Finding an alternative to river sand
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Even as the boom in construction has been pushing up steadily the demand for sand, its extraction from riverbeds is being regulated.
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REGULATED: Damage to riverine ecosystems has led to the regulation of sand-mining.
In the construction sector, sand has always been a tricky thing. Most essential but in short supply, sand is fraught with controversy, as the indiscriminate extraction of it has taken a toll on major rivers in the State.
The demand for sand was estimated at more than 3 million tonnes last year. With the present rate of construction in the State, the demand is on an uphill climb.
As sand is the main coarse aggregate in concrete, helping to bind large pieces of crushed metal with cement, its quality is of paramount importance in construction. Sand should be clean and without salt content.
The main reason for the high demand for river sand for construction in the State is its cleanliness and absence of salinity.
However, continuous and intense exploitation of sand from the beds of major rivers in the State has contributed in a big way to the degradation of riverine ecosystems. There is an urgent need to protect the rivers and rein in their mindless exploitation.
A danger
However, the construction sector vows that in case an abundant supply of quality sand cannot be ensured, building activity in the State can grind to a halt, which may, in turn, affect many ancillary sectors.
The authorities have already imposed severe restrictions on extraction of riverbed sand as a direct response to the concern being raised about the degradation of environment caused by sand-mining.
Legal extraction of sand is now allowed through passes issued by local self-governing bodies such as panchayats and municipal corporations where kadavus (ghats) for sand-mining are located along major rivers such as the Periyar, Bharathapuzha and Chalakudy.
Mining is banned for a couple of months every monsoon, to allow enough time for replenishing the depleting resources of sand on the riverbeds naturally. Later, the passes are issued through a bidding process for each kadavu, controlled by the local self-governing bodies. This is done after hydro-geologists of the Department of Groundwater examine the kadavus. The panchayats and municipalities get good revenue from the fees charged for mining.
Each panchayat or municipality issues 20 to 30 passes a day. The contractor has to pay around Rs. 1,800 for a load on an ordinary lorry and Rs. 2,200 on tipper lorry to the panchayat or municipality. This includes the charges of loading workers.
For two to three months after May, from the onset of monsoon, the permits are withdrawn and mining has to be stopped — on paper, at least. Reality is a far cry from all these statistics. Though panchayats allot only 20 to 30 passes a day, at least 50 loads of sand are transported from each kadavu.
The price of the sand when it reaches the customer is generally decided by a wide range of factors such as the distance of the work site from the river. It also varies from person to person.
Search for alternatives
The shortage and environmental problems have been pointing to the need for a search for viable alternatives to sand.
The Mining and Geology Department of the State Government has been exploring alternative sources.
Even a proposal to explore the possibility of bringing sand from Rajasthan was mooted and studied last year by the department.
The use of manufactured or rock sand is another option being increasingly resorted to by many in the construction sector.
The Kochi-based architect Sebastian Jose points out that manufactured sand is in no way inferior to river sand. His house at Thevara was entirely constructed using manufactured sand. "Strength-wise, manufactured sand is better," he says.
"The use of riverbed sand is very less worldwide, compared to that of manufactured sand."
Jose Antony Kokkad, a former executive director of the Bhagiratha group, is a votary of sea-sand mining.
Mr. Antony vows that sea sand mining, if done judiciously with proper planning, will not harm the environment and will be able to offer quality sand at a cheaper rate. But such a venture will need large-scale capital investment, he says.
The State has, in fact, been debating extraction of sea sand for a couple of years, to tackle the severe shortage of sand faced by the construction sector.
Around 2003, the Kerala State Industrial Development Corporation (KSIDC) came up with a Rs. 180-crore sea-sand mining project, which had raised more than a few eyebrows.
At least a few people see sea and rock sand as alternatives to river sand, claiming that these will be less damaging to the environment than extraction of river sand. However, even the scientific community appears to be divided over the environmental sustainability of the other processes.
While the process of manufacturing rock sand has been known to evoke protests among local communities, sea-sand mining is also a tricky affair, which needs cautious and judicious execution.
RENU RAMANANTH
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