The construction of the Medeo mudflow protection dam in the Medeo tract in the valley of the Malaya Almatinka River began in 1964 and was carried out using blasting operations. The first explosion (right bank) was carried out in 1966. The second explosion (left bank) was in 1967. The first stage rockfill dam, 107 meters high, formed a mudflow reservoir with a capacity of 6.2 million cubic meters and was put into operation in 1972. In 1973, the dam blocked a mudflow with a mass volume of 5.3 million cubic meters.
Creation of the Medeo dam. The first right bank explosion took place on October 21, 1966.
Medeo tract. Everything is ready to explode. The initial phase of the explosion. The apogee of the explosion. Rocky soil is laid in the body of the dam.
The mudflow occurred in the early evening of the weekend of July 15, 1973. At an altitude of 3500 meters above sea level, a breakthrough occurred in the natural dam of moraine lake No. 2 on the Tuyuksu glacier. The resulting mudflow destroyed a light dam in the Mynzhilki tract in a few seconds, swept past Chimbulak in a matter of minutes and demolished half of the Gorelnik tourist center. Unfortunately, most of the tourists were at that very site at that moment, and they all died.
The Gorelnik camp site was destroyed with such stones. 
Then scientists calculated that the strength of the 1973 flow was 4 times higher than the strength of the 1921 flow. Then a quarter of the entire city's buildings were destroyed, more than 500 people died.
Fragments of the anti-mudflow trap on Gorelnik (above the Medeo dam). 
A steel barrier, concreted into the walls of a narrow gorge, secured by ten steel ropes, each as thick as an arm, delayed the mudflow for just a few seconds. A shaft almost 30 meters high, having broken through a fifty-meter deep canyon here, rushed further - to the dam in Medeo.
Quickly breaking out from around the last turn, disintegrating along the foundation pit, it fell with all its weight onto the shield of Alma-Ata - the dam. The dam held. She obscured the city.
July 15, 1973, 6:15 p.m. The entrance of the first wave of mud-stone flow into the mudflow reservoir in the Medeo tract.
The mudflow hit the body of the dam and choked, filling the pit. 
The waters of moraine lakes brought almost 4 million cubic meters of mud and stone mass to the dam. Three hours later, a second mudflow came down from the mountains, raising the water level of the resulting lake even higher.
Mudflow Canyon. 
The next day, July 16, at 5:25 p.m., a post near the Sarysay River reported that there was a mudflow again. The same news was received at 21:10 from a post near the Chimbulak River. Mudflows from Sarysay and Chimbulak lasted a total of one and a half hours.
Having tamed the mudflow avalanche, the dam already held almost 5 million cubic meters of mudflow in its bowl.
Medeo tract. Mudflow lake, dam, high-altitude ice stadium “Medeo” (from left to right).
The dam withstood the first assault, but now the siege has begun. The mudflow clogged the drainage pipes. There was a real danger of overflowing the mudflow lake, which received up to 12 cubic meters of Almaty water every second.
Work on the dam began as early as 5 a.m. on July 16. It was necessary to use at least 12 powerful pumps and lay kilometers of pipelines. They began to install them immediately. At least 10 dredgers were needed, which were not available in Almaty at all; they were delivered by cargo planes from Moscow, Chelyabinsk and Orenburg, and on July 20 they began to work.
Mudflow lake behind the dam. 
An emergency government commission to combat mudflows was urgently formed and took emergency measures to carry out emergency work. Hundreds of dump trucks, bulldozers, excavators, and pipe-laying cranes were sent to the dam.
"Construction" headquarters. 
The army took on a lot of work (pontoon boats, construction battalion). The divers were civilians, from the Volga, there were also military men, from the Baltic, specialists in working in conditions of almost complete lack of visibility (plunging into the mudflow mass, a team of divers tried to break through to the blocked water intake of the dam).
Meeting with army commanders. 
They began to urgently bring in equipment and people to organize pumping of water from the mudflow reservoir. 
