The water level in the Caspian Lake is currently below the lowest level on record, and according to the Baltic High System, the average is less than 29 meters. The mentioned data was published by the Volga-Caspian Branch of the Caspian Fisheries Research Institute (КаспНИРХ) [14] [21].

The study uses the terminology pair “Caspian Lake/Caspian Sea” according to its physico-geographical characteristics as the world’s largest closed endorheic reservoir. From a legal point of view, according to the Convention on the Legal Status of the Caspian Sea (2018), the term “sea” is used, but from a hydrological and water balance point of view, “lake” is correct. When discussing hydrological processes in this article, preference is given to the term “lake” and the term “sea” in the context of historically shaped geopolitical and transportation practices.

The results of chronological data analysis and prospective modeling show that the steady decline in the level of the Caspian Sea during the period 1990-2045 may be about 4.7 meters, and may reach about 18 meters by 2100. A steady decline in the level of the Caspian Sea may occur until 2100. This trend indicates the formation of a deep hydrogeodynamic and environmental crisis, which is already beginning to significantly affect the economic structure of the region, the stability of ecosystems and geopolitical processes.

If the current pace of development of events is maintained, the realization of the so-called “Aral scenario” for the Caspian Sea is becoming more and more probable. According to the available forecasts, in the medium and long term, existing transport links and coastal infrastructure may lose their functional efficiency.  Such a development of events can radically change the economic, ecological and geopolitical balance not only of the Caspian Basin, but also of the entire Caucasus region. [21]:

The comparative analysis of the “Aral scenario” in relation to the Caspian Sea requires caution. In contrast to the Aral Sea, where the main reason for drying was the almost complete cessation of river flow for irrigation [36], in the case of the Caspian Sea, climate change (increased evaporation) and anthropogenic losses play a dominant role. However, the hydrodynamic similarity (both bodies of water are endorheic, shallow in the northern part) makes the “Aral scenario” a heuristically useful but not a literal analogy.

Introduction:

The relevance of the study is due to the continuous unprecedented fall in the level of the Caspian Lake, which poses threats not only to ecosystems, but also to the economic and transport infrastructure of the Caspian basin states.: Despite the existence of separate hydrological and environmental publications, comprehensive interdisciplinary studies combining hydrodynamic analysis with geopolitical and geoeconomic forecasting remain limited.

The object of the study is the hydrological regime and the modern dynamics of the water level in the Caspian Lake as a factor of regional changes.

The subject of the research is the ecological, economic and geopolitical consequences of the water level decline for the countries of the Caspian basin and neighboring states (including Armenia).

Study the aim is to identify and coordinate the main consequences of a steady decline in the level of the Caspian Lake, as well as to assess the possible transformation of regional transport corridors and geopolitical balance.

Research objectives․To analyze the modern dynamics of the water level and the quantitative parameters of the water balance of the Caspian Lake.

Assess the contribution of natural and anthropogenic factors (including oil extraction) to the recycling process.

Consider scenario forecasts (“optimistic”, “negative”, “Aral”) and their possible ecological consequences.

Determine the impact of lowering water levels on shipping, port infrastructure and the Trans-Caspian International Transport Corridor (Middle Corridor).

To analyze the indirect consequences for countries without direct access to the Caspian Sea (for example, Armenia) in the context of CSTO and EAEU membership.

The methodological basis of the research. The study was carried out within the framework of an interdisciplinary approach, which combines the methods of hydrological analysis (water balance calculation, hydrometeorological services data processing), scenario forecasting (on the basis of three scenarios developed by KMG Kashagan B.V.), geo-economic analysis (assessing cargo flows and transit potential) and political-geographical description.

The application of the water balance formula is of a computational-illustrative nature, based on the data of open sources and official reports (World Bank, UNEP, КаспНИРХ, Kazhydromet, Azerkosmos). The limitations of the method are related to the lack of complete open-access data on underground inflow, man-made water losses during oil extraction, and water intake, which is reflected in the relevant assumptions of the calculation.

