The public works department (PWD) on Wednesday directed all local authorities in Maharashtra to use at least 20% crushed, artificial or manufactured sand for infrastructural activities in their limits.
The government resolution (GR) in this regard was issued by the department under the guidance of the governor. The GR stated that it was time to shift to environmentally viable options of using artificial sand instead of the natural sand, which is excavated from rivers and creeks for construction purposes, adversely affecting the environment.
A senior state revenue department official said the policy regarding the use of artificial sand, which is made out of crushed stones and boulders, was in place and the department heads must implement it.
“The excavation of sand from rivers has environmental implications, with riverside villages, riverbeds and the ecosystem at large bearing the brunt. Due to this, erosion happens upstream or downstream of water bodies due to change in the velocity of water flow, affecting the riverbanks, land and structures. The groundwater and water table are also impacted due to the excavation of sand,” geologist Suyog Jagtap from the Directorate of Geology and mining said.
Jagtap, also the former Pune district mining officer, was a part of the committee to decide on use of artificial or manufactured sand. “It is the need of the hour as vast infrastructure works are being undertaken in the state,” he said.
“There is a need to increase awareness about use of artificial or manufactured sand among people as this will help reduce the burden on sand excavation from the riverside. Especially in the western parts of the state, most rivers are under tremendous burden as their river channels suffer due to the excavation of sand, impacting their eco-system and environment at large,’’ Jagtap said.
Mahesh Makawana, associate professor in civil engineering from MIT College in Kothrud, reiterated the use of artificial sand. “Why just 20%, the artificial sand can be used for the entire construction activity. It has been made mandatory in many states. As for the quality, the use of artificial sand doesn’t hinder the quality of construction in any way,’’ he said.
PWD officials alleged that powerful sand mining lobbies most often have links with politicians. “People involved in illegal excavation of sand had also tried to mow down revenue officials when they tried to stop them. These people violate all the norms, including the quantity of sand to be mined and number of dredgers to be operated,” a PWD official said.
The cost of artificial sand depends on the distance from the site of the crushing to the end-use location. “If the site is nearby, the price is almost on par or close to that of natural sand,” the official said.
Several developers in Delhi, Mumbai, Pune, Bangalore, Chennai and Kerala have already switched to manufactured sand in construction activities,’’ a city-based realtor said.
What can be gained?
As per experts, it is highly cohesive and compressive in strength. “It has lesser impurities that helps in producing better quality concrete. Nearly 30% increase in masonry strength can be obtained obtained with the use of manufactured sand,” an expert said
Using manufactured sand also requires lower water-cement ratio, which also results in better characteristics in the hardened state. “Manufacturing sand also eliminates environmental impact occurred due to lifting of natural sand from river bed,” the expert said.
Experts said the manufactured sand should be strongly recommended to be used in the real estate sector. “It is recommended as a substitute for river sand in production of concrete and mortar mix, which can be used in any kinds of concrete member and masonry work in any industry,” an expert said.
