The only flood protection system know nowadays is building dikes, reservoirs and pumping stations running on electric or mechanical energy. The subject of the invention is a system allowing to prevent flooding while the excess water caused by flooding is transformed into electric energy. The way of building the system and its application according to the invention is presented in the enclosed drawings.

Power generation and flood protection system works using the commonly known principle of water lever. The name "water lever is" colloquial. The manner of the water lever operating is illustrated in Fig. 1. A hose is placed in a liquid tank and then the liquid is sucked up. In order for the water lever to work one essential condition must be met. The level of the liquid being suck up (Point A) has to be above the level of the liquid leaving the hose at all times (Point B) . Provided this condition is met, the water lever works regardless of the fact whether the hose is coiled and the liquid, first of all, has to go up and then down. The working principle of the whole system according to the invention is presented in Fig.2.

STRUCTURE

On the bottom of a river no. 2 or underneath a pipeline no. 3 is assembled. Every several dozens of kilometres the pipeline no. 3 is led out of the bottom high up above the water surface (this is accomplished by structure no. 5). The pipeline no. 3 has inlet holes no. 1 herein after called in-holes. The pipeline no. 3 has also drain holes no. 10 hereinafter called out-holes. In-holes no. 1 are always above the out-holes no. 10. In the pipeline no. 3, immediately over an out-hole no. 10 a water turbine (e. g. rotary or other type on the outside) connected to a electricity generator no. 9. The pipeline no. 3 is also fitted with feed-drain valves no. 7 and 8. The pipeline is fully filled with water which required sucking up the so-called water lever early on, located above the river surface at the structure's height. The sucking up is needed only for the first start-up of the system. Next start-ups do not require the sucking since after closing the valve no. 8 water still remains in a section of the pipeline no. 6. Each following system start-up only requires opening the valve no. 8. FOOD PREVENTION AND PRODUCTION OF ELECTRIC POWER

All existing rivers in the world flow high land down to the sea and thus using the so- called water lever to prevent floods does not cause any problems. When, as a result of rainfall or melting of snow, the water level in a river no. 2 begins to rise, the valve no. 8 and the valve no. 7 (if it exists) should be opened. At the moment of the opening of the valve no. 8 the excess of water from point A is instantaneously moved to point B which may be a few dozens or hundreds of kilometres away from point A (flooding threat). After the system has been started, at flood-threatened point A the water level will begin to fall while at the point B not threatened by a flood where the riverbed is capable of holding the excess of water from point A, the water level will rise. The excess of water from the flood region (A) can be simultaneously transferred to other points (e.g. C, D, etc., always downstream). Making a theoretical assumption that a river is 1,000 km long and its origin is situated 2,000 m above sea level, such a river can have 20 points A, B, C, D, etc. and each one of them can be at the distance of 50 km. The level difference between the points (in-holes and out-holes) equals 100 m. With the level difference at 100 m the water pressure at the out-hole in point B will be approximately 10 atm. Assuming that the pipeline no. 3 diameter is 1 m, the amount of water being transferred from point A to point B will be several m ³ /s. Adding it all up, within one hour approximately 10,000 m ³ of water will be transferred from point A to point B (absolutely for free, without using pumps). The excess flood water ought to be used to produce electric power since we get a lot of m ³ of water at a high pressure. Water can be transferred from point A to B and from point B to C and so on all the way to the sea. According to the invention the system can transfer flood water twenty and more times and, while doing this, generate electric power supplied to the national grid. In the description an example of a 1 metre of diameter pipeline has been illustrated. The actual structure can consist of, for instance, six pipeline of the diameter equalling 1 metre. The power generation and flood protection system can, at the time when floods do not occur, work as a power generating system only. It can be used exclusively for power purposes by building a pipeline between water basins going from the higher land down. In this case point A has to be a natural water reservoir. The remaining points B, C, D etc. Can be man-made reservoirs. During the system's operation the water level in artificial reservoirs will be the same although the water will be constantly on the move. The advantage of the system according to the invention is the fact that thanks to it floods can be prevented. The water lever in a river can be adjusted before heavy rains appear. Moreover, the water level in the river can be lowered and, by doing so, prepare the riverbed to take in excess water. Another advantage of the system is that the excess of flood water can be transformed into electric power. The biggest advantage of the system is its economic efficiency.

Today the government wishing to build reservoirs has to buy land from private owners. Often it involves a compulsory purchase which, in consequence, results in high compensations or leads to lengthy lawsuits. The system according to the invention solves this problem entirely. A river with its bottom is in the possession of the state, hence, every government resolving to apply the flood protection system according to the invention shall save both time and money (as well as flood induced costs). Furthermore, building the system costs less than building dikes, reservoirs, pumping stations, etc. Nowadays there is a number of know technologies allowing a fast building of pipelines with the use of flexible plastics of very big strength. The costs of building the system will begin to repay itself right after heavy rains or melting of snow occurs. Electricity produced thanks to the system will be sold and thus the investment will start to refund. The Power Generation and Flood Protection System is quite timely because we live in the era of the global warming. Floods will become increasingly frequent and year after year can be more troublesome. Instead of spending money on flood damage repair it will be better spent on flood prevention. Today, if a river level rises by, for example, 3 m and it does not constitutes a flood threat, nothing is done about it. Water flows down to the sea without generating either profits or losses. Applying the system according to the invention, a redundant excess of water can be used transforming it into electric power. It is possible because we have inside the pipeline we have water high pressure (completely for free).