Green after All

By Feizal Samath Reprint | | Print |

Feizal Samath

COLOMBO, Feb 18 2003 (IPS) - What the Sri Lankan government took as a green-friendly step this month – the use of sea sand instead of exploiting river sand that has put the environment under threat – may not be so green after all.

Earlier this month, the government decided to promote the use of sea sand for the construction industry to curb the rampant use and overexploitation of rivers.

But environmentalists say this is far from a foolproof shift, saying there may well be equally negative effects from using sea sand. A proper environmental survey must be undertaken before large-scale dredging of the seabed takes place, they add.

”We don’t know whether this is good (sea sand) or that is bad (river sand) until a proper environmental impact assessment (EIA) is undertaken. We should not have piecemeal decisions on important issues like this, noted Prasanna Weerakkody of the Nature Conservation Group.

Overexploitation of rivers has caused not only a shortage of sand but damage to the nearby environment in this South Asian island nation, which relies heavily on river sand for construction purposes.

Janapriya de Silva, chairman of the state-owned Geological Survey and Mines Bureau, says sand mining in riverbeds is weakening riverbanks and the foundations of bridges and causing an incursion of seawater upriver. ”We could run short of sand in another two years’ time, he told the ‘Sunday Times’ newspaper.

The problem became so acute recently that with last year’s drought, a key water pumping station at Avissawella outside the capital Colombo was closed down because of seawater incursion.

But environmentalists say the government must also keep in mind that when large-scale dredging of the sea takes place, fish stocks get depleted, marine life dies and most of the fish move to the deep sea – away from the reach of traditional fishermen.

Two years ago, three fishermen were shot dead during a protest against sea sand mining – off the western coast for a major construction project – which had affected the livelihood of dozens of families as fish stocks ran out.

Suranjan Kodituwakku, organiser of the Green Movement of Sri Lanka, says that when some 500,000 metric tonnes of sea sand was mined to build a northern highway from Colombo, massive dredging machines were used off the southern coast.

Mining work and the sounds scared off the fish, depriving some 150,000 families of their income.

Still, government officials are working to allay a range of concerns about using sea sand, including fears by some environmentalists and users that it is not suitable for construction purposes because of high salt content.

”Studies at the Moratuwa University (outside Colombo) show that the salt content in dredged sea sand is 0.8 percent within the acceptable limit of less than one percent. So it is acceptable for construction purposes,” said Dr N P Wijeyananda, director of the Geological Survey and Mines Bureau.

But beyond the technical qualities of sea sand, Hemantha Withanage, executive director of the Environmental Foundation Ltd (EFL), the country’s top environmental group, says there are bigger issues to be addressed first.

”We must have an EIA before any firm decision is taken on sea sand mining, Withanage added.

”If there is no choice in the matter, at least steps should be taken to mitigate the environmental impact. For this, a proper environmental study has to be undertaken, he said.

The demand for sand is expect to rise sharply soon due to a construction boom expected from economic revival spurred by the year-long ceasefire between the government and Tamil Tiger rebels, and hopes of a permanent settlement of the 20-year old ethnic conflict.

Meantime, De Silva from the state-owned bureau said: ”We want to promote the use of sea sand among the biggest users such as construction firms. What we want to stop is the overexploitation of rivers. We must strike a balance otherwise the country will face a crisis.”

Noel Vithanage, a marine resources researcher, said that the dredging process is expected to take place several kilometres offshore with two feet dug into the sea.

But, he said, this would disturb a lot of marine life that lives on the seabed, ornamental fish and mollusks, which are exported. ”By pumping seawater with the sand onto land, this could change the mineral context of the water table and affect animals on land, Vithanage added.

The Geological Survey and Mines Bureau says it now allows dredging at selected sites off the south coast some 20 kilometres offshore and at a water depth of over 15 metres.

Large deposits of sand with the properties required for building purposes are found in the middle and lower reaches of several of Sri Lanka’s main rivers. Sand along riverbanks is mined using manual labour and buckets and wicker baskets, while deeper water sand is mined by divers who load it onto barges.

Weerakkody from the Nature Conservation Group says that while the loss of river sand halts the river flow that enriches the beaches and balances erosion, sea sand mining could ruin all life forms on the seabed.

”Either way, if you dig the top of the seabed or deep into the seabed, it could damage some form of marine life, he said.

Bringing a lot of seawater to shore can affect the mineral content on land, causing wells to turn salty, for instance.

Said Weerakkody: ”It’s a difficult choice. There are environmental problems from mining for river or sea sand. What we need to do it to find ways of minimising the impact and that’s possible only through a proper environmental survey.”