1. Introduction - 2015.6

Chapter 1 Introduction

Water Resources Planning

and Management

Chapter 1 Introduction

Concepts of Water resources Characteristics of Water resources Water problems Water resources management

Contents

As well as we know, tremendous volumes of water are present on our planet. It has been estimated that if the entire surface of the earth were leveled off and the land areas filled into the ocean depths, we would have a whole planet covered with water to a depth of 10,000 ft.

Can we say, all the water on the earth may be thought of water resources?

Water resources refers generally to the part of water with the following characteristics: useful or potentially useful to human beings and society both in quantity and quality; can be renewed during a certain period. Water resources is a dynamic resource.

Water uses include agricultural, industrial, household, recreational and environmental activities. The majority of human uses require fresh water.

It can exist easily in all three statessolid, liquid, and gaseous. 97% of the water on the Earth is salt water and only 3% is fresh water;

slightly over 2/3 of the fresh water is frozen in glaciers and polar ice caps. The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction is above ground or in the air.

1.1 Water resources

1.1 Water resources

This is a graphical distribution of water on the Earth. Only 3% of the Earth's water is fresh water. Most of it in ice caps and glaciers (69%) and groundwater (30%), while all lakes, rivers and swamps only account for a small fraction (0.3%) of the Earth's total freshwater.

1.1 Water resources Sources of fresh water

(1) Surface water

Surface water refers to water in a river, lake or fresh water wetland. Surface water is mainly replenished by precipitation and naturally lost through discharge to the oceans, evaporation, evapotranspiration and sub-surface seepage.

Although the natural input to surface water system is precipitation within its watershed, the total quantity of water in that system at any given time is also dependent on many other factors. These factors include storage capacity in lakes, wetlands and artificial reservoirs, the permeability of the soil beneath these storage bodies, the runoff characteristics of the land in the watershed, the timing of the precipitation and local evaporation rates. All of these factors also affect the proportions of water loss.

1.1 Water resources

Sources of fresh water(1) Surface water

Human activities can have a large and sometimes devastating impact on these factors. Humans often increase storage capacity by constructing reservoirs and decrease it by draining wetlands. Humans often increase runoff quantities and velocities by paving areas and channelizing stream flow.

The total quantity of available water at any given time is an important consideration. Some human water users have an intermittent need for water. For example, many farms require large quantities of water in the spring, and no water at all in the winter. To supply such a farm with water, a surface water system may require a large storage capacity to collect water throughout the year and release it in a short period of time. Other users have a continuous need for water, such as a power plant that requires water for cooling. To supply such a power plant with water, a surface water system only needs enough storage capacity to fill in when average stream flow is below the power plant's need.

1.1 Water resources

Sources of fresh water(2) Ground water

Sub-surface water, or groundwater, is fresh water located in the pore space of soil and rocks. It is also water that is flowing within aquifers below the water table. Sometimes it is useful to make a distinction between sub-surface water that is closely associated with surface water and deep sub-surface water in an aquifer (sometimes called "fossil water").

Sub-surface water can be thought of in the same terms as surface water: inputs, outputs and storage. The critical difference is that due to its slow rate of turnover, sub-surface water storage is generally much larger compared to inputs than it is for surface water. This difference makes it easy for humans to use sub-surface water unsustainably for a long time without severe consequences. Nevertheless, over the long term the average rate of seepage above a sub-surface water source is the upper bound for average consumption of water from that source.

1.1 Water resources Sources of fresh water

(2) Ground water

The natural input to sub-surface water is seepage from surface water. The natural outputs from sub-surface water are springs and seepage to the rivers.

If the surface water source is also subject to substantial evaporation, a sub-surface water source may become saline. This situation can occur naturally under endorheic bodies of water, or artificially under irrigated farmland. In coastal areas, human use of a sub-surface water source may cause the direction of seepage to ocean to reverse which can also cause soil salinization. Humans can also cause sub-surface water to be "lost" (i.e. become unusable) through pollution. Humans can increase the input to a sub-surface water source by building reservoirs or detention ponds.

