Canals and elevated ducts were constructed to divert river water, which improved groundwater levels and the availability of a fundamental resource: drinking water.
Forests now extend from Vijayapura's northern tip to its rural outskirts in the south.
Vijayapura's district administration credits the tree cover with cooling temperatures in the area by at least 0.6C from 2017 to 2023, according to state government data.
Endangered black bucks, leopards, snakes, and several species of birds have become a common sight.
The project began in the summer of 2016, when Karnataka's overall forest cover was about 20%.
M.B. Patil, the Karnataka state water resources minister at the time, learned from a forest official that Vijayapura had a forest cover of only 0.17%.
"I thought he made a mistake," Patil said in an interview. "That day, I thought we should do something about it."
Patil worked with forest officials and other nature lovers to concoct a plan.
A public-private partnership invested nearly 2 billion rupees ($37 million) in building forests. A non-profit was set up to circumvent lengthy government processes.
Forest officers identified land for planting hundreds of thousands of trees over the next 10 to 15 years. And 14 new government nurseries provided saplings.
The nurseries grew more than 200 tree species native to the region, from banyan to tamarind. But Some farmers were reluctant to plant tree varieties that did not generate immediate returns.
"So, we asked them: What saplings do you want?" Santosh Ajur, a local forest officer, said. Their responses led the Government to begin raising java plum, mango, neem, and other tree varieties with fruit that could go right to market.
"Suddenly," Ajur said, "we had people queuing up for hours to get the saplings they wanted."
Farmers were given incentives to plant trees on thousands of hectares of private land.
The forest department gave out free saplings or sold them at a subsidised rate of less than 10 rupees.
To maximise the rate of survival, saplings were grown in 25kg to 80kg bags that retain soil and moisture.
The Government oversaw planting of trees in 6880ha of land. Villages created new forest blocks where additional trees were planted by the community.
Because Vijayapura is prone to drought, the forests run on a modern drip irrigation system using water harvested from recharged tanks hooked to solar panels for round-the-clock supply.
The programme has attracted millions of dollars of private investment as well as interest from other Indian states.
"We want to learn from this and expand planting in our state," said Sanjay Gherde, a forest official from the western state of Maharashtra, who travelled to Vijayapura for training.
Schools, universities, and offices have joined the mission to plant and conserve more trees.
People now give one another trees at weddings, birthdays and cultural events.
A marathon organised to encourage planting of trees has become a hit with younger residents, who routinely use the forests for cycling.
Some locals have taken it upon themselves to create their own mini-forests using saplings given out by the Government.
Nanasaheb Patil, 71, a retired government official who planted thousands of trees on a hill, recalled towering date palm trees in the area 60 years ago. The trees were lost to years of subsequent droughts and a famine that struck the region in 1972.