For 100 years now, Walwan dam has stood across the Indrayani river, not far from Lonavala. A source of hydro-electricity in the region, the dam was set up after Jamsetji Tata envisioned that clean energy would power industry, particularly the cotton mills. That dream was eventually realised by his son Dorab Tata, who laid the foundation stone of Walwan dam on February 8, 1911.
But industrial growth wasn’t the only thing on the mind of the Tatas’. At the foundation-laying ceremony, Dorab Tata was quoted as saying: “Just for a moment think what a glorious city Bombay would be if freed from smoke.”
Today, Walwan dam stands 26.63 metres high (above the lowest foundation), 1,356 metres long with a storage capacity of 72 million cubic metres. Initially, the capacity of the dam was 40 MW but as technology progressed, its capacity today is 72 MW.
Back in the day, it was a near-impossible task to ask industrialists to switch their power source from coal to water. There was palpable scepticism about hydro-electricity. Eventually, few saw the potential of the project and conceded to the switch.
The electricity generated was primarily transmitted from Khopoli to Parel to run the cotton mills. In the later years, the role of the dam was modified and now the electricity is also used by households in Lonavala and villages nearby.
The relocation of the people was a comparatively peaceful process. It didn’t create the upheaval that the latter projects did. M Paranjape, chief of hydro power for TATA Power, says: “The entire land acquisition process was carried out smoothly and people were compensated for their houses and temples and everything.”
The location was ideal owing to Lonavala’s rainfall and topography, and civil engineers proposed the construction of artificial lakes at high altitudes where rainwater could be stored and later used for generation of hydro-electricity. The water from the high-altitude dam is directed to Khandala plateau through open duct lines and from there it is sent to the Khopoli hydro-electric power plant through pipelines.
A project of this magnitude required excessive funding and the entire capital for the dam was raised by Indians, from maharajas to the common man, according to the company’s records.
It took the combined effort of 7,000 men who toiled in the difficult ghat terrain, laying pipelines, carrying raw materials and erecting the transmission towers to complete the project. In a time period when the comfort of roads was unknown, the hilly terrain of the ghats saw workers laying giant tubes on surfaces that dropped 90 degrees straight to the bottom.
During the recent drought years in Maharashtra, water from the dam was given to Khopoli municipality for supply as drinking water.
Paranjape says, “What we do is we impound water during monsoon and use it during dry season. So the building was done in such a way that nobody gets affected downstream of our plant.”
It has become a well-known tourist spot given its tranquil and picturesque location. Tourists and locals alike visit the Walwan lake, often in search of new trails to follow, new spots for picnicking or just a quiet place to stop at before moving on to other destinations.