The cranes were pushed to the very edge, they stood on unreliable soil, but the people working on them were experienced.
Pumps on pontoons. 
It was necessary to install three strings of a pipeline with a diameter of 1420 mm and a kilometer in length, and the welding seam had to be perfect - there was no way to fix it during pumping. We selected the best welders throughout the headquarters, they welded day and night, and at night the construction site was illuminated by spotlights.
Main work platform (left side). 
Main work platform (right side). 
On July 18, water filtration began in the body of the dam; simply put, leaks formed. It was urgently necessary to pour concrete. But concrete cannot be placed on a wet surface, and even if it is placed, it must dry for a certain time. On July 19, they began to spray the oozing streams with the help of ventilation ducts, and immediately concrete the surface of the dam, using the same fans for drying - the work of the Promventilation trust played a big role here. In just one day, five kilometers of spiral-wound air ducts were manually installed.
Filtration - leaks in the dam (filmed in the evening, blurred). 
Every day the water in the reservoir rose, hiding in its depths the tops of the spruce trees growing along the slopes. By 00:30 on July 20, it reached its maximum level. There were less than 15 meters left to the top of the dam.
Work site. 
The pumps started working and water began to be discharged. 
When the pumps drove water through the pipes, the flow did not want to go down the bed prepared behind the dam. He began to destroy rocks, trying to rush into the ice stadium. And then Ugudey Akayev, Gennady Kupriyanov and Valery Gomonov made a “jewelry” explosion, which removed the threat from the sports complex facilities.
Discharge of water along the rocky slope of Mount Mokhnatki. 
One and a half kilometers above the dam, the builders of the Alma-Ata-promspetsstroy trust, in record time, built a water intake, laid a conduit capable of taking the raging Almaty River into the steel channel, and, bypassing the mudflow reservoir, directing it beyond the dam. At noon on August 2, the damming of the river began, and within a few hours its conquered waters flowed at great speed along the channel laid by the builders.
Pumping water from Malaya Almatinka. 
The fight against the consequences of the mudflow took place on both sides of the dam. It was still hot in the mountains, even near the glaciers. Every day they melted faster and faster, and thousands of streams rushed along the slopes, filling river beds to the brim. To prevent a new mudflow from the Tuyuksu moraine, a special team from helicopters dropped bombs onto the glaciers, creating a dense smoke screen from the scorching rays of the sun.
Completion of work. The mudflow brought a large amount of silt and mud; it was necessary to restore the volume of the mudflow storage facility. The soil was selected by excavators and removed. 
After the mudflow of 1973, it was decided to build up the dam. The completion of the second stage of construction in 1980 significantly increased the capacity of the mudflow storage facility to 12.6 million cubic meters, the height of the dam was increased to 150 m, its length along the crest was 530 m, and its width at the base was 800 meters.
"Medeo - days and nights of courage." Documentary film about the events of those days.
(Link to video if the embedded one doesn’t open: http://www.youtube.com/watch?v=1phOWYxMDBc)
Oraz Bisenov, one of the mudflow liquidators, head of the Glavalmaatastro department in 1973:
“When we were working on the dam, we didn’t think about fame or, as they say now, about PR - I generally kicked the film and television crews out of the construction site so that they wouldn’t interfere with their work, as a result of which I never got into the frame of the film that we We've just watched it, although this film is a valuable document on the history of Almaty - the city in which I spent my whole life building.
I was very proud then that we have such a city, which we protect from mudflows, such a republic and such a country - such a powerful centralized state that it can concentrate when someone is in trouble. I don’t know if this could happen now if this happens again?”
Website materials used:
Big Sel-1973: thirty-five years later
Walk along the Maloalmatinsky gorge.
"Nature's idle spy,
I love you, having forgotten everything around you,
Watch out for the swallowtail
Over the evening pond"
Afanasai Fet. "Swallows".
Trip to the Medeo dam from Almaty.
