Mudflows in Almaty: Protective Measures and Escaping the Danger

Almaty, nestled at the foot of the mountains, faces the perennial threat of devastating mudflows triggered by increased glacier melting and heavy rainfall. These torrents of muddy water, rocks, and debris wreak havoc on any city situated in mountainous regions, and Almaty has witnessed its fair share of such events throughout history.

Let's delve into some of the most significant mudflow incidents that have battered Almaty.

1841. A mudflow descended along the Malaya and Bolshaya Almatinka rivers, with scant historical records about the catastrophe.

1887 (Verny Catastrophe). An earthquake of magnitude 9-10 unleashed a destructive mudflow, reducing numerous structures to rubble and claiming lives.

July 1921. Heavy rains caused numerous rivers, including Malaya and Bolshaya Almatinka, Issyk, and Talgar, to overflow their banks, leading to widespread devastation. Witness accounts describe the horror of falling stones, uprooted trees, and building fragments. In mere hours, the mudflow nearly leveled the city.

1963. The rupture of the moraine-glacial lake Zharsai sent a colossal 7-meter high torrent of water downstream, obliterating settlements near Lake Issyk. This event prompted the construction of the 150-meter Medeu dam to safeguard the city.

July 1973. Another mudflow catastrophe resulted from the outburst of the Tuyuksu moraine lake due to heavy snow and rain. The mudflow raced at speeds of 10 to 12 m/s, reaching heights of up to 15 meters, and filling nearly 70% of the mudflow storage in just three hours. This prompted the government to raise the Medeu dam's height.

August 1977. A moraine lake near the Kumbelsu River burst, releasing mud, water, and massive boulders for nearly a month, causing destruction with ramparts reaching 12 meters in height.

2014. A mudflow targeted the town of Talgar, located 30 km from Almaty, damaging infrastructure but fortunately causing no casualties, as the city's mudflow dam held up against the force of the water.

The key factors contributing to mudflows in Almaty are moraine-glacial lakes, earthquakes, and heavy rainfall. City authorities are actively implementing measures to protect Almaty, including the construction of dams and other mudflow prevention structures.

Mudflow Protection Dams in Almaty

• The renowned Medeu dam, whose height, post-reconstruction in the 1970s, reaches an imposing 150 meters. Notably, visitors can ascend this dam by traversing the so-called Health Ladder, an ascent consisting of 842 steps leading to the top.
• The Mynzhylky dam, which, since 1958, has been considered inadequate for containing large water volumes. The journey to this location takes slightly over an hour by car.
• Situated 18 kilometers from Almaty, a dam on the Karagaily River is reachable by buses #14 and 39.
• A 40-meter-high, 422-meter-long dam on the Bolshaya Almatinka River, constructed in the 1980s. The majority of this barricade comprises a solid wall of boulders and pebbles, reinforced by a steadfast concrete wall. The remaining 140 meters of the dam serve as a reservoir designed to release excess water and debris.
• Three new mudflow protection dams are under construction: Ayusai dam, a dam on the Aksai River, and Chukurbulak dam in Khorgos, aimed at safeguarding the city, its people, and strategic facilities from potent mudflows.

In addition to dam construction, Kazselezashchita continually enhances its mudflow hazard monitoring system, employing cameras and sensors to predict mudflows and warn residents via SMS in case of danger.

How to escape a mudflow?

Escaping a mudflow in the mountains can be challenging, so careful planning and vigilance are essential.

• Check weather forecasts from Kazhydromet or Kazselezashchita before venturing into the mountains.
• Avoid mountain excursions immediately after heavy rainfall.
• Never camp near riverbanks; if the river suddenly becomes turbulent or the current accelerates, move to higher ground.
• Be cautious of cracks in the ground or asphalt, which could indicate an impending mudflow.
• If a mudflow approaches, move sideways, not against it, and do not hesitate.
• Designate a lookout who can warn of danger.
• Keep an ear out for noise and rising mud clouds, similar to fog, as signs of an approaching mudflow.
• Domestic animals, particularly sheep, can sense the impending threat and often react before humans. Pay attention to their behavior.