sustainable water management in rural areas g.m.zuppi dipartimento di scienze ambientali università...

Sustainable Water Management in

Rural Areas

G.M.ZUPPIDipartimento di Scienze AmbientaliUniversità Ca’ Foscari di Venezia

A new concept in environmental and human affairs was introduced with the Brundtland

Declaration of 1987: "Sustainable development is development that meets the needs of the present without compromising

the ability of future generations to meet their own needs." Implicit in this often-

quoted definition is the idea that the natural environment faces stress and

overexploitation and will not be able to indefinitely meet escalating human

demands. Source: www.csa.com/discoveryguides/sustain/overview.php

ECOLOGICAL CATASTROPHE AT THE END OF THE 20TH CENTURYECOLOGICAL CATASTROPHE AT THE END OF THE 20TH CENTURY

If people did not engage in food production (cattle-breeding, agriculture, fishery, etc.) but only collected nature's products like

our ancestors hunters and gatherers, the entire planet would hardly bear several tens of million people without any consequences for the

environment. Source: public.globalnet.hr/~gvlahovi/ekologija/ecological-catastrophe.htm

Uses freshwater in various parts of the world.

Agricultural production accounts for an average of 69 percent of freshwater use worldwide; industry

uses 23 percent and households eight percent.

The dependence of our food production systems

on irrigation links freshwater with food

security, and therefore with human nutrition and

well-being. Source: www.aaas.org/international/ehn/waterpop/desherb.htm

Global water consumption rose sixfold between 1900 and 1995 -

more than double the rate of population

growth - and goes on growing as farming,

industry and domestic demand all increase.

Source: news.bbc.co.uk/1/hi/sci/tech/3747724.stm

Seventy percent of the water used worldwide is used for agriculture.

Much more will be needed if we are to feed the world's growing population - predicted to rise from about six

billion today to 8.9 billion by 2050. And consumption will soar further as more people expect Western-style lifestyles and diets - one kilogram of grain-fed beef needs at least 15 cubic meters of water, while a

kilo of cereals needs only up to three cubic meters.Source: news.bbc.co.uk/1/hi/sci/tech/3747724.stm

Source: ttp://whyfiles.org/131fresh _water/2.html

Sustainable yield is a socio-economic term, not a scientific term. Sustainable yield is usually considered to be that rate of pumping

from wells for which the impact is acceptable; however what impact is “acceptable” is subjective. There will always be a

hydrologic effect of pumping from wells. In this sense, there is no such thing as “safe yield”.

Source: wi.water.usgs.gov/glpf/cn_pmp_src.html

Source: ga.water.usgs.gov/edu/earthgwdecline.html

http://ga.water.usgs.gov/edu/earthgwdecline.html





Over-exploitation Effects

•Ground Subsidence• Groundwater Quality• Saltwater Intrusion

• River-Aquifer Interactions• Wetlands

Overexploitation occurs as far as groundwater abstraction exceeds available groundwater

recharge from precipitation or surface water contribution. In such a case one aquifer or the aquifer system undergo pressure reduction

changing the effective stresses in aquifers (grain to grain stress) and initiating subsidence in fine grained, unconsolidated silt and clay aquifers

(Magara 1978). This may endanger constructions (e.g. Mexico City), move coast lines (e.g.

Maracaibo Lake, Venezuela) and change even the surface drainage system of catchment areas

(Leipzig area, Germany). Source: MAN'S IMPACT ON GROUNDWATER SYSTEMS IAEA, Vienna, VOLUME V

Increase of effective stresses in unconsolidated aquifers due to lowering the hydraulic head.

Source: MAN'S IMPACT ON GROUNDWATER SYSTEMS IAEA, Vienna, VOLUME V

Subsidence of sediments reduces the storage capacity of aquifers. If overexploitation finishes,

the reduced porosity will mostly not return to initial conditions, because in unconsolidated rocks plastic deformations dominate over elastic deformations. Therefore, groundwater levels rise after finishing overexploitation often closer to the surface and

changes in coastal lines will never restore to their original position. Thus in some cases a stop of overexploitation after a long run of groundwater

mining might even create hygienic and geotechnical problems.

Source: MAN'S IMPACT ON GROUNDWATER SYSTEMS IAEA, Vienna, VOLUME V

Lake Mexico is gone. On its site are several hundred square kilometers of urban neighborhoods. Lakes Chalco and Xochimilco

are also gone. Only a few canals and small lakes remain. The rest of the area is covered by streets and buildings.

The three northern lakes have also been drained.

