Facing unprecedented water shortages, T.N. Ravisankar is praying for rain — and soon.

Treating patients will “depend on God’s mercy” if water supplies in Chennai, India’s fourth-largest metropolis, aren’t replenished shortly, said Ravisankar, the chairman of Sudar hospitals. Piped water at his hospitals has dried up, and even the more expensive water trucks he now relies on may be unavailable soon in the state of Tamil Nadu.

“The cost escalation will have to be passed on to patients,” Ravisankar said. “If the situation continues, after a month we won’t be able to serve patients.”

Failed rains last year and delays in this year’s monsoon have left nearly half of India facing drought-like conditions, said the South Asia Drought Monitor. Tamil Nadu is trapped in a “severe dry” cycle with other states like Karnataka, Andhra Pradesh and Maharashtra. The capital, New Delhi, has recorded the worst monsoon delay in 45 years — with piped water available to less than a fifth of Delhi homes.

As the impact of climate change worsens, water is shaping up to be a serious economic risk in Asia’s third-largest economy. Desertification, land degradation and drought cost India about 2.54% of gross domestic product in 2014-15, the environment ministry said.

India has witnessed widespread droughts in four of the past five years, and the government forecasts that per head availability of water will fall by 35% next year from 2001 levels. Hospitals, which rely on water for sanitation and preventing infections, are suffering as the cost of water rises.

The administration of Prime Minister Narendra Modi, who promised a health care expansion ahead of his re-election in May, announced a water conservation awareness program on July 1. Yet it’s unclear if the measures will be enough to ensure a steady supply of clean water.

“Not many are informed about just how big the dangers are,” said Arivudai Nambi Appadurai, head of India adaptation strategy at the World Resources Institute, a Washington-based group. “The quality of water being bought even by homes in drought-struck areas has caused allergies, sending more patients to local hospitals in places like Chennai.”

Almost all of Chennai’s hospitals are now dependent on the more than 5,000 privately-owned tankers that ferry water around the city every day, said N. Nijalingam, president of the Tamil Nadu Private Water Tanker Lorry Owners’ Association. But it’s becoming tougher to source water, he said. “If the situation continues, after a month we won’t be able to supply water even to the people who can pay a huge sum for a tanker of water,” he said.

The price of a 12,000-liter water truck soared from 1,200 rupees ($17.50) in April to as high as 6,000 rupees since shortages began, the News Minute website reported. Smaller nursing homes and clinics in Chennai, a medical tourism hub, have been hit harder than larger hospitals that have more money, said Balaji Venu Gopal, a vascular surgeon in Chennai.

The water shortages risk further hurting the struggling state-run health system. India spends only around 1% of GDP on healthcare, and aims to increase it to 2.5% by 2025. By comparison, nations whose entire populations have access to health services spend as much as 6% of GDP on insurance and healthcare, according to the World Health Organization.

“The pressure on us rises every time there’s a drought,” said Ashok Thorat, chief medical officer at a state-run hospital in Beed, Maharashtra. “More people turn up at our government hospital because private clinics have to pay more to buy water and pass on costs to patients. We can arrange at least some free water from the municipal corporation, but even that has limits.”