Heavy water leakage has been detected from the Mahim-Kelwa dam at Zanjroli in Palghar district, Maharashtra causing danger to a few villages situated downstream, officials said on Saturday, Jan 8, 2022.[i] A massive three-metre breach was detected on Saturday morning in a 41-year-old earthen dam with a 3.34 Million Cubic Meters capacity at Zanzorli in Palghar.[ii] About 1200 litres per minute was being discharged downstream.
A letter sent by Under Secretary (Disaster Management Unit) K Suryakrishnamurty to the NDRF Commandant, 5th Battalion, Pune on Saturday stated: “As per information received from District Disaster Management Authority, Palghar, due to heavy leakage in Mahim Kelwa dam, the villages downstream from the dam are likely to be in danger. The district administration has requested team from NDRF for evacuation of villagers as a precautionary measure in this situation. In light of the above, you are requested to immediately depute one team at Palghar district.”[iii]
“We first noticed a minor leakage in the (outer side of the) dam during the pre-monsoon period and the leakage increased during the monsoon in July,” said Prabhakar Giri, deputy engineer, Irrigation Department Palghar. They informed the Dam Safety Organisation (DSO) of the Irrigation Department at Nashik and the diver went underwater to videograph the situation. They said they wanted the monsoon to be over to start the repairs of the dam, but noticed the breach on Saturday.
According to officials, some leakage on the outer side the dam at Zanjroli was reported during the monsoon. “The irrigation department was informed about the leakage… The executive engineer of dam safety department (Nashik) had also conducted field inspection on January 4, 2022 who had given necessary instructions to stop the leakage… Steps were being taken in that regard, however, the leakage increased,” the official said. The Executive Engineer reported instructed to bring down the water level behind the dam, but it is not clear if they did that.
The dam will be repaired by placing sand and other materials where the breach has been found, to control the seepage, informed Giri. He added that the dam supplied water to 17 gram panchayats. Some photos here are taken from news video[iv].
As a precaution, the district administration has started evacuating five villages namely Zanzorli, Bandate, Dondhalpada, Patharipada and Navinpada and deployed teams of NDRF and SDRF to tackle any eventuality in case the dam bursts. The Disaster Management Unit under-secretary K. Suryakrishnamurty has requested for another NDRF team.
The Mahim Kelwa Dam The Mahim-Kelwa dam is located around 100 km from Mumbai, at an elevation. Other villages below the dam have been put on high alert. The Palghar Irrigation Department executive engineer has ordered round-the-clock monitoring of the dam condition and directed for all necessary measures for the safety of the villagers falling in its path and also shift them to safer locations. The dam is a popular picnic spot for people from Mumbai, Pune and south Gujarat, with the surrounding forests a favourite with bird-watchers for the large number of species.
Salient Features of the Dam As per National Register of Large Dams from CWC:
Dam Name: Mahim Kelwa
Longitude: 72° 49′ 30″
Latitude: 19° 38′ 00″
Year of Completion: 1981
Ht: 17.8 m
Length: 844 m
Gross Storage Capacity: 3.399 MCM
Effective Storage Capacity: 3.243 MCM
Reservoir Area; 65.2 ha
Design Spillway Capacity: 207 cumecs
Many Questions, no answers A lot of question arise based on the information available so far. If a leak in the dam was noticed in pre monsoon period, what has been done so far to ensure that the earthen dam does not lead to disaster? Particularly knowing that Palghar is known to have rather heavy monsoon rainfall? If the repair was to start after the monsoon, what has been done so far, the monsoon has been officially over for over 10 weeks. If the EE had asked for reducing water level in the dam after Jan 4, 2022 visit, what had been done so far? If the dam had a leakage since pre monsoon period, why was the dam filled up at all? Who are responsible, answerable for this situation?
The whole episode reminds one of the Tivare dam disaster near Pune in July 2019[v]. The report of the committee set up after that disaster is not even in public domain. We are destined to face repetition of such dam disaster till we improve governance of our dams. Clearly Dam Safety Bill passed by the parliament in 2021 is not going to be of great help here as it hardly makes any changes in the governance of dams or dam safety.
POST SCRIPT: Jan 10, 2022: The massive three-metre breach has been successfully plugged by the Irrigation department on Sunday morning. This has averted the evacuation of 1500 people of five villages. “Around 300 dumpers of sand and other materials were dumped near the jack well where the breach was noticed to control the seepage,” said Prabhakar Giri. The civil work will be completed by Tuesday, Jan 11, 2022.
– This is a temporary measure and a permanent measure will be taken during the summer season when the water level will be less, said an official. “We believe that a 40-year-old cement pipe may have developed holes or may have been dislocated near the jack well, resulting in the seepage. We will install a 125m high-density polyethylene pipe without disturbing the present structure to avoid further leakage,” said the official. “As a long term plan, if need be, we may construct a new jack well at the present site,” he added.