Taigan, Ukraine - The Taigan reservoir in central Crimea, once about 200 hectares (500 acres), has shrunk to a third of its former size; its shores a cobweb of cracked clay, its waterline metres below the nearest tree or bush even after several torrential rains in late November.

The image is opposite to how many Russians picture the Black Sea peninsula - a postcard paradise with palm-fringed beaches, azure waters and cheap local wine. After all, that's what the 2014 annexation was about - to regain the Soviet Riviera, the crown jewel of Russian czars, a naval and trade outpost once ruled by Roman emperors, Mongol khans and Ottoman sultans.

But the Massachusetts-sized inkblot of a peninsula mostly consists of arid steppes and mountains where shallow rivulets can sustain life only in their valleys and coastal areas. Agriculture here mostly depends on irrigation, and urban areas flourished only after the Soviets built two dozen reservoirs and a massive canal to divert water from the Dnieper, Ukraine's largest river.

In 2013, the North Crimean Canal drew 1.5 million cubic meters of water. It amounted to about 85 percent of Crimea's drinking and irrigation water. But shortly after the annexation, Ukrainian authorities shut the canal with a hastily-built dam.

The decision gained little attention amid the diplomatic cannonade that brought Moscow's ties with the West to Cold-War lows, and the ensuing separatist conflict in eastern Ukraine.

Yet, the water blockade will wrack Crimea's agriculture, economy and population of 2.3 million for years to come, according to environmentalists, irrigation experts and officials.

Chronic water shortages in Crimea seem inevitable - and may prompt resettlement of its residents to Russia, they warn.

"Hundreds of thousands will have to be relocated," Vladimir Garnachuk, political activist and head of Clean Coast Crimea, a non-profit monitor, told Al Jazeera . "Soon, we will see dust storms with salt that will move to the centre of Crimea."

Mikhail Romashchenko, a top Ukrainian water expert said that Crimea's own water sources would suffice for less than a half of its population.

"We're talking about one million people," Romashchenko, who is the director of Ukraine's Institute of Water and Melioration Issues, said in televised remarks in early November. "We consider Crimea a region with a catastrophically low water supply."

READ MORE: Life in the shadows of the Crimea blockade

'Humanitarian catastrophe'

From the very start of the water blockade, Ukraine knew it would bring about a humanitarian "catastrophe". Those were the words of Vasily Stashuk, Ukraine's top irrigation official at the time, who resisted the blocking of the canal.

The blockade has nearly eliminated agriculture in Crimea.

The amount of irrigated land fell almost 30-fold from almost 400,000 (10,000 acres) hectares, Crimea's pro-Russian agriculture minister, Andrey Ryumshin, was quoted by Radio Svoboda as saying in late November. Crimean pro-Russia authorities banned water-thirsty crops such as rice and soy, trying to introduce winter wheat, expand vineyards and orchids - or replace agriculture with sheep breeding, officials say.

"Agriculture has been cancelled," Valery Lyashevsky of Crimea's State Committee on Water told Al Jazeera.

Water accumulated in Crimea's reservoirs and once destined for irrigation is now being redirected to urban areas in the south and east, and most of the reservoirs have shrunk dramatically.

Pro-Russian authorities in Crimea reportedly pledged to complete a network of underground water pumps by 2020 - at the cost of almost $330m. But experts, such as Garnachuk, warn that the underground deposits depend on the shutdown canal and will run dry within years.

This summer, half of Crimea's 14 districts faced drinking water shortages, officials said in August. For several weeks, a town and several villages in eastern Crimea got their drinking water from trucked tanks, they said.

The "return" of Crimea propped up President Vladimir Putin's approval ratings to 88 percent. But water shortages may ruin his plans to turn Crimea into Russia's top tourist destination. Before the annexation, the peninsula received up to 6 million tourists annually, and Putin said the figure should rise to 14 million.

The discontent of locals is the last thing the Kremlin needs amid Western sanctions, a crippling economic crisis and Crimea's painful "transfer" to the Russian legislation. Pro-Russian officials said they cannot afford to divert water from mainland Russia across the narrow Kerch strait or build energy-hungry water desalination plants.

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Looming environmental disaster

The problem is aggravated by a major environmental hazard.

The northern Crimean town of Armyansk is home to the Crimea Titan, a major producer of titanium dioxide, chemical fertilisers, sodium and lithium that belongs to Ukrainian oligarch Dmitry Firtash, who has been investigated by the US FBI and is reportedly wanted in Spain for money laundering.

Although thousands of businesses and properties that belonged to the Ukrainian government and businessmen have been expropriated or strong-armed by pro-Russian authorities, Firtash retained the ownership, and his plant consumes 48,000 cubic metres (1,700,000 cubic feet) of water a day.

"They rapaciously pump water from underground sources," activist Garnachuk said of the plant's managers.

Firtash's press service did not comment to Al Jazeera on the allegations.

In several papers written on the drought, Garnachuk says that underground aquifers in northern Crimea are being filled with salty water from the Sivash, or the "Rotten Sea," a cluster of shallow, noisome lagoons that separates the peninsula from mainland Ukraine.

Pro-Russian Crimean officials and experts admit that parts of northern Crimea are already turning into salt marshes because the drought raises underground salts deposits to the surface.

Putin is adamant about Crimea being an "inalienable" part of Russia, and his Ukrainian counterpart, Petro Poroshenko, seems no less determined to use any means necessary to complicate Kremlin's plans on the annexed peninsula.

"Nobody is going to save Crimea," Garnachuk said. "Ukraine understands that water supply is a critical problem for Crimea, and they will maximally complicate irrigation, nobody is going to resume [the water flow to the North Crimean Canal]."