1.1 Water resources Sources of fresh water(3) Frozen water

Glacier runoff is considered to be surface water. Several schemes have been proposed to make use of icebergs as a water source, however this has only been done for novelty purposes.

The Himalayas, which are often called "The Roof of the World", containsome of the most extensive and rough high altitude areas on Earth as well as the greatest area of glaciers and permafrost outside of the poles. Ten of Asias largest rivers flow from there, and more than a billion peoples livelihoods depend on them. To complicate matters, temperatures are rising more rapidly here than the global average. In Nepal the temperature has risen by 0.6 degrees Celsius over the last decade, whereas globally, the Earth has warmed approximately 0.7 degrees Celsius over the last hundred years.

Iceberg near Newfoundland

1.1 Water resources

Desalination

Desalination is an artificial process by

which saline water (generally sea water)

is converted to fresh water. The most

common desalination processes are

distillation and reverse osmosis.

Desalination is currently expensive compared to most alternative sources of

water, and only a very small fraction of total human use is supplied by

desalination. It is only economically practical for high-valued uses (such as

household and industrial uses) in arid areas. The most extensive use is in the

Persian Gulf.

1.1 Water resourcesClassification of water resources

Surface water Ground water Soil water

Meteoric water Biological water

Classification

phreatic water confined water

river lake glacier

1.2 Characteristics of Water resources(1) Cyclicity of hydrologic cycle and limitation of water resources The hydrologic cycle contains four principal terms precipitation, evapotranspiration, infiltration, and water runoff. Water seems inexhaustible due to water cycle.

Although the update cycle of some fresh water is short, the available water resources is limited because of water pollution,and the expensive cost of water treatment.

1.2 Characteristics of Water resources

(2) Uneven spatial and timely distribution of volume

Most of us are fortunate to be surrounded by fairly available supplies of water in various forms. Water vapor is present even in the atmosphere of the deserts and it is certainly present in the humid air of tropical and subtropical climates. Water is stored in lakes, ponds, reservoirs, rivers, and streams on the surface of the earth as well as in the great ocean areas of the world. It is also stored in less visible form in the vegetation of the surface and, although many of us may not see them, in the glaciers and ice caps of the polar or high-altitude regions of the world. Finally, water is stored in the upper soil layers to be utilized by plant roots as well as in the deeper soil and rock layers as part of the groundwater.


(2) Uneven spatial and timely distribution of volume

As well as we know, tremendous volumes of water are present on our planet. It has been estimated that if the entire surface of the earth were leveled off and the land areas filled into the ocean depths, we would have a whole planet covered with water to a depth of 10,000 ft. But, the distribution of water varies greatly. Some portions of the country are richly endowed and other portions are practically bereft of water. While overall supplies are sufficient, certain areas have considerably more than others.


1Incl. Iceland.2Excl. Canadian Archipelago and including Centtral America.3Incl. Tasmania, New Guinea and New Zealand. For New Guinea,Aitken et al. (1972)estimate precipitation at 3150 mm and total runoff at 2110mm.4Excl. Antarctica,Greenland and Canadian Archipelago. USSR:Union of Soviet Socialist Republics

Data source: statistics from the United Nations in 2013

Uneven spatial distribution of volume

Classified in accordance with annual mean precipitation, five different regions, i.e, more rain, humid, semi-humid, semi-arid, arid, can be subdivided, corresponding to abundant water, more water, intermediate, less water, and arid region, if classified in accordance with annual runoff.


The criteria of these classifications are given in Table1. Usingan annual mean precipitation of 400 mm as a demarcation, 45% of the national territory belongs to arid or semi-arid regions.

Uneven spatial distribution of volume


1.2 Water resources distribution

Uneven spatial distribution of volumeClassified in accordance with annual mean precipitation, five different regions, i.e, more rain, humid, semi-humid, semi-arid, arid, can be subdivided, corresponding to abundant water, more water, intermediate, less water, and arid region, if classified in accordance with annual runoff.