Environmental factor. Since 2006, the water level of the Caspian Lake has shown a steady decreasing trend, reaching critical indicators in 2025. The State Oil Company of Azerbaijan (SOCAR) has already alerted about this situation, noting that the drop in sea level has a negative impact on the normal operation of the company’s production platforms. [5]:

The mentioned circumstance most likely conditions the projects implemented by SOCAR together with the TotalEnergies company, which envisages the drilling of super-deep wells for the purpose of assimilation of new hydrocarbon reserves, despite the existing serious environmental and hydrological problems of the Caspian Sea [6].

At the same time, the international analytical agency Fitch Solutions questioned the possibility of exporting 20 billion cubic meters of natural gas from Azerbaijan to Europe per year until 2027. This circumstance also indicates the poor ecological, hydrological and resource situation of the Caspian Sea. [7][8][9].

According to a special report by the World Bank՝ The water level in the Caspian Sea is currently in a critical state and continues to decrease, leading to aggravating problems with the operation of infrastructure, navigation and the efficient operation of ships in ports.: The report specifically emphasizes that a number of courts are no longer able to fully utilize their technical capabilities, which turns this phenomenon into an important geopolitical factor [11].

Caspian Lake is the world’s largest closed endorheic basin (which has no flow to the ocean). Its hydrological regime is mainly determined by river inflow, atmospheric precipitation, evaporation, as well as anthropogenic “hidden” water losses related to technological water use in the process of oil extraction.

The formula of the water balance (hydrological regime) of the basin can be presented in the following form:

ΔV = (Qrivers P Gunderground) – (E Woil Way)

որտեղ՝

ΔV – the change in water volume (related to the change in level);

Rivers – river inflow.

P – atmospheric precipitation (atmospheric inflow).

Gunderground – underground inflow (if considered).

E – evaporation.

Oil – technological water use during oil extraction (seawater injection into wells).

Other – other anthropogenic losses of water (water, technical use, etc.).

On the hydrological regime of the reservoir, bApart from natural factors, the oil and gas industry is also affected: The oil extraction process uses the water injection method (water injection), which is used to maintain reservoir pressure in oil wells and increase extraction efficiency [23] [24] [25].

As part of this process, seawater is taken from the water body and injected into wells, as a result of which it effectively ceases to participate in the natural water cycle of the Caspian Lake and is considered an anthropogenic loss of water resources [23] [24] [25] .

According to estimates, in the case of daily oil production of 1.1-1.3 million barrels in the Caspian Sea, the volume of water injection reaches about 200,000 tons, which leads to anthropogenic “hidden” loss of about 1.4 million tons of water in a week [26] [27] [31]. This process has a significant impact on the water balance of the basin [26] [31].

A nearly 1°C rise in sea surface temperatures over the past 15 years has led to increased evaporation and disrupted biological processes. Reduced water volume and increased salinity have negatively affected phytoplankton life and reproduction, which in turn has led to a decline in fish stocks.:[35] The average rate of evaporation from the sea surface is approximately 1,000–1,400 mm per year (i.e., approximately 1.0–1.4 m of water per year), which is equivalent to approximately 371 km³ of water per year.[29][30] However, this figure is somewhat offset by precipitation.

The main source of water supply to the Caspian Sea is the Volga River. Volga, Terek, Sulak and Samur rivers flow into the lake from the territory of Russia. The annual flow of the Volga River accounts for about 80% of the total surface tributary to the Caspian Lake [22].

According to scientific reviews, the total annual inflow of river water flowing into the lake is formed by more than 130 rivers, the total annual flow of which is about 300 cubic kilometers of water. This indicator reflects the total amount of net river inflow.

The annual amount of atmospheric precipitation on the surface of the sea is usually estimated at about 200 mm per year. If we consider the surface of the Caspian Sea equal to about 371,000 km², the volume of atmospheric inflow can be expressed as follows:

P ≈ 0.2 m × 371 000 km² ≈ 74 km³/year.

By combining the above information about total water losses from the sea, the following water balance equation can be formulated:

ΔV = (Qr P) – (E Woil)

ΔV = (300 77) – (371 328.5) = -322.5 km³/year

Thus, the annual water loss is approximately 320 km³.

The presented calculation does not take into account the Wproch component, which includes water withdrawals from the Caspian Sea, technical water use, water withdrawals for industrial purposes and other anthropogenic losses. Although this factor may represent a significant volume, it was not included in the balance formula because there are no available and comparable concrete quantitative estimates in open sources or official publications.