Dam in
rises immediately behind the high mountain. In 1966, to protect against mudflows, the Maloalmatinsky gorge was blocked by two unique directed explosions. A complex hydraulic structure rose to a height of 150 meters. A huge mudflow reservoir has been built on the southern side of the dam, and the river flows through a tunnel. The mudflow protection structure is located 15 kilometers from Almaty. Construction began in 1964 and was carried out using blasting. The first explosion took place in 1966, the second in 1967. The rockfill dam of the first stage (height 107 meters, body volume 5,000,000 cubic meters) formed a mudflow reservoir with a capacity of 6.2,000,000 cubic meters and was put into operation in 1972. In 1973, it detained a powerful catastrophic mudflow with a mass volume of 5.3,000,000 cubic meters, which significantly exceeded the capacity of the mudflow reservoir. The dam withstood the pressure of the mud-stone mass and flood waters, part of them was diverted using a system of siphons and sluices. After this mudflow, a decision was made to build the 2nd stage of the dam, which was completed in 1980 and significantly increased the capacity of the mudflow reservoir to 12.6 million cubic meters.The height of the dam above sea level is 1750 meters above sea level and was raised to 150 meters, the length along the crest is up to 530 meters, the width at the base is 800 meters. 
Medeo is a sports complex built in the Medeo mountain tract at an altitude of 1691 meters near Almaty.
At the moment, Medeo is the highest mountain complex in the world for winter sports with the largest area of an artificial ice field - 10.5 thousand square meters. m. The high mountains and the purest mountain water for filling the ice contribute to the achievement of high results in speed skating; over 200 world records have been set here at all distances among men and women. Suffice it to say that the best speed skaters in the world nicknamed the Almaty skating rink “the factory of records”
16 photos, total weight 3.8 megabytes
1. Construction of the sports complex began in the fall of 1949, the first official competitions took place on February 4, 1951. But the stadium with artificial ice was built only in 1972. Behind the skating rink you can see the anti-mudflow dam.2. After the collapse of the USSR, Medeo gradually fell into disrepair; competitions were not held for a long time. However, in 2003, a complete technical reconstruction of the high-mountain sports complex was carried out.
3. Discharge receiver (?) on the dam from the sides of the mudflow.
4. An ultra-modern cable car was built from Medeo to the Chimbulak ski resort with a length of 4.5 km. Using the new gondola line (made in Austria), the ascent to the ski slopes takes no more than 15 minutes.
5. The Medeo stadium and the Chimbulak ski resort underwent major refurbishment in preparation for the 2011 Asian Winter Games. During the reconstruction, most of the engineering and technical systems at the stadium were replaced. There is a new refrigeration station for cooling ice. The visualization system (electronic scoreboard and photo finish), lighting and sound system have undergone changes. A new multimedia scoreboard with an area of 200 m² from the Billboard Video company (USA) was installed, which allows displaying the results of sports games, broadcasting TV programs, thematic and advertising videos. The capacity of the spectator stands has been increased to 8,500 seats. The medical rehabilitation and press centers have been reconstructed, and the area in the hotel complex has been increased by 400 beds. A fitness center of 3400 sq.m. was built. m. From 2 to 3 thousand people can skate at the same time on the ice arena of the skating rink.
6. The concept of the cable car was developed in such a way that the gondola road from Medeo to Shymbulak, as well as four cableways on Shymbulak itself, formed one whole, allowing skiers and tourists to be on the the highest point of the mountain resort - the Small Talgar Pass.
7. The base of the skating rink’s ice field, 2.3 meters thick, consists of more than 20 types of building materials. The base structure consists of reinforced concrete plates in which 170 km of cooling pipes are distributed. The artificial ice freezing system has no analogues throughout the world and allows you to maintain the ice surface of the skating rink for 8 months of the year.
8. The line can operate up to 115 eight-seater cabins (70 cabins were used during the 2011 Asian Games), the speed is 5 meters per second, the throughput is up to 2000 people per hour.