Water resources of water zones in China in 2013

Data sources: Water resources bulletin of China in 2013

Uneven spatial distribution of volume1.2 Characteristics of Water resources

Per capita water resources all over the country


Uneven timely distribution of volume Uneven seasonal as well as yearly distribution of annual precipitation exist. Consecutive dry years or wet years occurred in the past. In most areas of China, rainfall is scarce in winter and spring, abundant in summer and autumn. Most part of the annual precipitation is concentrated in summer, appearing in the form of storms.

In the south-eastern provinces together with the north-western part of Xinjiang Autonomous Region, plenty rainfall takes place in the period ofMarch-June, April-July, or May-August with about 50%-60% of the normal annual precipitation.

In the north-eastern, north, north-western and south-western regions of China, precipitation amounting to 70%-80% of the normal annualprecipitation concentrates in June-September.

In the middle and lower reaches of the Yellow River and in the drainage basins of the Hai River and the Huai River, most of the rainfall focus in the two mouths of July and August.


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Significant yearly variation in precipitation in China exists most commonly in the north, with alternate of consecutive dry years or wet years.

According to 258 years data of precipitation in Beijing, annual precipitation in the wettest year (year 1959, 1406 mm) is 5.8 times that of the driest year (year 1869, 242 mm).

In the recent 60 years, the Yellow River has 11 consecutive years of dry (1922 -1932) and 9 consecutive wet years (1943-1951).

In the recent 69 years, the Songhua River has 11 (1898-1908) and 13 (1916-1928) consecutive dry years and 7 consecutive wet years (1960-1966) .

The seasonal and yearly variation of precipitation and runoff ismore apparently in the north than in the south, and is most noticeable in areas lacking water resources.

Uneven timely distribution of volume1.2 Characteristics of Water resources

(3) Multi-purposes

purpose

Domestic water

Production water

Ecological water

urban domestic water

rural domestic water

primary industry

secondary industry

tertiary industry


Data source: Water resources bulletin of Jiangsu Province in 2013


The total water consumption of Jiangsu Province is 49.89 billion m3, among which:

the production water accounts for 92.3% of the total water;; domestic water accounts for 7.1%; environmental: 0.6%.

According to the division of industrial structure, the primary industry water accounts for 65.6%; secondary industry water 31.4%, the tertiary industry water 3.0%.

(4) both advantages and disadvantages

Benefits: water supply for households; electricity generation shipping breed aquatics industrial and agricultural production, etc.

Harms: floods; droughts soil erosion; water pollution, etc.


1.3 Water problems

It is hardly necessary to state that water is one of the most important minerals and vital for all life. It has played an important role in the past and it will play the central role in the well-being and development of our society in the future. This most precious resource is sometimes scarce, sometimes plentiful and always very unevenly distributed, both in space and time, and these characteristics may cause some problems.

Therefore, this part we will learn something about water problems, especially in China.

1.3 Water problems1. Water scarcity

Water scarcity is the lack of sufficient available water resources to meet the demands of water usage in a region. It already affects every continent and around 2.8 billion people around the world at least one month out of every year. More than 1.2 billion people lack access to clean drinking water.

1.3 Water problems1. Water scarcity

Water scarcity can be a result of two mechanisms: physical (absolute) water scarcity and economic water scarcity, where physical water scarcity is a result of inadequate natural water resources to supply a region's demand, and economic water scarcity is a result of poor management of the sufficient available water resources. According to the United Nations Development Programme, the latter is found more often to be the cause of countries or regions experiencing water scarcity, as most countries or regions have enough water to meet household, industrial, agricultural, and environmental needs, but lack the means to provide it in an accessible manner.

The reduction of water scarcity is a goal of many countries and governments. The UN recognizes the importance of reducing the number of people without sustainable access to clean water and sanitation. The Millennium Development Goals within the United Nations Millennium Declaration state that by 2015 they resolve to "halve the proportion of people who are unable to reach or to afford safe drinking water."

Water scarcity involves water stress, water shortage or deficits, and water crisis.The concept of water stress is the difficulty of obtaining sources of fresh water for use during a period of time and may result infurther depletion and deterioration of available water resources.

Water shortages may be caused by climate change, such as altered weather patterns including droughts or floods, increased pollution, and increased human demand and overuse of water.