Major sea surface drivers include climate change, which leads to changes in precipitation patterns and increases in temperature. The anthropogenic factor is also of significant importance: the intensification of water use, oil extraction and other types of water use, as well as the significant increase in evaporation from the sea surface under the conditions of rising temperatures.

In addition, Held on November 26, 2024 in the city of Atyrau (Kazakhstan). «Caspian Technical Conference» according to the scores presented in the panel session՝ in the case of the most unfavorable scenario of water level change, the Caspian Lake may be divided into two separate basins.  Such a development of events will have profound ecological, economic and geopolitical consequences for the entire region [1] [2].

Agreed «KMG Kashagan B. V.» according to the results of research carried out by the company, the dynamics of the Caspian Sea level change can develop in three main scenarios [3][4].

Unfavorable (negative) scenario– Within the framework of this scenario, the tendency of the water level in the Caspian Lake to decrease will continue. Currently, the average level has already reached the minus 29.8 m mark, which is the lowest level recorded in the last two decades. The average annual drop in level is estimated to be about 20 centimeters.

Optimistic scenario– This scenario assumes a stabilization of the water level and a possible slight increase in the long term. However, according to expert estimates, this scenario is the least likely to happen among the considered options.

Aralyang (worst) scenario– The most unfavorable and at the same time the most likely scenario assumes the division of the Caspian Sea into two separate water basins, on the analogy of the Aral Sea, which is currently represented by the North Aral (Kazakhstan) and the South Aral (Uzbekistan). If this scenario is implemented, the Caspian Lake can be divided into two main parts: Northern and M:the bottom–South.

In the case of any of the mentioned scenarios, serious environmental and geopolitical problems will inevitably arise in the Caspian region, as well as large-scale transformations that will affect the economic, energy, transportation and regional security systems.

According to expert estimates, the border between the two potential water basins may pass along the so-called “Caspian saddle”, which is a system of underwater ridges that extends between the Volga River delta (Astrakhan region) and the Prorva deposit in the Atyrau region of Kazakhstan.

This circumstance makes the North Caspian Sea relatively less vulnerable to drying processes. However, so called «Aral scenario» in case of implementation, the deformation of the coastline can become significant, as a result «Caspian saddle» can emerge from the water and become a narrow strip of land that physically separates the watershed.

One of the already visible manifestations of the mentioned processes is the situation prevailing in the Atyrau region of Kazakhstan, where a state of emergency is announced due to a sharp decrease in the water level in certain parts of the sea, as well as in the Kigach and Sharon rivers [15] [16]:

As of September 2025, measurements by the Kazhydromet service showed a continuous decline in the level of the Caspian Sea. According to confirmed data, the average sea level in the coastal regions of the country was minus 29.31 m (according to the Baltic height system). It is noteworthy that in the northeastern part it was minus 29.15 m, and in the eastern part – minus 29.46 m. ​​Compared to the same period last year, the decrease is estimated to be about 17-20 centimeters [14]. The long-term trend is even more pronounced.

According to the analysis of the Russian State Oceanographic Institute and “Kazhydromet” service, in the 18-year period of 2006-2024, the surface of the Caspian Sea has decreased by 36,6 thousand square kilometers[33]. During the same period, the water level in the Kazakhstan region decreased by 2.13 m in total (from minus 27.07 m to an average of minus 29.20 m) [15]. These dynamics lead to rapid retreat of the coastline, especially in the northeastern shallow part of the sea. In separate parts of the territory of Kazakhstan, the coastline has receded to 30-35 kilometers [15][16].

According to the assessment of the Azerbaijani space agency (“Azercosmos”), during the last 20-25 years, in the northern part of the sea, where the depth does not exceed 5 meters, the reduction of the water area took place over a distance of more than 70 kilometers [34]. This process directly threatens ecosystems, fish resources, shipping and coastal infrastructure, which requires coordinated and immediate cooperation among all countries of the Caspian Basin.

The lowering of the level of the Caspian Sea is most pronounced in the Kazakh part, but has serious consequences for all states of the region. According to the actual data, the process of shallowing is already causing significant economic consequences, including the complexity of the operation of the oil extraction infrastructure, the deterioration of shipping conditions, and the increased need for regular dredging and cleaning of port facilities.

