The shrinking of the Caspian Sea is not a new topic in the CIS region by a long way, but alarm bells have been ringing that much louder in recent years. The issue is growing especially prevalent in Kazakhstan, where an initiative known as “Save the Caspian Sea” is beginning to take shape, led by Vadim Nee, an environmental lawyer and chairperson of the Socio-Ecological Fund. 

Nee recently sued the Kazakh government, or more specifically the Ministry of Energy, over its unwillingness to share the details of two production sharing agreements and one concession agreement relating to Kazakhstan’s three largest oil fields, Karachaganak, Kashagan and Tengiz. Nee is specifically seeking the environmental protection clauses of the agreements, as Kazakh citizens have the legal right to request access to such information, he told bne IntelliNews in an interview.

The three fields, located on the Caspian Sea and operated by Western-led consortia of firms, account for the vast majority of Kazakhstan oil output. The country’s economy, albeit undergoing a diversification drive, still relies heavily on oil exports.

At present, Nee’s initiative is largely Kazakhstan-focused, though he realises that, in the long term, it would have to involve other Caspian littoral states. The other such states are Azerbaijan, Russia, Turkmenistan and Iran.

“We are hoping that this initiative would at least represent a necessary small step to make the situation more transparent at least on the scale of Kazakhstan,” Nee told bne IntelliNews. 

“We are trying to engage all the Caspian Sea countries in the dialogue,” Nee noted. “That’s why we are aiming to [eventually] engage with international transboundary cooperation as well.”

“Russia and Iran will be a big challenge for us and for the [Kazakh] government [to deal with on the question of Caspian Sea preservation],” he said. 

Indeed, Kazakhstan’s contribution to the shrinking of the Caspian may be relatively minor compared to that of Russia, from where the most relevant river flows into the Caspian originate. But it is a team effort that would require both nations to take action and responsibility.  

Who is killing the Caspian?

According to Kazakhstan’s Ministry of Ecology, the sea has lost more than 22,000 square kilometres (8,500 square miles) of surface area since 2006. More than half of that loss has occurred along Kazakhstan’s northern coastline, where the receding waterline has transformed former seabed into desert and stranded once-busy fishing ports.

The sea level currently stands at approximately 29 metres below global sea level, down from 28 metres a decade ago. Modelling by scientists at the University of Bremen indicates that the sea could fall by an additional eight to 30 metres by 2100 under medium- to high-emissions scenarios. Even under conservative projections, a loss of five to 10 metres is expected, which would erase more than 100,000 square kilometres from the Caspian’s surface area — equivalent to the size of Iceland.

The causes are twofold: rising regional temperatures are increasing evaporation, while river inflows are declining due to upstream water regulation and diversion. The Caspian Sea, unlike the oceans, is disconnected from the global hydrological system. It relies entirely on a delicate balance of river inflow and evaporation. As upstream consumption intensifies and climate patterns shift, the imbalance will continue to grow. 

More than 80% of the Caspian’s inflow comes from the Volga River, which is extensively dammed and regulated along its course in Russia. These structures, numbering in the dozens, hold back substantial volumes of water for hydropower, irrigation, and industrial use before the river reaches its delta in the Astrakhan region. Additional outflows through the Volga-Don Canal further reduce water available to the Caspian basin.

According to an article published by the Central Asia-Caucasus Institute (CACI) in 2023, “about 130 rivers flow into the Caspian Sea, however, in the ‘upstream’ of this lake about 80 percent of the water comes from the Volga River, the longest river in Europe, while the Ural and the other Russian rivers play an important secondary role.”

The article noted that “in recent years, Russia has built 40 dams on the Volga River and 18 more dams are under study and construction.” 

The second-largest contributor to the Caspian, the Ural River, with the exception of an abnormal flood event in 2023, has also been seeing a steady decline in regulated flow of water.

Interestingly, Nee believes that no major infrastructural changes harming the volume of water in the Caspian Sea have taken place in Russia in recent years.

“Russia has not constructed any new water reservoirs along the Volga river in recent years,” Nee told bne IntelliNews. “It is the change in precipitation that has led to less river flow from the Volga. But that’s a climate change issue.”

Regardless, many reports indicate otherwise. 

Water-intensive agriculture and industry in Russia has been further exacerbating the problem. Since 2022, Russia has expanded irrigation along the Volga basin in an effort to boost domestic grain production. The increased use of the Volga river for agricultural needs was driven by Russia's invasion of Ukraine and the resulting sanctions on Moscow, which led to trade disruptions and food import restrictions. Zaur Shiriyev, a nonresident scholar at the Carnegie Russia Eurasia Center, noted in an article published by Carnegie Endownment that these changes have intensified demand for water upstream, limiting outflow to the Caspian.

