Hyderabad: As rescuers race against time to save the eight engineers-workers trapped in a 14 km-deep tunnel in the under-construction Srisailam Left Bank Canal (SLBC), officials involved in rescue operations and residents of the locality are beset with unnerving memories.
Exactly four-and-a-half years ago, nine engineers-workers got trapped and died in the Srisailam Left Bank Hydel Power Station nearby.
On Saturday morning, at roughly 9 am, around 40 personnel were working in the SLBC tunnel when a portion of the roof suddenly collapsed. While others managed to run out, suffering some injuries, eight could not exit. With concrete, sludge, water and steel equipment blocking the tunnel path to the mishap site, rescue efforts continued into Sunday.
In a similar incident on 20 August 2020, five engineers of the Telangana State Power Generation Corporation (TSGENCO) and four workers got trapped inside the Srisailam Left Bank Hydel Power Station after a fire broke out due to a short-circuit in a panel of Unit-1 of the 900 MW power plant. Like the irrigation-purpose tunnel where workers are currently trapped, the power station is also deep underground—1.5 km from the surface—which, at the time, made any exit for the employees impossible.
Both the mishap sites are within a short distance of each other, on the Telangana side, at Domalapenta, whereas Andhra Pradesh controls the right bank projects of River Krishna.
“Yes, the two spots are very close, hardly two km or so (as the crow flies),” Vaibhav Gaikwad, Superintendent of Police of Nagarkurnool, the south Telangana border district with Andhra Pradesh, told ThePrint. “But the circumstances are different, and we are hoping for the best, putting every effort to bring the trapped personnel out—at the earliest,” he added.
The 2020 power station fire, which occurred at 10.30 pm, allowed no time for the state machinery or rescue teams to respond and reach the spot. The persistent efforts of the National Disaster Response Force, Central Industrial Security Force, fire department, and teams from the Singareni Collieries to rescue the nine personnel remained obstructed by the flames and thick smoke that engulfed the underground facility at the time. When the teams finally reached the spot through the only tunnel entry-exit point in the afternoon the next day, the personnel trapped inside had died.
“The employees did their best to cease the fire and save the plant despite the danger to their lives. Their efforts were on till 12 am,” TSGENCO, at the time, said in a statement. “The heavy smoke prevented their later attempts to flee through the escape tunnel.”
There were 17 personnel inside the plant—located at the end of a 1.2 km-deep tunnel—and eight had managed to escape. The deceased TSGENCO employees included one deputy engineer, four assistant engineers—one of them a woman—and two plant attendants. Two employees of a private battery firm were also inside the plant for replacement and maintenance.
The then-united Andhra Pradesh chief minister, K. Chandrasekhar Rao, ordered an inquiry by the Criminal Investigation Department to find the reasons behind the accident. The then-Telangana Rashtra Samithi government also constituted a committee, ordering it to recommend measures to prevent such incidents.
“It is very painful for us locals, too, witnessing such incidents. When memories of the nine deaths at the power station are still fresh, it is very unfortunate that another such mishap has occurred now,” Nanda Kishore, a Domalapenta resident who operates a budget resort on the hilly Nallamala terrain, told ThePrint. “We pray the employees come out alive.”
The area is part of the Amrabad tiger reserve.
In the current mishap, all the trapped men are non-locals, including infra firm Jaiprakash Associates project engineer Manoj Kumar and field engineer Sri Niwas—both from UP. Four labourers are from Jharkhand. The two tunnel boring machine operators of Robbins India—Sunny Singh and Gurpreet Singh—are from Jammu & Kashmir and Punjab, respectively.
With rescue efforts underway, Telangana Irrigation Minister Uttam Kumar Reddy has been camping at the site, monitoring the operations. The Revanth Reddy government has sought the assistance of the Army and Navy while also pressing the Hyderabad Disaster Response and Assets Protection Agency (HYDRAA) into the complicated operation.
“In the latest effort, a team of NDRF, SDRF (State Disaster Response Force), police and HYDRAA could reach near the TBM (tunnel boring machine site). There is no communication established from the other side yet. We cannot say what the condition of the men on the other side is. We are exploring all possibilities to reach them,” Gaikwad said Sunday evening.
Describing the situation at the accident site as critical and challenging, and that “water inflow is hampering rescue operations”, Uttam Kumar Reddy said that dewatering is underway and that oxygen is being continuously pumped into the tunnel to sustain the trapped workers.
According to the minister, natural rock formations in the tunnel came loose, causing sudden water and mud inflow, filling about 12-13 feet of the tunnel.
SLBC in the works for over 2 decades
The project to irrigate over two lakh acres in Telangana was initiated in 2005 when Y.S. Rajasekhara Reddy was the united Andhra Pradesh’s CM.
Once completed, the SLBC will become the world’s largest irrigation tunnel without intermediary audits. Of the 44-km-long project, the tunnel boring on a 9.5 km stretch for linking the Dindi reservoir is pending, and the accident occurred there.
Jaiprakash Associates Limited is the project contractor. While the initial project cost was Rs 1,925 crore, delays due to flooding, tunnel-boring machine repairs, etc., have caused the costs to mount to Rs 4,637 crore, according to reports.
Last year, the Congress government in Telangana moved to complete the long pending project meant to water crops in the parched southern and eastern districts. The SLBC tunnel, with its 30 thousand million cubic feet capacity, is designed to deliver 4,000 cusecs of water daily.
In October 2024, Uttam Kumar Reddy instructed officials to expedite the SLBC tunnel works on a war footing and to ensure it is complete by December 2026. According to reports, Jaiprakash Associates and its US-based partners then informed that they were importing critical components to expedite boring.
Work restarted only earlier this week, after a gap of four years. Sources said the tunnel roof at the mishap site had developed cracks and water seepages. On Saturday, the earth gave in, causing the disaster.
Condemning the Bharat Rashtra Samithi leaders for attempting to politicise the SLBC tunnel accident, Uttam Kumar held the KCR government responsible for neglecting the project for over a decade, which, he said, might have contributed to the accident.
(Edited by Madhurita Goswami)
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