In terms of lowering the sea level in the coastal zone of Azerbaijan, the area of ​​Kyzylagaj Bay is the most vulnerable, where the area of ​​dry areas already exceeds 700 square kilometers.

«Azercosmos» according to the monitoring data of the space agency, if this trend is maintained, the ecosystems and geographical landscapes of the coastal regions will be under threat, in particular, the islands of Gum and Piralahi, whose possible connection with the mainland (the formation of a peninsula) is considered a real risk.

In February 2025, within the framework of the third economic conference of the Caspian region in Tehran, key attention was paid to the prospects for the development of regional transport links. In particular, the Trans-Caspian international transport corridor was discussed. «North-South» international transport corridor as well «Caspian Lake-Persian Gulf» the transport route [12].

The issue of sustainable lowering of the water level in the Caspian Lake and the related environmental and economic challenges occupied a central place in the agenda of the conference. In his speech, the Prime Minister of Azerbaijan emphasized the seriousness of the problem and the need to form a unified interstate approach to preserve the ecosystem and solve the problem [13]. M:the concerns are also confirmed by the statistical data of Azerbaijan. According to the statement of the head of the State Water Resources Agency, over the past 45 years, fresh water reserves in the country have decreased by about 25 percent, which is partly due to the drop of the Caspian Sea level by about two meters.

Geopolitical and economic dynamics. The convergence of the Caspian Sea in the medium and long term may lead to a significant weakening or termination of regular sea connections and the existing coastal border zones of the Caspian countries. The Caspian Lake is a closed reservoir, and its sea communications are only functional if there is sufficient depth, navigable roads, a stable coastline and technical access to ports.

Caspian countries that lose de facto “sea borders” in the sense of maritime connectivity;

 Kazakhstan-Azerbaijan

The most vulnerable is the Kazakhstan-Azerbaijan connection. Kazakhstan’s Aktau/Kurik ports connect the country with Azerbaijan (Baku/Alyat). This is the main part of the Trans-Caspian International Transport Corridor (Middle Corridor). In the event of a narrowing, Kazakhstan effectively loses a quick sea outlet to Azerbaijan, and Azerbaijan loses a sea bridge with Central Asia.  As a result, the corridor becomes more dependent on Russia or Iran, which changes the balance of economic power in the region.

Turkmenistan-Azerbaijan

Turkmenbash port connects Turkmenistan with Azerbaijan. This is an important destination for cargo transportation, gas projects and logistics. During the blockade, Turkmenistan loses a part of the Western exit, and Azerbaijan «of the energy bridge» potential sector.

Russia-Iran

This connection is of a strategic nature. The Caspian Lake is a zone of Russian-Iranian cooperation. In case of shallowing, some routes may become difficult, especially in shallow areas, which increases the load on Russian ports. and: on shipping (in particular, in the direction of Astrakhan/Dagestan).

Iran-Azerbaijan (and Turkmenistan)

Iran controls the southern part of the Caspian Sea, which is relatively deep, but if it becomes heavy, there will be problems with sea communications with Azerbaijan, Turkmenistan, Kazakhstan and Russia.

Changing coastlines can affect the role of local ports; Iran may try to strengthen its position as «alternative land corridor»:

Economic dynamics

In the conditions of the weakening of the Caspian sea connections, the importance of the land routes of Russia, as well as the routes passing through the territory of Armenia and Iran, is increasing. This changes logistics flows and redistributes strategic advantages in the region.

Azerbaijan as «transit hub» diminishing role. Sea transportation in the structure of Azerbaijan’s foreign trade generally makes up a relatively small share (up to 5%), but if we take into account important transit cargo flows, the share of transportation through the Caspian Sea increases to 23-24%, that is, it means the key role of the sea in the transit model [32].

In monetary terms, this is approximately 6.5-6.8 billion US dollars per year. According to statistical data, the cargo turnover of Aktau and Kurik ports in 2023-2024 shows multifaceted dynamics.  At the same time, the International Caspian Transport Bureau estimates that a 1-meter drop in sea level increases dredging costs by an average of 15-20% per year. In terms of money, it can be an additional 30-40 million dollars per year for the port complex of Kazakhstan.