9. In 2011, the Medeo skating rink suffered two hurricanes that felled more than 10,000 trees. More than 2,000 Almaty residents took part in cleaning the tract.
10. helio
11. The road offers a very picturesque view of the mountains and valley.
12. The Almaty TV Tower, located on Mount Kok-Tyube at an altitude of 1000 m above sea level, is the tallest building in Almaty. Its height is almost 372 m. Above sea level - 1130. The base of the tower is a reinforced concrete foundation in the form of a three-story sectional basement. The tower trunk is a metal stepped hexagon with a diameter of 18 m at the base, 13 and 9 m at the locations of maintenance services at heights of 146 and 252 m. The building was built taking into account the mountainous terrain and can withstand an earthquake of up to 10 points. The television tower is a complex of radio and television transmitting stations, and it is not accessible for sightseeing tours of the city. Illuminated at night by powerful spotlights, the tower is visible from almost anywhere in the city. The TV tower is the tallest TV tower in the world, relative to sea level.
15. Construction of the Medeo dam began in 1964 and was carried out using blasting. The first stage rock-fill dam, 107 meters high, formed a reservoir with a capacity of 6.2 million cubic meters and was put into operation in 1972. After a mudflow in 1973, which almost filled the mudflow reservoir (the dam retained a mudflow volume of 4.8 million cubic meters and up to 1.5 million cubic meters of mudflow flood waters), it was completed - the completion of the construction of the second stage of the dam in 1980 significantly increased the capacity of the mudflow reservoir to 12 .6 million cubic meters, the height of the dam was increased to 150 m, its length along the crest was 530 m, and its width at the base was 800 meters.
16. Working moments:)
Mudflow protection dam, a unique engineering protection structure against mud-stone flows in the Medeu tract, is located 15 km south of Almaty in the mountain valley of the Malaya Almatinka River (1750 m above sea level).
Monument of architecture, engineering and technical art.
The project was developed by the Kazakh branch of the Hydroproject Institute (chief engineer G.I. Shapovalov). Academicians M.A. Lavrentyev, M.A. Sadovsky, N.V. Melnikov and L.I. Sedov acted as consultants for the construction of the dam. The Medeo dam was created in two stages. The first stage of the dam, 110 m high, with a mudflow storage capacity of 6.2 million cubic meters, was created for the first time in world practice using directed explosions in October 1966 and April 1967 (8.5 million cubic meters of soil were placed in the body of the dam; explosions of more than 2.5 million cubic meters). The author of the project is senior engineer of Soyuzvzryvprom A.N. Kobzev, head of explosion, manager of the Kazakhvzryvprom trust I.Ya. Itter. On September 27, 1966, the first convoy of cars with explosives passed through the streets of Almaty, towards the site of the future dam. It was planned to build a dam museum, where visitors could listen to all the nuances of the explosion on October 21, 1966, recorded for posterity on tape, and see all the delights of the explosion from films and photo panoramas.
The second explosion on April 14, 1967 was less successful. Half of the work had to be carried out by mechanization, using the method of popular construction, with the involvement of mainly military reserves. Thus, mudflow protection measures provoked a catastrophic mudflow on July 15, 1973. The mudflow, which in its power surpassed all glacial mudflows on Malaya Almatinka and was close to the rain mudflow of 1921 and the glacial mudflow of 1963, which took place along the Issyk River. The completion of the construction of the 2nd stage of the dam in 1980 significantly increased the capacity of the mudflow storage facility (up to 12.6 million cubic meters), the height of the dam was raised to 150 m, the length at the crest was 530 m, and the width at the base was 800 m. According to calculations, it can delay the flow, three times the volume of the 1973 mudflow.
