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CE 458 Design of Hydraulic Structures. by Dr. Nuray Denli Tokyay. 1- 3 Historical Perspective and Trends for Future. Ancient Hydraulics Works in Egypt and Other Early Civilizations : Early civilizations developed in regions :
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CE 458Design of Hydraulic Structures by Dr. Nuray Denli Tokyay
1-3 Historical Perspective and Trends for Future Ancient Hydraulics Works in Egypt and Other Early Civilizations: Early civilizations developed in regions: • where an abundance of water could be distributed over fairly flat land for irrigation, and • where a warm climate produced a fast growth of crops. Thus, it is hardly surprising that the earliest remains and accounts of water control were to be found in: • Egypt, • Mesopotamia (Iraq), • the Indus Valley (India and Pakistan), and in • the Yellow River Valley of China.
Egypt is particularly interesting in this regard because the natural features of the Nile River and even the prevailing winds favored the development of a robust civilization. The annual floods over the rich delta land allowed agriculture to flourish even though many people had to move to higher lands during flood season. • To augment the flow of irrigation water during the low flow season, there are signs that one of the early rulers, • King Menes (about 3000 B.C.), had a masonry dam built across the Nile near Memphis (about 23 km upstream from present-day Cairo). • This dam was apparently used to divert the river into a canal and, thus, to irrigate part of the adjoining arid lands. • As reported by Biswas (1), “the gravity dam seems to have had a maximum height of about 15 m and a crest length of some 450 m ”.
Egypt was one of the first civilizations to develop an extensive system of river navigation. • The Nile traversed the entire length of the country and, in the Delta, divided into seven delta channels, thus providing an extensive system of waterways. • A climatic factor favoring the development of water transportation was that the prevailing winds (especially during the summer months) blow from north to south (from the Mediterranean Sea to the Sahara Desert). • However, the river flows from south to north so that boatmen used sails to navigate upstream and leisurely drifted downstream (without sails) during the return trip. This mode of transportation is still seen today.
Prevailing winds (especially during summer) River (direction of flow)
Civilization in Mesopotamia started about the same time as in Egypt (about 3000 B.C.), and the geography of the two areas is in many ways similar. The Euphrates and Tigris rivers formed a network of channels before finally emptying into the Persian Gulf. Furthermore, the people of the area built many canals for irrigating crops, draining swamps, and water transportation. Early hydraulic “engineering” in this area included developing flood protection works and dam construction. • Ancient ruins in the valleys of the Indus River in Asia and the Yellow River in China reveal evidence of water systems developed at least 3000 years ago; however, records of the extent of this development are not as complete as for Egypt and other areas of the Middle East .
Arabic:Al Furat Turkish: Fırat The Euphrates River is one of the most important rivers in the world. Along with the Tigris, it provided much of the water that supported the development of ancient Mesopotamian culture. The Tigris Euphrates valley was the birthplace of the ancient civilizations of Assyria, Babylonian, and Sumer. In northern Iraq the Euphrates forms the western boundary of the area known as Al Jazirah. To the southeast the alluvial lands between the two rivers was the site of the glorious Babylonian civilizations of ancient times.
The Euphrates is important solely for its water supply. The river is the source of political tension, as Turkey, Syria and Iraq all compete for the use of its waters for irrigation and the generation of hydroelectric power. For centuries the river formed the east limit of Roman control. During the supremacy of the Eastern Roman Empire, numerous towns and centers of art and literature flourished along its bank. Much historical data has been yielded by archaeological excavations on the banks of the Tigris and the Euphrates.
A different type of ancient hydraulic engineering was developed in eastern Turkey and Persia (Iran) from the seventh to fifth century B.C. • Underground canals, called qanāts, were dug to intercept groundwater aquifers and to carry the water from the source areas to cities. Figure below, shows the details of this system. Biswas (1) notes the average length of a qanāt was about 42 km (26 mi), and in some places it was as deep as 120 m (400 ft). Such ancient water supply systems, some of which still exist, were truly remarkable.