Moreover, Russia's military use of the Caspian Sea is also likely contributing to environmental damage, Shiriyev wrote. Russia’s Caspian Flotilla has launched missiles from the sea and used it as a transit route for naval assets (via the Volga-Don Canal) during the war​. This militarisation has raised environmental worries – for example, unspent rocket fuel from missiles potentially polluting the sea​. Caspian neighbours have been reluctant to confront Russia over these issues given the geopolitical climate.​

Elevated water temperatures and declining oxygen levels have been linked to mass die-off events that have hit the Caspian seal (Credit: Aboutaleb Nadri, Mehr News, cc-by-sa 4.0).

The ecological consequences are becoming increasingly visible. Since 2020, several mass mortality events involving the Caspian seal — a species endemic to the sea — have occurred along Kazakh and Russian shores. While investigations are ongoing, scientists have linked the die-offs to elevated water temperatures and declining oxygen levels. Rising salinity in shallow zones and a loss of habitat are also endangering fish spawning grounds and wetland biodiversity.

The falling water level is also reshaping coastal infrastructure. Kazakhstan’s port of Aktau has faced navigational challenges as the shoreline recedes, while Azerbaijan has reported difficulties maintaining full operability of the Baku port complex. Transport operators have begun dredging efforts to accommodate the increasingly shallow waters. As exposed seabed expands, there is growing concern over the spread of saline dust storms, which pose risks to health and agriculture inland.

“”Now that the Caspian Sea is becoming more shallow, they are trying to carry out dredging works at Aktau and Kuryk seaports,” Nee told bne IntelliNews. “The works are aimed at creating a canal along shallow parts of the Caspian Sea to make it easier for ships to pass from Aktau and Kuryk to Azerbaijan-controlled and Russia-controlled parts of the sea.”

“The dredging works would further contribute to the loss of water levels,” he added. 

The dredging works are related to the Trans-Caspian International Trade Route (TITR), also known as the Middle Corridor, which links China to Europe via the Caspian. The route’s importance began to grow following international sanctions on Russia over Moscow’s invasion of Ukraine. 

Belgian engineering group Jan De Nul has announced the completion of dredging works at the Kuryk port, PortNews reported on April 28. The project involved deepening the access channel and turning basin to accommodate large grain carriers and container feeder vessels, enabling safer navigation and improved cargo throughput as well as providing a critical alternative to traditional routes through Russia, the report said. 

While one would hope that the benefits of dredging works would far outweigh the inevitable contribution to water loss, the total water loss from all the factors combined is likely to harm the viability of the Middle Corridor. 

Shiriyev has suggested that falling water levels threaten the economic potential of the trade route​.

“Falling water levels impact every aspect of life, the maritime industry, and the region’s ecology, threatening the efficacy and economic potential of the Middle Corridor,” he wrote. 

Kazakhstan's Port Aktau is one of a number of ports that would be threatened by a further significant shallowing of the Caspian (Credit: Ashina, cc-by-sa 3.0).

Another minor contribution to the loss of the Caspian’s water levels in the coming years can be expected from the green hydrogen project meant to meet EU’s energy needs. 

“The EU project that envisages Kazakhstan producing green hydrogen for Europe’s energy needs will also lead to some loss of water volume in the Caspian, as hydrogen production will rely on water from the Caspian Sea,” Nee said, noting that the volume likely will not be too significant. Nevertheless, every inch matters as the Kazakh oil sector continues to rely on desalination and river diversion projects for operational water. 

Fate of Aral?

The long-term projections are stark. Researchers estimate that if the current trajectory continues, the Caspian’s northern section — which is shallowest — could dry up almost entirely within decades. A 2020 paper in Nature Communications Earth & Environment warns of wetlands of international importance transforming beyond recognition, along with the displacement of regional fisheries and the collapse of local economies.

Without substantial reductions in water extraction and a reassessment of industrial and agricultural water use in Russia and Kazakhstan, researchers say the shrinkage will continue — and may soon accelerate beyond recovery.

Kazakhstan has already seen the death of a large body of water, the Aral Sea, during the Soviet era and the comparisons between the Aral and the Caspian may seem to be a no-brainer. 

“We do not exactly expect the Aral Sea situation for the Caspian - the worst case scenario will probably see the Caspian segmented,” Nee assessed. 

It seems obvious that despite the worst case scenario not being as bad, Nee would prefer for the situation to stay as far away from the Aral experience it as possible.

Despite the Energy Ministry’s lack of response to Nee, the Kazakh parliament held a meeting to discuss the issue, where Nee took part in the hearing and commended the authorities for taking the problem seriously. But only time will tell whether such meetings are simply for show.