A water crisis is a situation where the available potable, unpolluted water within a region is less than that region's demand.

Water scarcity is being driven by two converging phenomena: growing freshwater use and depletion of usable freshwater resources.

1.3 Water problems

1.3 Water problems

1Water stress The United Nations (UN) estimates that, of 1.4 billion cubic kilometers (1

quadrillion acre-feet) of water on Earth, just 200,000 cubic kilometers (162.1 billion acre-feet) represent fresh water available for human consumption.

More than one in every six people in the world is water stressed, meaning that they do not have access to potable water. Those that are water stressed make up 1.1 billion people in the world and are living in developing countries.

According to the Falkenmark Water Stress Indicator,(1) a country or region is said to experience "water stress" when annual water

supplies drop below 1,700 cubic metres per person per year.

(2) At levels between 1,700 and 1,000 cubic metres per person per year, periodic or limited water shortages can be expected.

(3) When a country is below 1,000 cubic metres per person per year, the country then faces water crisis . In 2006, about 700 million people in 43 countries were living below the 1,700 cubic metres per person threshold.

1.3 Water problems

1Water stressWater stress is ever intensifying in regions such as China, India, and Sub-Saharan Africa, which contains the largest number of water stressed countries of any region with almost one fourth of the population living in a water stressed country.

The world's most water stressed region is the Middle East with averages of 1,200 cubic metres of water per person. In China, more than 538 million people are living in a water-stressed region. Much of the water stressed population currently live in river basins where the usage of water resources greatly exceed the renewal of the water source.

1.3 Water problems2Water shortage The annual renewable fresh water resources in China is about 2.8 trillion m3, but the per capita is only a quarter to one fifth of the world average and China is one of the world's 13 countries that are short of water resources.

According to the survey, among 669 cities in China, there are more than 400 cities under water shortage and cities that have serious water shortage problems account for 32%.

There is serious shortage of water resources in coastal regions, among the 56 coastal cities, 18 are extremely short of water, 10 are severely short of water, 9 are moderately short of water and 9 are slightly short of water. Nearly 90% of the cities are exposed to different degree of water shortage.

1.3 Water problemsWater shortage Classification

Resources -shortageIt is caused by the uneven spatial distribution

Poor water Quality

Insufficient Engineering-abilityDue to unbalanced economic development, some areas have little ability to construct water storage projects, which causes water shortage.

Fresh water resources polluted and the water pollution causes the available water resources decreasing.

1.3 Water problems

Drought is an extended time when a region receives a deficiency in its water supply, whether atmospheric, surface or ground water. A drought can last for months or years, or may be declared after as few as 15 days. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region. Although droughts can persist for several years, even a short, intense drought can cause significant damage and harm to the local economy. Annual dry seasons in the tropics significantly increase the chances of a drought developing and subsequent bush fires. Periods of heat can significantly worsen drought conditions by hastening evaporation of water vapor.

2Water shortage

1.3 Water problems

When there is not enough potable water for a given population, the threat of a water crisis is realized. The United Nations and other world organizations consider a variety of regions to have water crises of global concern. Other organizations, such as the Food and Agriculture Organization, argue that there are no water crises in such places, but steps must still be taken to avoid one.

3Water crisis

principal manifestations Inadequate access to safe drinking water;

Inadequate access to sanitation which often leads to water pollution Groundwater over exploitation (excessive use) leading to diminished agricultural yields Overuse and pollution of water resources harming biodiversity Regional conflicts over scarce water resources sometimes resulting in warfare

1.3 Water problems

A flood is an overflow of water that submerges land which is usually dry. The European Union (EU) Floods Directive defines a flood as a covering by water of land not normally covered by water. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Flooding may occur as an overflow of water from water bodies, such as a river or lake, in which the water overtops or breaks levees, resulting in some of that water escaping its usual boundaries, or it may occur due to an accumulation of rainwater on saturated ground in an areal flood. While the size of a lake or other body of water will vary with seasonal changes in precipitation and snow melt, these changes in size are unlikely to be considered significant unless they flood property or drown domestic animals.