When the 17-meter gabion dam in Mynzhilki was broken (3 thousand m above sea level), the maximum water flow reached 250 cubic meters per second (when passing the Gorelnik tourist center it was already 3200, and at the entrance to the mudflow reservoir - 5180 cubic meters per second). The mudflow of 1973 with a mass of 5.3 million cubic meters cut off the road under construction, equipment, power supply, and people who intended to fight nature. At 18:17 the “dragon of the mountains” reached the dam, and for three hours tried to break through it. A mud-stone sea was formed. The movement of the flow was accompanied by a strong roar and shaking of the slopes. It is clear that after such furious work, the mudflow did not leave intact more than one hydraulic structure, which was supposed to hold back the flow in the project. For example, through-through mudflow traps, special structures that were secured with concrete. The trusses themselves, welded from steel 40-centimeter I-beams, each weighing 27 tons, secured by eight pairs of steel cables to anchors embedded in the rocks, were torn out like rotten threads during the mudflow. After the passage of the stream, due to severe deformation and instability of the slopes of the valley, the mudflow hazard of the Malaya Almatinka River sharply increased. The mudflow protection rockfill dam took the brunt of the disaster, however, there was no free volume left in the mudflow reservoir to contain new catastrophic mudflows. The picturesque mountain gorge has turned into a desert canyon. The mudflow destroyed the residential buildings of the Gorelnik tourist center and caused great casualties (in fact, after the tragic event, the sports and recreation areas were closed forever).
In the history of Almaty, geological disasters are known that occurred on May 28, 1887 and December 22, 1910 (old style), crushing mudflows in 1921, 1956, 1973, which significantly influenced the development of architecture and urban planning, the construction and operation of mudflow protection structures (Kazglavselezaschita). Construction of the dam began in 1964. Three large mudflow retention dams were built, incl. 150-meter rock-fill dam Medeo with a mudflow storage capacity of 12.6 million cubic meters. Length along the crest 530 m, width at the base 800 m. A significant amount of work was carried out with powerful directed explosions. The dam failed in 1973. the pressure of the mud-stone mass and flood waters, part of them was diverted using a system of artificial structures (water intake, metal siphon, etc.). To guarantee the discharge of the liquid component of the mudflow, two tunnel spillways were laid in the left part of the dam. In addition, the dam has a tower-slot spillway. Anti-avalanche “hedgehogs” have been installed on the slopes of Mount Mokhnatki. The dam has three successive levels of height. At the site of the first, highest point of the dam, a panorama was built, the so-called. "swallow's nest" A staircase known to city residents and tourists, consisting of 842 concrete steps with verandas, leads to the dam. City running competitions are held regularly to climb this unique staircase.
In the river basin Malaya Almatinka (Sarysay river, Kimasar river) a set of mudflow protection measures is being carried out to preliminarily drain water from mudflow-prone moraine lakes, stabilize river beds with systems of blind and through structures, strengthen river banks, and eliminate sources of mudflow formation. However, residential construction is underway, as well as the construction of roads and chairlifts in the subalpine and forest zones, on the slopes of the Chimbulak and Tuyuksu ski resorts, and the Talgarsky high-mountain pass.
Alma-Ata is located in a basin at the very foot of the Trans-Ili Alatau ridge of the Tien Shan system, separating the endless steppes of Kazakhstan and the basin of the Issyk-Kul mountain lake. From Almaty to Issyk-Kul across the ridge is only 70 kilometers, and to the border with Kyrgyzstan running along the ridge is 35. The proximity of snow and mountains has always contributed to the fact that Almaty, despite its southern location, has developed winter sports. Today we will get acquainted with the mountain sights of the “Southern Capital” of Kazakhstan.
1. The high-mountain sports complex "Medeo" is located in the mountain tract of the same name at an altitude of 1691 meters above sea level. Everyone has probably heard the name “Medeo” at least once - this world’s largest high-mountain skating rink has long secured its reputation as a “record factory”. The high mountains and the purest glacial water contribute to the excellent speed qualities of the ice, and over 200 world records have been set here over the years. The first skating rink in the Medeo tract was opened in 1951, and the current high-mountain complex was built in 1972. The skating rink is open to everyone from October to May; in the summer there is no ice, but you can roller skate, play football or just take a walk and have a good time. It is easy to get from Almaty to Medeo by regular bus or car.
