Khadakwasla Dam

Panshet Dam was nearing completion in July 1961,[14] designed essentially to regulate the supply of water to Khadakwasla Lake, in such a manner that the huge reservoir would have more than adequate water for the people of Poona (Pune). The reservoir is the source of water for the two canals referred to above that start at Khadakwasla. The right bank canal is 112 km (70 mi) long and irrigates about 45,000 hectares (170 sq mi) of land in Pune district and the villages around Haveli, Daund, Indapur and Baramati, while the left bank canal supplies drinking water to Pune, Kirkee and surrounds.[15]

Panshet Dam was zoned at a height of 51 m (167 ft) with impervious central core outlet gates located in a trench of the left abutment; hoists were not fully installed when floods occurred at the site of construction. The reservoir had a capacity of 2.70 million cubic meters. Between 18 June – 12 July 1961, the recorded rainfall was 180.3 cm (71 in), stressing Panshet dam to its limits.[16] The average rainfall for that period is 125–130 cm (49.2–51.2 in).[17]

Khadakwasla Lake was already 90% full, with water flowing in freely from Varasgaon, besides the abundant rainfall. The people of Pune had no inkling of their fate. The rain caused such a rapid rise of the reservoir water level at Panshet that the new embankment could not adjust to the dangerous loading condition. Water rose at the rate of 9 m (30 ft) per day initially, and 24 m (79 ft) in 12 days. Due to incomplete rough outlet surface, the flow through was unsteady which caused pressure surges. Cracks were formed along the edges of the right angles to the axis of the dam causing a subsidence 9 m (30 ft) wide, leaving the crest of the dam 0.6 m (2.0 ft) above the reservoir level on 11 July. The failure was attributed to inadequate provision of the outlet facility during emergency. This caused the fateful collapse of the structure above the outlets.[16]

Panshet Dam had been cleared for construction under the aegis of the Bombay State Irrigation Department. When the State split into Maharashtra and Gujarat in 1960, Panshet Dam came under the supervision of Maharashtra State Irrigation Department. Mr. SM Bhalerao was the executive engineer in charge of Panshet dam, and Mr. MR Panse (both deceased), the plant engineer. They were running out of time, since this project was their first major assignment and the area of work hostile. Former secretary of the state irrigation department, Madhukar Deshmukh, who had worked as a deputy engineer at Panshet dam till late 1959, explained what actually went wrong. According to him, the dam was planned as a fully earthen one with a height of 61 m (200 ft). Given the nature of the dam, an outlet to the downstream Khadakwasla reservoir was created at its base. Deshmukh said, "Ideally, the arch of the conduit should have been made from RCC. However, in those days, steel was in short supply and we were forced to use concrete blocks instead." The force of the water was so great that it managed to dislodge the concrete blocks, which resulted in the earthen portion of the dam giving way.[18] They had made a desperate appeal for help and manpower augmentation, and the Area Commander, Southern Command, Lieutenant-General Chaudhari reacted swiftly, keeping Commandant NDA, Rear Admiral BA Samson in the loop. Assistance was provided using a semi-prepared road from Peacock Bay, NDA to Panshet along the Mutha river/backwaters of Khadakwasla Lake and also via Mulshi Lake. Engineering officers from BEG, College Of Military Engineering (CME) and close to 3,000 personnel moved out just after sunset.

3,000 soldiers from the Bombay Engineer Group and Centre (BEG), the College of Military Engineering (CME) and other units were dispatched by HQ Southern Command, Pune, to help. They formed a human chain at Panshet Dam, as Army and commandeered civil trucks brought sandbags by the tens of thousands to shore up Panshet Dam. The engineers were certain the dam would collapse; they were praying that the Armed Forces personnel's aid would delay the inevitable to dawn, so that the people of Pune could be warned in time and those living on the banks of the rivers Mutha and Mula could be evacuated. Despite their best efforts, Panshet Dam caved in at 0330 hrs on 12 July 1961. Khadakwasla Dam was the last barrier.[19] The dam stood firm till well past dawn, contributing to the safety of residents living downstream in the vicinity of the path of least resistance to the surging freestream water.

It took another four hours for Khadakwasla Dam to breach, causing devastating floods in Pune. A 120 m (390 ft) central section of the dam gave way.[13] Word had been passed around the few people living on the swampy land next to the two canals early in the morning. The authorities started moving out the residents living near the riverside. Many residents fled to higher grounds, some all the way to the Parvati Hill. Apparently, All India Radio did not broadcast any warnings, and was playing a regular scheduled music program when the floods struck. The low-lying areas of the old city were almost completely submerged. Except for the rail bridge of the Sangam Bridges, two adjacent bridges built separately for rail and road traffic and Bund Garden Bridge, all other bridges were under water as well. Water rushed into the old ‘Peths’ and along Karve Road, Deccan Gymkhana areas. For many hours, the high water levels persisted. Roughly speaking, Panshet water reservoir stores enough water for all of Pune’s city needs today (today’s needs are probably 8-10 times more than the requirements of the 1960s).

After the water receded fully, some three days later, the stench of the aftermath of flooding stayed on for nearly three months. A large number of people sold their land and houses at rock-bottom prices and moved away. Pune's development plans were put on hold till normalcy was achieved. Bhalerao and Panse were blamed for oversight and lack of common sense in not constructing a wide reinforced archway in the centre of the mudwork dam for water to flow through.[18] The old riverside city landscape changed forever. New localities (such as Lokmanya Nagar, Gokhale Nagar, etc.) were set up to resettle some of the flood affected citizens. Most of the bridges were damaged and needed fixing and in some cases complete rebuilding.[20]

The dam was later rebuilt over four years. In this period, residents of Pune and its suburbs had to face water rationing. While Pune city, Camp and Cantonment area were not too severely affected, people in Khadki (Kirkee), Dapodi, Bopodi, Phugewadi, Hadapsar, Shivajinagar and Deccan Gymkhana had limited water supply.[21] At the National Defence Academy (NDA), Peacock Bay, the Naval cadets training section and the lakeside guest rooms were submerged. The view from the NDA Commandant's house, which overlooks the entire lake and dam, was distressing.