Weakening of the midline

The Middle Corridor connects China-Kazakhstan-Caspian-Azerbaijan-Georgia-Turkey-EU. The crossing of the Caspian Sea may result in the countries of the Caspian basin effectively losing their maritime borders and direct water connections with each other and shifting transport flows to land routes, increasing the influence of some countries and weakening the economic role of others.:

If Kazakhstan-Azerbaijan-Georgia-Turkey maritime communication weakens, the effectiveness of the system that limited Russia’s monopoly in the region will decrease. This means that Russia’s logistical and political role in the region may increase, while new opportunities open up for Armenia.

In the conditions of the problems related to the Caspian Lake, land routes through the territory of Iran become more significant. This gives Armenia the opportunity to turn its connection with Iran into a strategic logistics hub, develop the “North-South” concept and present itself as Iran. → Georgia → Black Sea land bridge. In other words, the weakening of the maritime corridor through the Caspian Sea can increase the strategic value of the route through the territory of Iran for Armenia.

In this context, in his speech at the UN General Assembly on September 25, 2025, the President of Azerbaijan, Ilham Aliyev, emphasized the following. “The Caspian Lake is rapidly shrinking, and the main reason for this is not climate change at all” [20]. This statement, regardless of its causal justification, testifies to the high political significance of the problem and the fact that the countries of the region evaluate it from different perspectives, which can complicate the development and implementation of a joint strategy for solving the problem.

Analysis of indirect consequences for Armenia (hypothetical scenario)

It should be emphasized that Armenia does not have a direct access to the Caspian Sea, so any conclusions about the impact of weighting on it are hypothetical and scenario-based, and not based on proven cause-and-effect relationships.

Hypothesis 1 (transportation)․ If lowering the level of the Caspian Lake leads to a significant reduction in the flow of cargo transportation through the middle corridor (Kazakhstan-Azerbaijan-Georgia), then part of the transit volumes can theoretically be redistributed to land routes. In this context, the Iran-Armenia-Georgia route can gain a relative advantage as a stable route to the Black Sea.

Hypothesis 2 (transit)․ With the completion of the construction of the “North-South” highway and the possible opening of regional communications (within the possible settlement of Armenian-Azerbaijani relations), the transit potential of Armenia may increase.

At the same time, it is important to consider that the process of convergence of the Caspian Sea itself, although not a direct driving force of political changes, is able to create indirect incentives for the revision of the transport logistics of the Caspian states. In particular, the countries of the Caspian Basin (especially Azerbaijan and Kazakhstan) may be pushed to diversify export channels, including, other things being equal, to more pragmatic consideration of overland alternatives.

If the economic pressure caused by the narrowing (additional costs of port infrastructure, reduced predictability of maritime transport) reaches a certain threshold, it may indirectly increase the interest of the parties in finding sustainable land corridors, including those that pass through the territory of Armenia.

It is important to emphasize that any transport initiative of Armenia (including the so-called TRIPP) stems from the need for full compliance with the obligations of the Republic of Armenia within the framework of the Eurasian Economic Union (EAEU) and the Collective Security Treaty Organization (CSTO).:

The charters and founding agreements of those organizations ratified by Armenia have direct binding force and define the foreign economic and foreign political context in which any regional cooperation is implemented. Thus, the Armenian transit potential is considered not as an alternative to Eurasian integration, but as a logical complement to it: a land bridge that connects EAEU countries through the territory of Armenia with Iran, then with the Persian Gulf, as well as with the Caspian Basin states.

Thus, the hydrological crisis in the Caspian Sea does not predetermine political decisions, but creates an additional economic context in which the benefits of unblocking regional communications (within Armenia’s existing alliance commitments) can be perceived as more weighty.: The degree to which this potential is realized remains largely dependent on political factors, and hydrological changes create an additional economic background, but do not act as an independent driving force.  [17][18][19].

Conclusion

The steady and accelerating decline of the water level in the Caspian Sea has ceased to be only an isolated ecological phenomenon. It has turned into a large-scale regional crisis that is inevitably reshaping the economic, transportation and geopolitical landscape of the South Caucasus and Central Asia.