2. At the entrance to the sports complex.
4. In August there is no ice yet, and people on Medeo are involved in summer sports. And in this photo you can see a huge dam rising in the background, protecting Alma-Ata from mudflows coming down from the mountains.
5. Near Medeo there is the lower station of the cable car, leading even higher to the Chimbulak ski resort, located at an altitude of 3100 meters. We sit in the booth and soon admire the high-mountain skating rink from a bird's eye view.
6. The cable car passes directly above the mudflow dam, protecting the city below from an invisible but terrible danger. The proximity of the mountains has always posed a threat to Almaty - for example, in 1921, a mudflow hit the city from the mountains, which claimed more than 500 lives and destroyed about a quarter of the city's buildings. Less destructive were the mudflows of 1887, 1910, 1918 and 1956. Thus, in the second half of the 20th century, protecting a city of a million people from a new, much more serious, mudslide threat again became more relevant than ever. The construction of a huge dam in the bed of the Malaya Almatinka River began in 1964 and was carried out using blasting operations. In 1972 the dam was built.
7. And already in the next summer, 1973, the dam stopped a terrible mudflow with a volume of more than 6 million cubic meters - five times more powerful than the one that destroyed the city in 1921! It’s hard to say when the next mudflow will come: the mountains are constantly being monitored in this regard. But the main thing is that Alma-Ata is now protected by a reliable shield, and the mountains no longer pose a threat to the beautiful city. Today, after the work is fully completed, the mudflow protection dam in Medeo can withstand a mudflow three times larger than the one that came down from the mountains in 1973.
8. Behind the dam there is a mudflow reservoir. Today it is empty.
9. Drainage pipes are installed in the body of the dam, which, in the event of a mudflow and filling of the mudflow reservoir, ensure the outflow of water from the Malaya Almatinka River.
10. We rise higher. In the side valleys that branch off from the main one, smaller mudflow barriers are also installed.
11. The bulk of the main ridge of the Trans-Ili Alatau appeared ahead.
12. We are at the bottom station of the Chimbulak ski resort. It's summer, not the season, but there are still a lot of tourists. As a skier, it was interesting for me to explore the slopes of Chimbulak - they are not bad in principle; and there are even “black” tracks! :)
13. The next cable car leads even higher.
14. It’s summer now, but the cannons are still working - they moisten the soil of the ski slope, where excavation work is carried out in the off-season.
15. We reach the very top - there are mountains all around, and somewhere far, far below in the haze Alma-Ata is visible. How nice it must be to live in a city where such a cool ski resort is literally within walking distance! I would probably ride every day! :)
16. Majestic landscapes of the Trans-Ili Alatau.
18. View of Alma-Ata from the mountains. Gorgeous!!!
19. The height of the Talgar Pass is 3180 meters. At first, when you just get out of the lift cabin, you feel a lack of oxygen, but then you get used to the altitude and it goes away. In any case, I need to train - I have one very serious mountain climb in my immediate plans.
21. Several “home” peaks of Alma-Ata adjoin the Talgar Pass and the highest point of the Chimbulak resort - Chkalov Peak, Nursultan Peak (formerly Komsomol Peak), Shkolnik Peak, Fizkulnik Peak and others. The height of the mountain range separating the steppes of Kazakhstan from Lake Issyk-Kul in Kyrgyzstan is 4000-4600 meters. What it must be like to find yourself at the very top of the ridge: in one direction - Kazakhstan and Alma-Ata, and in the other - Issyk-Kul and Kyrgyzstan.
22. Relax in the mountains - and just enjoy!
24. I wonder if Issyk-Kul can be seen from there?
26. The Kyrgyz-Issyk-Kul topic is very close to Seryoga and me - after all, just two months before we visited the other side of the ridge and had a lot of rides around Kyrgyzstan. And now here we are on the other side of these mountains, in Kazakhstan - but comrade
