Faculty of Engineering Technology & Research. Isroli, Afwa .

1. Faculty of Engineering Technology & Research. Isroli, Afwa.

3. Water Resources Development 1.Introduction 2.Hydrologic cycle 3.Sources of water 4.Watershed development 5.Water requirements and its conservation 6.Basic introduction of hydrologic structures of srorage (only dams)

4. 1.Introduction • Hydrology is the science which deals with occurrence , distribution and movement of water on the earth.

5. 2. Hydrologic Cycle • Except for the deep ground water, the total water supply of earth is in constant circulation from earth to atmosphere, and back to the earth.

6. The earth’s water circulatory system is known as the hydrologic cycle • water from the surface like lakes, rivers, ocean, etc. converts to vapour by evaporation due to solar heat. • The vapour goes o accumulating continuously in the atmosphere. • This vapour is again considered due to the sudden fall of temperature and pressure. • Thus clouds are formed. • These clouds again cause the precipitation (i.e. rainfall) • Some of the vapour is converted to ice at the peak of the mountains. • The ice again melts insummer and flows as rivers to meet the sea or ocean.

7. These processes of evaporation, precipitation and melting of ice go on continuously like an endless chain and thus a balance is maintained in the atmosphere. • This phenomenon is known as hydrologic cycle. • Thus, the hydrologic cycle may be expressed by the following simplified equation Precipitation = Run off + Evaporation (P) (R) (E) =

8. Application of Hydrology The knowledge of hydrology is very essential for the following application • Determination of the capacity of a reservoir from the rainfall records and the yearly discharge observation of a river. • Determination of peak flow of a river. (peak flood) • Determination of suitable site for hydroelectric power generation. • Sources of water suppy in town or city. • Method to be adopted for the flood forecasting and flood control. • Availability Of water for navigation.

9. Sources Of Water

10. Introduction • Water is a vital natural resources which forms the basis of all life. • It is the most important requirement of plants ,animals and mankind • Water also plays key role in the development of earth’s surface,moderating climate and diluting pollution. • Atmospheric water is the key factor in combination with temperature in influencing the global ecology and as a function of hydrological cycle covering 70% of land surface,it influences weather and global climate and flora and fauna.

11. 71% of earth surface is covered with water. • The pattern of distribution of Earth’s water resources is presented in table.

12. India’s water resources • The basic source of water for india is the rainfall over the most part of the country and snowfall in the northern region. • The rainfall varies from place to place and from year to year. • Normal annual rainfall varies from 100mm in Western Rajasthan to over 11000mm at Cherrapunji in Meghalaya. • The average annual rainfall for the country is about 119.4 cm depth which is nearly 4000km3.

13. Water resources in Gujarat • Water resources in Gujarat state are concentrated primary in the southern and central part of the mainland. • Saurashtra and kutch in the northern mainland with exceptionally high irrigation needs, have limited surface and ground water resources. • Gujarat mainland region receives an average annual of 800 to 2000 mm while saurashtra has an average annual rainfall of 400 to 800 mm. • The annual rainfall in kutch is less than 400 mm.

14. Types Of water sources • The available fresh water is continuously collected, purified and distributed through the hydrologic cycle. • Thus water which is available as fresh water comes from inland surface water sources (such as rivers, streams lakes and reservoirs) and ground water sources.`

15. A. Surface water resources • Most surface water originates directly from precipitation in the form rainfall or snow. • The various surface water sources are described as under:

16. 1.Sea water • As per earth’s water resources distribution, the ocean contain about 97% of the total water in the world. • But as ocean water contain high concentration of salts in solution, it becomes uneconomical to make the water potable.

17. 2.Ponds and Lakes • A natural large sized depression formed on the surface on the earth, when gets filled up with water is known as pond or a lake. • The quality of water in a lake is generally good and does not required much purification. • The quantity of water available from lakes is however, generally small.

18. 3.Streams and Rivers • Rainfall there does not evaporate or infiltrate, runs off the surface towards the sea, in the form of streams and rivers. • River and streams are important sources of water. • The dam is constructed on a perennial river when water is used for multiple uses such as irrigation, hydropower , water supply etc.

19. 4.Impounding reservoirs • A barrier in the form of a dam is constructed across the river, so as to form a pool of water on the upstream side of the barrier. • This pool or artificial lake formed on the upstream side of the dam is known as impounding reservoirs. • The quality of this reservoir water is not much different from that of a natural lake.

20. B. Sub-Surface water sources(Ground water) • The main source of ground water is precipitation. • Water bearing formations of the earth’s crusts act as conduits for transmission and as reservoirs of storage of ground water.

21. Types of aquifer • Aquifer are mainly of two types: • a). Unconfined aquifer • B). Confined aquifer

22. a). Unconfined aquifer • An unconfined aquifer is one in which a free water surface i.e. a water table exists. • In such an aquifer, the water table varies in undulating form and in slope. • A well drilled in this type of aquifer is known as a water table well.

23. Confined and Unconfined aquifer

24. b). Confined aquifer • A confined aquifer is an aquifer which is sandwiched between two Impervious strata. • The water in a confine aquifer is under pressure. • On the other hand, if the water level is below the ground surface, the well water does not flow freely and well is called a non-flowing artesian well.

