The construction industry in Kerala, the land of rivers, is witnessing a fast widening gap in demand and supply of river sand.
Natural sand has become a costly, precious commodity. With construction activities gaining rapid pace in the State in the past two decades, this river resource has been exploited excessively.
Almost all major rivers in the State have been degraded owing to aggressive sand-mining.
Indiscriminate mining has been posing an alarming threat not only to the river systems but also to the State's socio-economic life.
The so-called ‘sand mafia' thrives in different parts of the State in a desperate run for fast money, making life miserable for the common man.
Environmental groups across the State have been clamouring for action against the ‘sand mafia' and checking illegal sand-mining. Environmentalists have been pressing for a ban on mining by promoting one or the other alternative to sand for construction purposes.
Builders use different grades of manufactured sand, or ‘M-Sand,' as an alternative to river sand in various parts of the State.
Damage to the hills
Environmentalists are of the opinion that indiscriminate production of ‘M-sand' will destroy the hills and rocks, ultimately leading to irreparable damage to the environment and the ecosystem as a whole.
N.K. Sukumaran Nair, general secretary, Pampa Parirakashana Samithi, and V.N. Gopinatha Pillai, general secretary, Manimalayar Samrakshana Samithi, say the government should take the initiative to check illegal sand-mining and promote alternatives to natural sand for use in the construction industry.
Mr. Nair said the riverbeds of the Pampa and the Manimala have gone down by six to eight metres and salinity intrusion has been recorded up to the Kozhencherry course of the Pampa.
Of late, builders in Central Travancore region have started using silica sand, a byproduct of the cement industry, for construction purposes.
Biju C. Thomas, a Chengannur-based structural engineer, says silica sand can be a better alternative to river sand. M. Elamthendral, engineer at Associated Cement Company, told The Hindu that the Eco Sand brand introduced by the company is cheaper than river sand. It costs Rs.80 a cubic feet and is available in 50-kg bags and as lorry loads for offloading at the worksite.
River sand costs Rs.120 to Rs.140 a cubic feet and M-sand Rs.55 a cubic feet.
Mr. Elamthendral says Eco Sand is a durability improver. It is finely powdered crystalline silica, which can replace 100 per cent of the conventional sand usage in concrete and mortar.
G. Sreekumar of S.J. Hardwares, a Thiruvalla-based Eco Sand dealer, says its demand and sale is fast picking up in central Travancore. Builders opt for Eco Sand, as it ensures a comparatively denser concrete and mortar than those made only with conventional sand with or without quarry fines.
Fewer pores
Mr. Elamthendral says the micro-filling effect of Eco Sand reduces pores in concrete and provides better moisture resistivity and thus durability. Moreover, Eco Sand is substantially cheaper, reducing the construction cost.
The non-absorbent nature and the smooth surface texture benefit workability and reduces water requirement. He says that Eco Sand has been tested safe at the National Institute of Technology, Kozhikode, against the limits of deleterious materials and soluble silica for alkali aggregate reactivity.
Mr. Thomas and Mr. Nair say it is high time the government promoted eco-friendly and cost-effective methods of construction to check further degradation of nature and to protect Mother Earth.
