On a quiet but tense corner of Russia’s border, its neighbors are gaining on it

• Russia's neighbors on the Caspian Sea have been building up their naval capabilities.
• Russia remains the dominant military in the region, but that advantage is diminishing.
• The countries there have taken steps to manage disputes, but future points of tension are visible.

Thirty years ago, Russia's supremacy in the Caspian Sea was unquestioned. Even with the independence of new countries with their own navies in the early 1990s, Russia and its Caspian Flotilla had little to fear.

But as the 21st century enters its third decade, the Caspian Sea might not be a Russian-dominated lake for much longer.

In early October, Russia's Caspian Flotilla conducted drills in the sea, firing long-range Kalibr cruise missiles at an island off its coast. Only days later, Azerbaijani navy ships conducted three days of drills in the sea involving special-operations forces and patrol boats.

Russia retains a military advantage with its forces in the Caspian region, but the competing drills last month are a reminder that its neighbors are building up their own naval capabilities.

More players, more ships

Despite being isolated, the Caspian Sea has always been important. It has some of the world's largest offshore oil fields sitting on an estimated 48 billion barrels of oil.

Many of the largest oil fields were discovered in the 1990s and early 2000s, when the exact borders of the Caspian states were not clearly defined.

As a result, there were a number of disputes between the five Caspian littoral states - Azerbaijan, Turkmenistan, Kazakhstan, Iran, and Russia - over drilling and exploration rights. In 2001, for instance, Iran and Azerbaijan came close to open conflict because of a dispute over the Alov-Araz-Sharq oil field.

The strength of Russia's Caspian Flotilla helped it to avoid serious disputes. It also enabled Russia to exert its influence in territorial disputes between other littoral states.

Russia has continued to develop that flotilla as well. In October 2015, it demonstrated a significant new capability when some of its ships launched 26 Kalibr cruise missiles at 11 targets in Syria - a distance of about 1,000 miles. They launched even more missiles a month later.

Other Caspian Sea states have largely operated in the shadow of Russia's Caspian Flotilla, but in recent years they have begun to build up their navies to more modern standards.

Azerbaijan, with revenues from its own large oil reserves, has grown its navy and coast guard fleets to a combined force of over 30 ships. Most of them are patrol vessels, but some are relatively modern and advanced ships built by Israeli and Turkish firms.

Turkmenistan has also taken advantage of its commercial and cultural ties to Turkey and purchased a number of Turkish-made vessels. It has 10 Serhet-class patrol boats (based on the Turkish Tuzla-class) and commissioned its first Turkmen-class corvette in August.

Iran has historically had a limited presence in the Caspian. The waters it controls are among the deepest, averaging 3,360 feet, which makes offshore oil drilling difficult. Moreover, Iran's navy has mostly focused on the Persian Gulf.

But Iran is also building up its Caspian fleet. In 2003, it completed its first modern Caspian vessel, the IRIS Paykan, a Sina-class fast-attack craft. In 2015, it commissioned the IRIS Damavand, the second frigate of the Mowj-class - Iran's most modern warships.

IRIS Damavand sank after an accident in 2018 and is being repaired, but Iran has continued its activity in the Caspian, including regular drills and exercises.

Kazakhstan, which inherited no naval vessels from the Soviet Union, has built a navy with about a dozen ships, including a domestically produced class of missile boats. Kazakhstan also conducts drills and exercises in its waters.

Still the strongest

While there is no doubt that other Caspian Sea navies are stronger than they were 30 years ago, Russia's Caspian Flotilla remains the dominant naval force there.

Most of Azerbaijan's, Iran's, Kazakhstan's, and Turkmenistan's naval ships are small vessels such as patrol boats, missile boats, or fast-attack craft. The Caspian Flotilla has many similar vessels, but it also has more large warships than anyone else, chief among them the two Gepard-class frigates and six Buyan-class corvettes.

Those ships are smaller than the destroyers and cruisers of the Russian navy's other fleets, but, as demonstrated by the 2015 Syria strikes, they carry similar armaments, which are far more capable than the weaponry of neighboring navies.

"The Russians equip these small ships with long-range land-attack and anti-ship missile systems, and they really punch above their weight and size," Jeffrey Edmonds, a research scientist and Russia expert at the CNA think tank, told Insider.

Moreover, the Caspian Flotilla is part of Russia's powerful Southern Military District, one of the largest and most important military forces in the Russian military. As such, the Caspian Flotilla's combat power has to be evaluated alongside other assets in the district, such as aircraft and coastal defenses.

"You shouldn't view the Russian Navy broadly or something like Caspian Fleet separate from the rest of the Russian military," Edmonds said. "If there was a conflict in the Caspian Sea, you would have the full might of the Russian military in the region."

Additionally, the Caspian Flotilla could be reinforced by ships from Russia's Black Sea Fleet via the Volga-Don Canal, or even by the Baltic Fleet through the much longer Volga-Baltic Waterway if need be.

"The Russian military looks at the total correlation of forces." Edmonds said. "They'll calibrate their military capabilities in the region to match or overmatch any potential competitors."

As the naval buildup continues, so do efforts to manage it. In 2018, the five Caspian states signed the Convention on the Legal Status of the Caspian Sea.

Its signatories agreed to a 15-nautical-mile limit on territorial waters and to freedom of navigation outside those waters. The signatories also agreed on a principle of "a stable balance of armaments … within the limits of reasonable sufficiency."

The convention also forbids outside countries from establishing a military presence in the Caspian Sea.

But future points of tension are already visible. Russia and Iran are increasingly worried about Turkey's military buildup and growing influence in Azerbaijan and Turkmenistan. China's influence in the region is also growing.

Naval activity in the Caspian will likely increase as new oil fields are discovered and the region's navies grow. Russia's dominance is assured for now, but with more players, it may one day have to compete.