2. Flood

1.3 Water problems

Floods can also occur in rivers when the flow rate exceeds the capacity of the river channel, particularly at bends or meanders in the waterway. Floods often cause damage to homes and businesses if they are in the natural flood plains of rivers. While riverine flood damage can be eliminated by moving away from rivers and other bodies of water, people have traditionally lived and worked by rivers because the land is usually flat and fertile and because rivers provide easy travel and access to commerce and industry.

Some floods develop slowly, while others such as flash floods, can develop in just a few minutes and without visible signs of rain. Additionally, floods can be local, impacting a neighborhood or community, or very large, affecting entire river basins.

2. Flood

1.3 Water problems

Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds.

Water is typically referred to as polluted when it is impairedby anthropogenic contaminants and either does not support a human use, such as drinking water, or undergoes a marked shift in its ability to support its constituent biotic communities, such as fish. Natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and the ecological status of water.

3. Water pollution

1.3 Water problems

Water pollution affects the entire biosphere plants and organisms living in these bodies of water. In almost all cases the effect is damaging not only to individual species and population, but also to the natural biological communities.

Water pollution is a major global problem which requires ongoing evaluation and revision of water resource policy at all levels (international down to individual aquifers and wells). It has been suggested that water pollution is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily.

3. Water pollution

It is estimated that 580 people in India die of water pollution related illness every day. Around 90% the water in the cities of China is polluted, and as of 2007, half a billion Chinese had no access to safe drinking water.

In addition to the acute problems of water pollution in developing countries, developed countries also continue to struggle with pollution problems. For example, in the most recent national report on water quality in the United States, 45 percent of assessed stream miles, 47% of assessed lake acres, and 32 percent of assessed bays and estuarine square miles were classified as polluted. The head of China's national development agency said in 2007 that one quarter the length of China's seven main rivers were poisoned.

Waterqualityclassification

ClassI :Thewaterisonlysuitableforsourcewaterandnationalnaturereserve

ClassII :Thewaterisonlysuitableforcentralizedsurfacewaterprimaryprotectionzonesfordomesticdrinkingwater,habitatsforrareaquaticorganisms,spawninggroundsforfishandshrimps,feedinggroundsforlarvae,etc

ClassIII:Thewaterisonlysuitableforcentralizedsurfacewatersecondaryprotectionzonesfordomesticdrinkingwater,winteringgroundsforfishandshrimps,migrationchannels,aquacultural groundsandswimmingareas

ClassIV:Thewaterisonlysuitableforindustrialuseandotheramusementpurposesthatdonotinvolvetheliquidcomingintocontactwith skin

ClassV:Thewaterisonlysuitableforagriculturaluseandgenerallandscape

1.3 Water problems

The overall surface water environment of China in 2012 is under mild pollution and major pollution indicators are COD,TP and NH3-N. The ratio of water quality between Class and Class is 51.5% and the ratio of water quality worse than Class accounts for 15.5%.

Water quality classification standard: Environmental Quality Standards for Surface Water GB 3838-2002

3. Water pollution

1.3 Water problems

In 390 sections of about 200 rivers in the 7 major water systems, Class ~ Class , Class ~ Class and worse than Class account for 56.9%, 24.1% and 19.0% respectively.

3. Water pollution

1.3 Water problems

In the 7 major water systemsthe water quality of the Yangtze River and Pearl River is relatively good, the Huai River is slightly polluted, the Yellow River, the Songhua river and Liao River are moderately polluted and the Hai River is severely polluted.

3. Water pollution

1.3 Water problems3. Water pollution

Phenol water pollution in Zhenjiang,Jiangsu Provinces in 2012

Water Pollution in Yancheng,Jiangsu Province,in 2009

Water pollution in Lanzhou section of the Yellow River in 2007

The outbreak of blue green algae in Taihu Lake in 2007

1.3 Water problems

(1) Industry

Emission of wastewater does not meet the standard of discharge; Low processing rates of production.

(2) Agriculture

The extensive use of pesticides; dejecta from the fowls.

