a group of structures used for hydroengineering purposes and unified by their arrangement and by a common operational purpose. Hydroengineering complexes may be categorized by their basic purpose; for example, they may be used in power engineering, in water transportation, or in water intake and consumption management. Most hydroengineering complexes simultaneously serve several purposes of water management.
Hydroengineering complexes may be also categorized by the available head—that is, by the difference in water level between the headrace and the tail water. Low-head complexes, with a head not exceeding 10 m, are located near rivers flowing through plains, mostly within the river bed, and are used mainly for navigational or power-engineering purposes. They may also be situated near rivers in mountainous terrain and used as a water intake for power generation and for land irrigation.
The medium-head complexes, with a head of 10-40 m, are located near rivers flowing through plains or through foothills. They are intended mainly for navigational purposes, for power generation, and for irrigation. The backwater (affluent) created in complexes of this type causes an inundation of the river valley near the headrace (upper pond), thus forming a water storage basin. Such a basin is used for such purposes as the daily or seasonal regulation of the run-off, water clarification by settling, and flood control.
The high-head complexes, with a head exceeding 40 m, are usually designed to serve several purposes simultaneously, such as power generation, navigation, and irrigation.
The structures comprising a hydroengineering complex are either basic or auxiliary. The basic structures ensure the normal operation of the hydroengineering complex; these structures, in turn, can be subdivided into general structures and special structures. General structures include dams, surface and subsurface spillways, structures for removal of ice, sludge, scum, and silt, structures for flow regulation, and connecting structures. Such general structures provide the required head of water pressure, the required capacity of the water storage basin, and other hydraulic conditions called for by the changing hydrological state of the river. Special structures include hydroelectric power stations, ship locks, ship hoists, fishways, log chutes, and raft passages.
Auxiliary structures include living quarters, administrative and supply offices, buildings for cultural and community services, and structures required for water supply, sewerage, and roads. Temporary structures (cofferdams, storerooms for construction materials, concrete shops and reinforcement shops, workshops, access roads) are usually functional only during the construction of a hydroengineering complex, but sometimes such temporary structures are integrated into permanent structures (for instance, a cofferdam may become a part of a permanent dam). Sometimes there are additional structures, such as transit roads and bridges crossing the site of a hydroengineering complex (for instance, the crossing of the Kalinin railroad by the Moscow Canal at the site of lock no. 8). A territorial connection may also exist between a hydroengineering complex and those industrial establishments that spring up near the site of this complex, mainly in order to use the available power or other services.
The arrangement of a hydroengineering complex—that is, of the structures that form the so-called head front—is called the line-up. The respective location of the basic structures is called the layout of the complex. The layout presents a complicated engineering problem, which must be solved taking into account operational, structural, technical, and economic requirements. The great variety of environmental and local conditions that can be encountered makes it impossible to establish standardized rules for the arrangement and layout of a hydroengineering complex. These questions are solved individually in each case, taking into account the whole complex of conditions and requirements and considering the character of interaction among buildings.
Besides solving water-management problems, the structures of a hydroengineering complex must also fulfill certain aesthetic requirements. Such structures serve to create an architectural unity, organically integrated into the environment. The whole area of a hydroengineering complex should show a clear-cut architectural and functional zoning. Often a hydroengineering complex influences the planning and building of adjacent old or newly created towns, hamlets, and factories—for example, the Volkhov Hydroelectric Power Plant and the town of Volkhov, the Dnieproges Power Plant and the town of Zaporozh’e. Closely spaced hydroelectric complexes are often built using a common architectural style (for instance, the cascade of the Upper Volga complexes, USSR). The main structures influencing the architectural harmony of a hydroengineering complex are the dam, the hydroelectric power plant, and the ship lock with the head-races. The Krasnoiarsk hydroengineering complex on the Enisei River is used for navigation and for power generation. It includes a spill dam and a fixed dam, a hydroelectric power plant with a capacity of 5 million kilowatts, and a ship hoist located on the left bank of the river. The Nurek hydroengineering complex is being built on the Vakhsh River and is to be used for regulation of the river run-off, irrigation, and generation of electric power. This hydroengineering complex includes the tallest earth-and-stone dam in the world (height, 300 m), a shore spillway, a water-catchment tunnel, and a power plant building.
V. N. POSPELOV