HYDERABAD: Hyderabad is currently rejoicing its latest mode of transport — the Metro Rail — and the numerous escalators and elevators (four at each station) which also double up as footover- bridges for the convenience of the public. However, little do they know that these escalators and elevators are not foolproof from water damage. For a city which spends nearly `50 to `60 crore annually on rain-related damages, this can be a costly affair. As a safety mechanism, these elevators and escalators just have a sensor that would shut down the operations in case the shaft pits get flooded.
It may be mentioned here that there are a total of 260 lifts (four each at 55 stations), and 410 escalators (six each at 54 stations) along the 72-kilometre metro corridor. Most of these escalators and elevators are placed at the ground level and stand exposed to rainwater. Speaking about the waterproofing issue, an engineer from Otis, on condition of anonymity, said, “The escalator and elevator systems are not waterproof but use a water sensor that will activate if the pit gets flooded. With long-term exposure to water, the switches and the electrical boards could get damaged. The sensor will stop the escalator and the commuters will have to use them as stairs.
The elevators also have the same working principle.” It’s worth mentioning here that Otis won the contract worth over `420 crore in 2013 and manufactured the escalator and elevator units in their Guangzhou factories in China. After a two year warranty period, the company will maintain the HMR escalators and elevators for a 10 year period. Meanwhile, a senior official with L&T Construction working on the Hyderabad Metro Rail project, said, “The escalator pits are above road level. There is only one along the 72 kilometre stretch that is below the road level.
These pits are watertight and water will only go in if it raises above a particular level. The pits are reinforced with concrete and waterproofed to prevent seeping of water into the pits. But in case if the water goes into the pit it has to be pumped out. In other metros, during monsoon they stop services during heavy rains,” said. Imminent danger? A report by KJA engineering consultants titled “Rising Waters - Impact on Elevator and Escalators “ notes that “escalator and elevator pits are susceptible to flooding as they are the lowest points in a building”.
For elevators, the damage will be reduced to the elevator pit and the components within like guide rails and rail brackets. The buffer systems, like spring or oil buffers, will require replacement. The elevator entrance sills and door equipment could also be affected, but only if water reaches that level. Escalators would ideally shut down once the sensor detects water in escalator pits but in case that doesn’t happen escalator would end up transporting “water throughout the entire unit”, found the report.