Existing scenario projections (including the “Aral scenario”) indicate the possibility, but not the inevitability, of a critical transformation of the watershed, in which coastal infrastructure will lose its functionality, and key transit corridors, especially the Middle Corridor, will face serious operational difficulties.

The most significant economic and geopolitical consequence may be the weakening of the Trans-Caspian International Transport Corridor (Middle Corridor), while simultaneously increasing the relative value of overland routes through the territory of Iran and the South Caucasus. In this context, a new geometry of transit communications is needed.

The risk of disruption to sea routes, the significant increase in costs of port operations due to shoaling, and the general unpredictability of the route increase the strategic value of sustainable land transport links. Unlike unstable waterways, land routes through the territory of Armenia can ensure stable operation of transport flows.

The analysis shows that the lowering of the level of the Caspian Sea, being a factor complicating regional stability, creates new challenges, but also opportunities. Being a landlocked country, Armenia can form an active and proactive policy that will match the national security strategy and promote economic development.

DAVIT MATEVOSIAN

vpoanalytics.com

Translation by Zhanna Avetisyan

Used literature

1. Caspian annual technical conference

2. Climate Information Portal of Central Asia (Central Asia Climate information Portal)

3. “Furnishing of Kashagan mine facilities. Marine complex. Repair deepening works” project

4. KMG Kashagan B.V. (KMG Kashagan B.V.)

5. “The lowering of the level of the Caspian Sea hinders the normal operation of the company’s production platforms” 

6.  TotalEnergiesin Azerbaijan

7. Fitch SolutionsFitch Solutions Casts Doubt on Azerbaijan’s 20 bcm Gas Export Target to Europe by 2027

8. Natural Gas World

9. oilprice.com 

10. eurasianet.org 

11. World Bank “Economic North of the Caspian Sea. challenges and opportunities” (World bank “The Caspian Sea’s Shallow North. Challenges and Opportunities»)

12. Ministry of Foreign Affairs of the Russian Federation ministry 

13. azertag.az

14. tass.ru

15. Carnegie Endowment

16. en.tengrinews.kz

17. azertag.az

18. The Diplomat – “Receding Waters, Rising Challenges: Navigating the Caspian Sea’s Geopolitical Moment”

19. Caspian – Alpine Society – “The Caspian Sea: Economic and Geopolitical Consequences of Declining Water Levels”

20. report.az/en

21. “Climate change in the Caspian Sea region” international scientific conference materials

22. State Oceanographic Institute 

23. Popular Mechanics, March 1933 – on the invention of water injection for oil extraction article:

24. Mechanisms of biological clogging of materials in saturated soils and aquifers and ecological impact (Environmental Impact and Mechanisms of the Biological Clogging of Saturated Soils and Aquifer Materials)

25. Water injection (oil extraction)oil production))

26. Caspian offshore fields have collectively produced more than 1 million barrels per day in recent years, according to the EIA Regional Energy to hint.

27. Kashagan the mine produced ~378,500 barrels per day in 2024.

28. caspianpost.com

29. European Geological Society (European Geosciences Union)

30. United Nations Environment Program (UN environment program)

31. Open Data Center of Iran (Iran Open Data Center)

32. Cargo transportation by transport corridors in 2024 (Cargo transportation by transport corridors in 2024) st1yle=”box-sizing:border-box;margin-top:0px;margin-bottom:1rem”>33. Kosolapov A.E., Matishov G.G. Modern changes in the level of the Caspian Sea. causes and consequences // RGA bulletin. Geographical series. – 2021. – № 4. – Page 12-28.

34. Lemeshko E.M., Kasumov A.B. The transformation of the North Caspian coast under the influence of climatic and anthropogenic factors // Geography and natural resources. – 2023. – H. 44, No. 2. – Pages 56–64.

35. Ivanov V.P., Komarova N.V. Hydro-ecological problems of the Caspian basin. – Astrakhan. Publishing house of KaspNIRKH, 2020. – 312 pages.

36. Micklin P. Aral Sea disaster. lessons for Caspian // Geography, Environment, Sustainability. – 2019. – Vol. 12, no. 3. – P. 6–21

—