URARTUS (900-640 BC) • Most probably the name Urartu comes from the Assyrian word “uriatri” meaning mountainous area which perfectly fits the geography of Eastern Anatolia where Urartus lived. • Starting with the fourth king, Menua, construction became the main engineering activity in the Urartu Kingdom. During his reign (810-780 BC) besides fortresses, palaces and temples, irrigation canals and roads were started to be built all over the kingdom. • Archeological evidence indicate considerable technical skills of the Urartian people on irrigation and water management, also. • The Menua Canal which was built about 2800 years ago is still in operation. Urartians first exploited a powerful spring in the valley of Ergil Çayı (Ergil Creek) and conveyed about 45 million m3 of water annually to Tushba (Van) for about 56 km. • The seventh king of Urartu, Rusa I (730-713 BC), moved his capital to Sardurihinili.
For this new capital, another source of water had to be found. An artificial lake was created by building two dams in the mountains. The water collected was directed to the city by a natural river bed. Additional water was stored by the dams. Urartian water management system contained all the elements which are used in modern systems: River diversions, transfer of water from one catchment area to another and water storage by dams [GARBRECHT 1987]. • It is obvious that the knowledge of hydrotechnology and road construction passed from one king to another. Therefore, the technical skills are taught by some means or another. Unfortunately, no written evidence was found yet on how this transfer of knowledge was done.
Roman Water Systems • From about 200 B.C. to 50 A.D., the Romans developed elaborate water-supply systems throughout their empire. • For Rome itself, the usual practice was to convey water from springs to an aqueduct and then to cisterns throughout the city from which water was delivered to consumers through lead and baked-clay pipes. Hadas (5) reports that 11 aqueducts supplied Rome with about 750 million liters (750 000 cubic meter, 200 million gallons) of water daily. • The aqueducts consisted of one or more channels of rectangular cross section and in some locations were supported on spectacular masonry arches. The channels, which were from 60 to 180 cm (2 to 6 ft) in width and from 1.5 to 2.5 m (5 to 8 ft) in height (11), were covered to prevent the water from being contaminated by dust and heated by the sun. Inspection holes were in channel covers about every 75 m (250 ft) (11).
Notable Dams Built in This Century The need for more water resources during this century is the result of a rapidly expanding world population and industrial growth. New machines and methods for manufacturing and placing large quantities of concrete and improved earth-moving equipment provided the means to achieve the rapid growth in major hydropower, irrigation, and flood control projects. In almost all cases, dams are the backbones of these water-resources projects. For hydropower development, a dam is generally needed to develop the head to drive the turbines and to store water to allow power generation. For flood control, dams are used to form reservoirs, which reduce flood peaks by storing the peak flows of flood water. Even a dike constructed to prevent flooding of property near a river is a form of dam. Dams in the United States that are over 15 m high or between 10 m and 15 m high and impound more than 100,000 m3 (81 acre-ft) of water number about 3,000 (9). At the beginning of this century, only 116 of these dams had been built (9).
Table 1-1, lists the world’s major dams. The two highest dams are constructed of earth, which may be surprising to many because we often think of concrete as the material from which high dams are made. However, since availability of material and the strength of the foundation dictate the type of dam to be designed and constructed, earth is often used. Abbreviations are as follows: E= earthfill, R= rockfill, G= gravity, A = Arch.
Table 1-1 Major Dams of the World (Highest Dams) Abbreviations are as follows: E= earthfill, R= rockfill, G= gravity, A = Arch.
Atatürk Dam Atatürk Dam, largest dam built in Turkey, serves for: • irrigation, • power generation and water supply. It is one of the dams built in GAP (South Eastern Anatolian Project), one of the largest water resources development projects in the world. It is located in 70 km northwest of the city of Şanlıurfa on the Euphrates River. • Embankment type is rockfill with inclined clay core. Ataturk Dam, having 184 m height from foundation, is the fourth highest dam in Turkey following Keban, Altınkaya, Karakaya and Altınpınar dams.
Among rockfill dams in the world, It’s the 25 th, regards its height, 5 th, embankment volume, 21 st, reservoir volume and 32 nd installed power of HEPP. Atatürk HEPP has been in operation since 1993. It has an annual power generation capacity of 8.9 billion kWh. Its capacity will fall to 8.1 billion kWh per year when irrigation projects are completely implemented. The dam will make it possible to irrigate approximately 882,000 hectares of land.