25. Types of water wells • A water wells may be classified as : • 1). Open wells or dug wells • 2). Tube wells

26. 1). Open wells • Open wells are the wells which have comparatively large diameters but law yields and are not very deep. • The diameter of the open wells usually vary from 1 m to 10 m and yield is about 20 m/hour or less.

27. 2). Tube well • A tube well is a long pipe sunk into the ground intercepting one or more water bearing strata. • Its diameter ranges from 80 mm to 600 mm. • The tube wells may also be further classified as: • A). Shallow tube wells • B). Deep tube wells

28. WATERSHED DEVELOPMENT

29. Introduction • Watershed is the area of land from which drains in to a body of water such as river,lake,stream or bay. Watershed • The area enclosed within the watershed line is known as watershed area.

30. Characteristics of a watershed Several characteristics namely • Size • Shape • Slope • Drainage • Vegetation • Geology • Soil • Climate • land use Size • Sub - watershed 100-500 sq.Km. • milli- watershed 10-100 sq.Km. • Micro - watershed 1-10 sq.Km. • Mini- watershed <1 sq.Km. • The size helps in computing many parameters like rainfall received, retained and drained off.

31. Shape The general shape are • Fan shaped • Leaf shaped • Triangular shaped • Circular shaped Land • Type of land, its altitude and physical disposition immediately says about a watershed as to the climate and planning the activities.

32. Slope • It controls the rainfall distribution and movement, land utilization and watershed behavior. Climate • Climate is a determining factor for the management of all aspects of watershed. Drainage • The order ,pattern and density of drainage have a importance influence on watershed. Land use • Land use pattern is vital for watershed development. • It helps for planning, programming and implementing a management project on a watershed.

33. Vegetation • Detailed information on vegetation cover helps in choosing type, mode and manner of greening the watershed. Geology & soils • Rocks and soils, together influence water storage, movement and infiltration. Hydrogeology • It provides the information about ground water availability in the context of conjunctive use of surface as well as ground water.

34. Hydrology • Availability, quality and distribution of surface water is basic to the final goal of developing a watershed. Socioeconomics • Statistics on people and their social status,helth,cattel and faiming paractices and share of participation are equally imp in developing a watershed.

35. Watershed development and its objective Objective: • To mitigate the adverse effects of drought on crops and livestock. • To control desertification. • To encourage restoration of ecological balance. • To promote economic development of village community. • To increase the crop yield, to reduce the soil loss, to harvest water resources and to increase the income of farmers.

36. Methods, techniques or steps involved in watershed development • Human resource development • Soil and land management • Water management • Crop management • Afforestation • Rural energy management • Livestock management

37. Human resource development • The NGO staff, village watershed committees and watershed communities have been provided trainings through on field “hands on", structured and farmer to farmer extension. • Soil and land management • Two type in it: • Soil conservation • The soil conservation methods should be adopted in the catchment area. • Land management • If the agricultural land is undulating the water is lost by trapping. • So the agricultural land should be properly levelled to obtain uniform growth of plants with optimum quantity of water. • The steps or land slides in the catchment area should be detected and effective to stabilize them.

39. Crop management • Few crop rotation possible are • Rice –gram • Wheat-millet-gram • Rice-gram-wheat • Method of irrigation • Border- for puddy,wheat,vegetables • Furrow- for cotton,sugurance,potato • Basin - for orchards • Sprinkler- for groundnut, vegetables • Drip - for all type of crops,except paddy

40. Afforetation • Planned growth of plantation and tree plantation in wasted,restricted area is a valued aspect of greening. • It prevent soil erosion. • Rural energy management • This reduces drudgery of rural women. • It mitigates the indoor air pollution. • Livestock management • The livestock population in the watershed comprises cows,bullocks,buffaloes,sheep,goats and camels. • Necessary steps must be taken for their food and health.

41. Water Requirement and conservation : • Planning for the development of water resources is very complex in view of the competing demand for utilization. • water is the most importance resources of a country and of the entire society as a whole since no life is possible without water.

42. Water requirement for different uses

43. Water requirement for municipal supplies • Required by the public for various, domestic, industrial, Commercial uses and public utility purposes fire demand water losses etc. • Besides the average consumptions the peek demands are also worked out while designing public water supplies.

45. Water requirement for Irrigation • For proper growth and maturity of the crops, water is of vital importance throughout the crop period. • If the natural rain is sufficient and timely so as to satisfy crops requirements, no irrigation water is required for raising these crops. • Generally the seasonal rainfall can’t meet the total water requirement.

47. Water requirement for hydropower Generation • Production of electric power by using the energy of the flowing water is an excellent use of water as no water is consumed in it. • The construction of dam is therefore needed for the generation of this power. • It depend upon the type of area served.

49. Water requirement for navigation : • There should be adequate flow in the river maintain water depth. • Water is released from a storage reservoir to suction downstream flow for navigation. • The reservoir should remain nearly full during the recreation season to permit boating fishing swimming and other water sport.