(3) Life

Arbitrary waste emissions

3. Water pollution

1.3 Water problems4. low utilization efficiency of Water resources irrigation use

industrial water use

domestic water use

(1) Traditional irrigation mode(2) Low agricultural water use efficiencyThe agricultural water use efficiency in China is about 50%, which is much lower than that in developed countries (70%~80%).

The production technology in some factories is very backward and the repeating utilization factor is low

The equipments of supplying water and delivering water are old so that the phenomenon of water dribbling and leaking is severe.

1.3 Water problems

Causes

a. Lack of water-saving awareness and bad habits of using water;

b. Low water utilization level

Utilization coefficient of irrigation waterChina: 0.51

Western developed country:0.7-0.8

Water quota in each province

Xinjiang :2383m3

Ningxia: 1157m3

Xizang: 1025m3

Tianjin174m3

4. low utilization efficiency of Water resources

1.3 Water problems5. Problems in water resources utilization

The use of water has increased rapidly and significantly over the past few decades around the world. However, increased demand cannot continue indefinitely into the future, although some predictions of future use seem to be based on such an extrapolation. There are many problems in Water resources utilization.

Unreasonable water resources utilizationa. The utilization of industrial water, agricultural water and ecological

water is unreasonable;

b. Water quality pollution: Construction of water conservancy projects in drinking water areas

1.3 Water problemsAnalysis of causes

(1) Low water price

(2) Backward technique

Urban water supply price is lower than the cost of water supply, therefore urban water supply enterprises can only rely on the city government subsidies to maintain water supply management in the case of consecutive years of losses, and their lack of pipe network maintenance and update capabilities result in serious aging of water supply network and water leakage. In addition, the low water resources fee of groundwater may lead to serious exploitation of groundwater in some places and also severely pollute urban groundwater environment.

Backward water use equipments and techniques, which leads to high consumption and low efficiency of water use.


(3) Unreasonable economic structure of three industries

Unreasonable industrial layout and structural contradictions of products Unreasonable three industry structure of China

Three industry structure of China in China


(4) Lack of management

(5) Rapid development of population and economy

The water-saving consciousness of local leaders in some areas, departments and units is not strong; Weak water use management and water supply management; Insufficiency of measures.

The water consumption increases, which exceeds the carrying capacity of water resources.

1.4 Water resources management

The former part describes the ways in which water is found in nature, the volumes of water available for use, as well as trends in the demand for water. It has led to the general conclusion that water resources is not only in short supply but that in certain areas of the world, due to eneven distribution of precipitation or to too great a concentration of people and industry, it is indeed in short supply. As a planet, we will not run out of water although some areas are dangerously close to that condition even now. The problem, then, is not one of insufficient water resources but rather one of water resources management.

Water resources management is required to make use of water reasonably and sustainable. Management is used in its broadest sense. It emphasizes that we must not only focus on the development of water resources but that we must consciously manage water in a way that ensures long-term sustainable use for future generations. The main purpose of water resources management is to meet needs of humans and nature.

1.4 Water resources management

Contents of water resources planning

Arrangementofthecourse

Teaching:teachingSeveralsubjects Introduction Waterresourcesassessment Waterresourcesdemandforecasting Waterresourcessupply&demandbalance ImpactofClimatechangeonwaterresources Waterresourcesmanagement

Homework:3homework Waterresourcesassessment Waterresourcesdemandprediction AvailableWatersupplycalculation

Discussion:PPT Waterproblemsinyourcountryorcity Watersavingtechniques Waterresourcesallocationormanagement Otherrelatedtopicsyouareinterested

Referencebooks

[1]R.J.Liang.EngineeringHydrology.Hohai UniversityPress:NanJing.1991.

[2]LigongLi.Englishofhydraulicandelectricengineering.Hohai UniversityPress:NanJing.1989.

[3]R.QuentinGrafton,KarenHussey.Water ResourcesPlanningandManagement.CambridgeUnicersity Press:NewYork.2011.

[4]JohnR.Mather.WaterResources;distribution,use,andmanagement.NewYork;Toronto:JohnWiley&Snos.1984.

[5]EdwardKuiper.WaterResourcesDevelopment.London:Butterworths.1965.

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1. Introduction - 2015.6

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