The Şanlıurfa Tunnels and Irrigation Projects • The two Şanlıurfa Irrigation Tunnels, longest irrigation tunnels in the world, start from the reservoir of Atatürk Dam and lie parallel to each other from 5 km northeast of the city of Şanlıurfa to Şanlıurfa-Harran plains. • The tunnels are circular and concrete lined with diameters of 7.62 meters and lengths of 26.4 kilometers each. • With the addition lengths of access and connection tunnels, total length of the tunnels reaches 52.8 kilometers
By means of the Şanlıurfa tunnels, the water stored in the reservoir of Atatürk dam will be used for Şanlıurfa-Harran and Mardin-Ceylanpınar plains. Thus, irrigated agriculture will take place in 476 000 hectares of land of these plains, 150 000 hectares of Şanlıurfa-Harran plains, 326 000 hectares of Mardin-Ceylanpınar plains. • 328 cubic meters of water per second is drawn from the Atatürk Dam Reservoir with these tunnels. • The water used to irrigate plains of Şanlıurfa-Harran will also be deployed for power generation at the Şanlıurfa HEPP. • The HEPP has a capacity of 50 MW and generates 124 million kWh electricity annually.
Rivers and Lakes Turkey has about 120 natural lakes, including small lakes in the mountains. • The largest and deepest lake is Lake Van with a surface area of 3,712 km 2 and an altitude of 1,646 m from sea level. • The second largest lake is Lake Tuz in central Anatolia. Being relatively shallow, this lake is at an altitude of 925 m from sea level and has a surface area of 1,500 km 2. • There are four main regions where lakes are intensively dispersed: • 1. The “Lakes District” (Eğirdir, Burdur, Beyşehir, and Acıgöl Lakes), 2. Southern Marmara (Sapanca, İznik, Ulubat, and Kuş Lakes), 3. Lake Van and its environs, and 4. Lake Tuz and its environs. • Although some of the lakes are only a few meters in depth, some of them are of a depth of more than 30 meters. The depth of Lake Van is more than 100 m. Turkey has 555 large dam reservoirs. The names and surface areas (km2) of the large ones are Atatürk (817), Keban (675), Karakaya (268), Hirfanlı (263), Altınkaya (118), Kurtboğazı (6).
Turkey is rich in terms of streams and rivers. Many rivers rise and empty into seas within Turkey’s borders. Rivers can be classified in relation to the sea into which they empty. • The rivers emptying into the Black Sea are the Sakarya, Filyos, Kızılırmak, Yeşilırmak, and Çoruh. • The rivers emptying into Mediterranean Sea are the Asi, Seyhan, Ceyhan, Tarsus, and Dalaman. • The rivers emptying into the Aegean Sea are the Büyük Menderes, Küçük Menderes, Gediz, and Meriç. The rivers empting into the Sea of Marmara are the Susurluk/Simav, Biga, and Gönen. • The Euphrates and Tigris rivers empty into the Gulf of Basra, while the Aras and Kura rivers empty into the Caspian Sea. • As far as the lengths of the some major rivers are concerned, the Kızılırmak is 1,355 km, Yeşilırmak is 519 km, Ceyhan is 509 km, Büyük Menderes is 307 km, Susurluk is 321 km, the Tigris is 523 km, the Euphrates River up to the Syrian border is 1,263 km, and the Aras River up to the Armenia border is 548 km.
Land Resources • Turkey ’s total land area is 78 Mha. • Almost one third of this, 28 Mha, can be classified as cultivable land. • Recent studies indicate that an area of about 8.5 million ha is economically irrigable under the available technology. • Until now, an area of about 2.8 million ha has been equipped with irrigation infrastructures by DSİ.
Water Resources • Mean Precipitation : 643 mm/m2 • Turkey ’s Surface Area : 780,000 km 2 • Annual Water Resources Potential Bm ³ (billion m ³ ) • A Precipitation Volume : 501 • B Evaporation : 274 • C Leakage into Groundwater : 69 • D Springs Feeding Surface Water : 28 • E Surface Water from Neighboring Countries : 7 • F=A-B-C+D+E • F Total Surface Runoff (gross) : 193 • G Exploitable Surface Runoff : 98 • H Groundwater Safe Yield : 14 • I=G+H • I Total Potential (net) : 112
The total water volume in the world amounts to 1.4 billion km3, 97.5% of which is saline water in the oceans and seas, 2.5% of which is fresh water in the rivers and lakes. • Due to fact that 90% of fresh water exists in the South Pole and North Pole, human beings have very limited readily exploitable fresh water resources. • Annual mean precipitation in Turkey is 643 mm, which corresponds to 501 Bm 3 (billion m 3) of annual water volume in the country. • A volume of 274 Bm 3 water evaporates from water bodies and soils to atmosphere. • 69 Bm 3 of volume of water leaks into groundwater, whereas 28 Bm 3 is retrieved by springs from groundwater contributing to surface water.
