CE 458 Design of Hydraulic Structures

1. CE 458Design of Hydraulic Structures by Dr. Nuray Denli Tokyay

2. 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.

3. 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 �.

4. 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.

6. 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 .

8. Euphrates and Tigris rivers

9. Arabic:� Al Furat Turkish: Firat 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.�

10. 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.

13. 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 qanats, 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 qanat 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.

14. Details of ganat system

15. 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 �ayi (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.

16. 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.

17. 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).

18. 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).

19. 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.

20. Table 1-1 Major Dams of the World (Highest Dams)

21. Greatest Volume

22. Greatest Hydropower

23. Atat�rk Dam Atat�rk 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 Sanliurfa 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, Altinkaya, Karakaya and Altinpinar dams.

28. TECHNICAL DATA FOR THE DAM

30. The Sanliurfa Tunnels and Irrigation Projects The two Sanliurfa Irrigation Tunnels, longest irrigation tunnels in the world, start from the reservoir of Atat�rk Dam and lie parallel to each other from 5 km northeast of the city of Sanliurfa to Sanliurfa-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

31. By means of the Sanliurfa tunnels, the water stored in the reservoir of Atat�rk dam will be used for Sanliurfa-Harran and Mardin-Ceylanpinar plains. Thus, irrigated agriculture will take place in 476 000 hectares of land of these plains, 150 000 hectares of Sanliurfa-Harran plains, 326 000 hectares of Mardin-Ceylanpinar plains. 328 cubic meters of water per second is drawn from the Atat�rk Dam Reservoir with these tunnels. The water used to irrigate plains of Sanliurfa-Harran will also be deployed for power generation at the Sanliurfa HEPP. The HEPP has a capacity of 50 MW and generates 124 million kWh electricity annually.

35. 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� (Egirdir, Burdur, Beysehir, and Acig�l Lakes), 2. Southern Marmara (Sapanca, Iznik, Ulubat, and Kus 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 Atat�rk (817), Keban (675), Karakaya (268), Hirfanli (263), Altinkaya (118), Kurtbogazi (6).

36. 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, Kizilirmak, Yesilirmak, and �oruh. The rivers emptying into Mediterranean Sea are the Asi, Seyhan, Ceyhan, Tarsus, and Dalaman. The rivers emptying into the Aegean Sea are the B�y�k Menderes, K���k Menderes, Gediz, and Meri�. The rivers empting into the Sea of Marmara are the Susurluk/Simav, Biga, and G�nen. 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 Kizilirmak is 1,355 km, Yesilirmak is 519 km, Ceyhan is 509 km, B�y�k 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.

38. 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 DSI.

39. Water Resources Mean Precipitation : 643 mm/m2 Turkey �s Surface Area : 780,000 km 2 � Annual Water Resources Potential Bm � (billion m � ) 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

40. 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.

41. 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.

43. 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

45. 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.

46. Planning Studies in Turkey Under the scope of DSI� 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.

47. 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 DSI is 544. If eleven large dams constructed by other institutions are added to this, the total number amounts to 555 dams. DSI 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:

49. 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 (�ubuk I, Elmali II, Sariyar, Kemer, G�l��, Porsuk, Arpa�ay, Karaca�ren) Arch types : 6 dams (G�k�ekaya, Oymapinar, Karakaya, Gezende, Sir, Berke) Composite (Concrete Faced Rock-Fill Dam �CFRD or RCC) types: 4 dams (K�rt�n, Birecik, Karkamis, Keban)

50. Dams and Hydropower Plants Developed by other Organizations Total installed capacity (MW) and annual average generation (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 DSI generate 80% of Turkey�s current hydro energy needs. According to DSI�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).

51. The number of hydroelectric power plants being constructed by other organizations under Law No. 3096 is 17 (465 MW and 1,725 GWh). These are being built as Autoproducer or BOT (Build-Operate-Transfer) models by the private sector. Since its establishment in 1954, DSI has made investments of US$ 33.5 billion, and the total benefit from these projects realized by DSI in the sectors of energy, agriculture, services, and the environment is estimated as US$ 81 billion. These projects have made a more than two fold contribution to the national economy when considering their investment costs.

53. Since its establishment in 1954, DSI has made investments of US$ 33.5 billion, and the total benefit from these projects realized by DSI in the sectors of energy, agriculture, services, and the environment is estimated as US$ 81 billion. These projects have made a more than two fold contribution to the national economy when considering their investment costs. With the budget allocation for 2005, DSI needs 19 years to complete the projects in its investment program. For the full development of the water projects in Turkey, as seen in the table below, US$ 71.5 billion is needed for completion of the remaining projects. Considering development rates in the country, there is still much work to do in the water sector. By taking into account the investment budget of DSI (annual US $1.65 billion), it is estimated that the completion of the works (US$ 71.5 billion budget) to be realized by DSI could only be possible in the next 44 years.

55. In conclusion, the distribution of precipitation in Turkey is rather uneven. The average annual precipitation ranges from less than 250 mm in inland areas to 2,500 mm in parts of the Eastern Black Sea coast. Though Turkey generally has adequate amounts of water, it is not always in the right place and at the right time to meet present and anticipated needs. The rivers have generally irregular regimes and natural flows cannot always be diverted directly. The average annual precipitation, evaporation, and surface runoff vary with respect to time and geography. Approximately 70% of total precipitation falls from October to March; there is little effective rain during the summer months. Therefore, it is necessary to have storage facilities in order to ensure domestic, industrial and agricultural supply, and hydropower generation. In addition, dams make a considerable contribution to control the floods and erosion.

56. The water resources development projects of DSI are accepted as crucially important works for the improvement of the welfare and happiness of the people in the country. It is a well-known fact that the main source of daily food, drinking water, and electricity depend on water resources development projects. That is why Turkey has to develop all of her water potential to maintain adequate living standards for the people. Agriculture in Turkey heavily depends on climatic conditions, the adverse effects of which can only be minimized by developing hydraulic structures. DSI contributes to the development of agriculture in which 35% of Turkey�s population is employed by investing mostly in development of irrigation sector. As the production and consequently the income of our farmers increases because of irrigation development, there are further inputs to agro-industries.

57. Because of this, water resources development has a crucial role to play in the socioeconomic development of Turkey. Thus, DSI�s investments in hydropower, which is a national source of the electricity needed by industry are important in that they are able to lessen the rate of migration to the cities and to decrease the unemployment in the country. DSI needs a certain amount of financing to complete its planned projects in the sectors of energy, agriculture, services, and environment by 2030. This additional financing requirement is estimated at US$ 71.5 billion (as 27.5 in agriculture, 21.0 in energy, 20.0 in services, and 3.0 in environment). With the completion of these planned projects, Turkey foresees to have US$ 27.8 billion worth of gross income annually.