One of the most striking examples of hydrodynamic accidents was the event in California, only seventy kilometers from Los Angeles (Canyon San Francisco). The reservoir began to fill in 1972, but the maximum level was reached after a year. Water seeping through the dam was already worrying, but the authorities did not respond to complaints from local residents. The trouble came in March 1928 . The dam could not withstand the pressure of water breaking through the thickness of the soil, and collapsed. A 40-meter liquid wall demolished a power plant built 25 km after 5 minutes. All living things along with the buildings were destroyed. Then a stream covered the valley. Here, his strength weakened a little, but continued to sweep away everything in his path, moving towards the coastal plain. By this time it was already a three-kilometer stream of mud, which claimed the lives of six hundred people ...
What are the types of hydrodynamic accidents? Can they be avoided?
Hydrodynamic accidents are mostly predictable and predictable, but human carelessness allows them to happen. Alas, the natural factor in the form of earthquakes, hurricanes, landslides, landslides and floods becomes the cause of the tragedy much less often than the human factor. Hydrodynamic accidents occur more often due to errors in design, structural defects of structures, violations of operating rules, insufficient spillways and overflow of water through dams. In addition, do not miss the opportunity to sabotage and strike at such facilities.
Hydrodynamic accidents are the result of the failure of hydraulic structures, as a result of which an uncontrolled powerful stream of huge masses of water floods vast territories with great speed, causing destruction and loss of life. Flooded areas are divided into 4 zones.
The first is in close proximity to the hydraulic structure and within a radius of 12 km from it. The speed and height of the flow depends on the nature of damage to hydraulic structures, their fullness before the accident and altitude. Here the destruction is most widespread.
In the second and third zones, the current velocity and wave height drops significantly (the geographical indicators of the area are decisive here: hills, slopes, plains, etc.).
The fourth zone includes areas of weak currents, where the speed is about 8-9 km / h, and the length depends on the topography of the flooded area.
It is the first zones where there are massive losses of people and destruction (and more often complete destruction) of structures that are considered areas of catastrophic flooding.
Are hydrodynamic accidents possible in Russia? Judge for yourself. Tens of thousands of reservoirs have been built in the country, with a capacity of sixty of them - over a billion cubic meters. The accumulators of industrial wastes and drains are ten times larger. And all of them are potentially dangerous objects. These include not only artificial structures (pools, dams, dams, dams, leveling reservoirs, etc.), but also natural formations with a difference in water level (upper pool / lower pool). Note: out of 300 officially registered dam accidents over the past one and a half hundred years, more than 30% occurred due to excess discharge flow.
Unfortunately, there are many examples of such disasters on the territory of the Russian Federation: 1993 - Kiselevsky reservoir (dam break), 1994 - Tyrlyanskoye reservoir, p. Belaya (dam destruction), 1994 - Primorye (flood), 1999 - Yakutia (and the tragedy repeats after only two years), 2002 - Krasnodar Territory (flood and destruction of the hydroelectric complex).
The last tragedy happened in July 2012, in Krymsk. Specialists still understand its causes, and people continue to search for their missing relatives.
It turns out that for the last 25 years the dam has not “seen” the overhaul. In the event of an accident, the wave could cover about half a million people. Six years ago, the dam was in disrepair. In some places, the gaps reached 50 cm. Sergei Shoigu, the head of the Ministry of Emergencies in Russia, described the situation as very difficult. Local residents also repeatedly notified the relevant authorities about the danger. The official report, dated 2010, confirmed the serious danger. But until the thunder strikes ...
And he burst out. On the night of June seventh, a huge wave covered sleeping people in Krymsk, Novorossiysk, Gelendzhik. The death toll is still being calculated. Official figures call the figure of 200 people, while residents themselves say that there are more deaths at times ...
No matter how bitterly, the salvation of the drowning continues to be the work of the drowning themselves. And well, if the population has time to notify of impending disaster. And if not? What to do if the flood comes suddenly?
Take the highest place (tree, roof of the house). Hang a banner to find you on. Only light signals are clearly visible at night. If water is already at the doorstep, without hesitation, build a raft from improvised means. If you find yourself in water, grab onto large floating objects. Do not panic. Keep calling for help and signaling. Beware of electrical wires and sharp parts of debris. Do not drink water without treatment. Do not consume any food in this water.
After the decline of water, entering the house, open wide the doors and windows. Turn on gas and electrical appliances only after thorough ventilation and with complete confidence that the devices and wiring are in good working order.