Also, there are 7 billion m3 volume of water coming from neighboring countries. • Thus, total annual surface runoff amounts to a volume of 193 Bm 3 of water. • Including 41 (69-28) Bm3 net discharging into groundwater (covering safe yield extraction, unregistered extraction, emptying into the seas, and transboundary), the gross (surface and groundwater) renewable water potential of Turkey is estimated as 234 (193+41) Bm 3. • However, under current technical and economic constraints, annual exploitable potential has been calculated as 112 Bm 3 of net water volume, as 95 Bm 3 from surface water resources, as 3 Bm 3 from neighboring countries, as 14 Bm 3 from groundwater safe yield.
Water Resources versus Water Consumption Needs of Population Countries can be classified according to their water wealth: • Poor: Annual water volume per capita is less than 1,000 m3 • Insufficient / Water Stress: Annual water volume per capita is less than 2,000 m 3 • Rich: Annual water volume per capita is more than 8,000- 10,000 m3
1500 m3/capita Turkey is not a rich country in terms of existing water potential. Turkey is a water stress country according to annual volume of water available per capita. The annual exploitable amount of water has recently been approximately 1,500 m 3 per capita The State Institute of Statistics (DİE) has estimated Turkey’s population as 100 million by 2030. So, the annual available amount of water per capita will be about 1,000 m 3 by 2030.
The current population and economic growth rate will alter water consumption patterns. As population increases, annual allocated available amount of water per person will decrease. The projections for future water consumption would be valid on the condition that the water resources were protected from pollution at least for the next 25 years. It is imperative that available resources be evaluated rationally so as to provide clean and sufficient water resources for the next generation.
Planning Studies in Turkey • Under the scope of DSİ’ planning studies, the most appropriate formulations of projects are prepared by using long-term data collections and investigations. • In 2003, 40.1 billion m3 volume of water was consumed in various sectors in Turkey; 29.6 billion m3 in the irrigation sector, 6.2 billion m3 in the water supply sector, 4.3 billion m3 in the industrial sector. • This sum corresponds to development of only 36.5% of the available exploitable potential of 112 billion m3. • With ongoing studies, it is aimed at using the maximum portion of available potential in the country.
Hydraulic Structures in Turkey • According to the standards of ICOLD (International Committee on Large Dams), providing a dam’s height from foundation is more than 15 m or its reservoir volume is equal or more than 3 hm3, this dam is classified as a “large dam”. As seen from the table below, the number of large dams constructed by DSİ is 544. • If eleven large dams constructed by other institutions are added to this, the total number amounts to 555 dams. • DSİ has built 201 large dams within the framework of large-scale water projects, while the remaining 343 dams are within the framework of the smaller-scale water projects. • The total reservoir capacity of these 212 large dams is about 139.5 km3. The details on water resources development can be seen in the table:
(*) Small dams built by the General Directorate of Rural Services (GDRS abrogated now) for irrigation.
According to ICOLD standards, there are at present 555 large dams, in Turkey. • According to crest types, these dams can be classified as follows: • Rock or earth-filled types: 537 dams • Concrete gravity types: 8 dams (Çubuk I, Elmalı II, Sarıyar, Kemer, Gülüç, Porsuk, Arpaçay, Karacaören) • Arch types : 6 dams (Gökçekaya, Oymapınar, Karakaya, Gezende, Sır, Berke) • Composite (Concrete Faced Rock-Fill Dam –CFRD or RCC) types: 4 dams (Kürtün, Birecik, Karkamış, Keban)
Dams and Hydropower Plants Developed by other Organizations Total installed capacity (MW) and annual averagegeneration (GWh) of hydroelectric power plants (run-off river HEPPs) completed by the other organizations are 2,416 MW and 8,844 GWh respectively . These values account for 20% of Turkey’s current hydropower installed capacity (12,631 MW) and annual hydroelectric generation (45,325 GWh). The HEPPs put into operation by DSİ generate 80% of Turkey’s current hydro energy needs. According to DSİ’s investment program in 2005, there is a total of 53 HEPPs, 24 of which will be realized with bilateral agreements (6,136 MW and 20,203 GWh) and 5 of which are to be realized with local bidding (124 MW and 458 GWh), and the remaining 24 of which are under construction (2,722 MW and 8,920 GWh).