Source : a.water.usgs.gov/edu/earthgwlandsubsidew.html

Source: www.salve.it/.../problemi/P-eccezionaliA.htmSource: www.isodarco.it/.../paper/candriai01camuffo.html

Source: www.john-daly.com/ges/msl-rept.htm

http://www.salve.it/.../problemi/P-eccezionaliA.htm

http://www.salve.it/.../problemi/P-eccezionaliA.htm

http://www.john-daly.com/ges/msl-rept.htm





•Ground Subsidence• Groundwater Quality

• Saltwater Intrusion• River-Aquifer Interactions

• Wetlands• Groundwater Quality

Wastewater from the three major water use categories, agriculture, industry, and

domestic use contributes to water pollution. Agricultural fertilizers and pesticides,

industrial effluents, and household wastewaters are often discharged with

minimal treatment into surface water, and sometimes leach into underground aquifers. The contaminated water can be harmful to human health, leading to illness and even

death. Source: www.aaas.org/international/ehn/waterpop/desherb.htm

Over-exploitation of the groundwater quickened the

infiltration of surface water so the groundwater is polluted.

Once it happened it is difficult to recover. Now the

groundwater resource is polluted very severely in

many cities. According to the statistic there are several big

and middle cities whose groundwater is polluted in varied degree and the main pollution source is industry

and living pollution.Source: Foster et al. 1998

Source: www.unep.org/.../water/vitalwater/resources.html

Causes of groundwater contamination: Animal lots

Source: www.montcalm.org/montcalmmold/planningeduc0020.asp

Sea water intrusion

Source: capp.water.usgs.gov/gwa

Seawater intrusion is caused by

decreases in water levels or by rises in seawater

levels. When fresh water is pumped out rapidly, the

height of the freshwater in the

aquifer is lowered, forming

saline wedge Source: www.watersavingtips.org/groundwater.html

Karstification of carbonate rocks in the coastal zones is about 150 m deeper than the recent sea level and the

underground flow path has been opened for the intrusion of specific heavier sea water, on some places very deep in aquifers. Deep karstification is the consequence of the sea

level changes in geologic past.Source: B. Biondic , R. Biondic and H. Meaški , 2005 Geophysical Research Abstracts, Vol. 7, 10567, 2005

Source: : soundwaves.usgs.gov./2001/03/meetings5.html

In the land hydraulic system, when the fresh groundwater is withdrawn by pumping wells at a faster rate than it can be

replenished, a drawdown of the water table occurs with a resulting decrease in the overall hydrostatic

pressure. When this happens near an ocean coastal area, saltwater from the ocean intrudes into the freshwater aquifer

Source: www.engr.uconn.edu/~ lanbo/G229Lect111SWIntru.pdf

The position of the interface between the fresh and saline gw is related to the difference in

density of the two waters.

Source: British Geological Survey. © NERC. UK Groundwater Forum

The Ghyben-Herzberg RelationUnder hydrostatic conditions, the weight of a unit

column of fresh water extending from the water table to the interface is balanced by a unit column of salt water extending from sea level to the same depth as

the point on the interface.

Source: www.solinst.com/Res/papers/101C4Salt.html

Fresh water Salt water

Sea

h

h=constantz

Weight of fresh

water at A= f(h+z)

Weight of sea

water at A= s z

A

Fresh water Salt water

Sea

h

h=constantz

Weight of fresh

water at A= f(h+z)

Weight of sea

water at A= s z

A

z = 40h

The Ghyben-Herzberg analysis assumes hydrostatic conditions in a homogeneous,

unconfined coastal aquifer. According to this relation, if the water table in an unconfined

coastal aquifer is lowered by 1 m, the saltwater interface will rise 40 m.

The salt water rises 10.6 m for every 0,30

m of freshwater depression and forms a

cone of ascension. Intrusion can affect the

quality of water not only at the pumping well sites, but also at other well sites, and

undeveloped portions of the aquifer.

Sources: pubs.usgs.gov/fs/2000/fs-057-00/pdf/fs05700.pdf; www.lenntech.com/groundwater/seawater-intrusions.htm

Since the early 1960's, the coastal aquifers of China have

been studied for salt-water intrusion. With a transition

zone of 1.5 to 6.0 km, and an aquifer area of more than 580 km2, the increasing extension of the salt-water intrusion is a

major concern in this area. Throughout the transition

zone, mixing of local fresh water, sea water, and cation exchange can be recognized. In the City of Laizhou and in

the City of Longkou salt-water intrusion had been

caused by excessive pumping of the groundwater in these

areas. Source:

www.solinst.com/Res/papers/101C4Salt.html

In the beginning the observations were taken

from some specific, isolated spots (0.5 km2). Eventually the intrusion area spread as increases persisted in agriculture and industry. intrusion.In 1979, the salt-water

intrusion area covered 16 km2; 39 km2 in 1982; 71

km2 in 1984; and 196 km2 in 1987. By 1989, the salt-water intrusion

area became a continuous zone covering an area of

238 km2 in Laizhou. Source:

www.solinst.com/Res/papers/101C4Salt.html

In the 1970's, the salt-water intrusion

area in the SW of the

area increased by 4 km2 each year. In the

early 1980's, this number increased to 11.1 km2,

and after the mid-1980's to 30 km2.

Source: www.solinst.com/Res/papers/101C4Salt.ht

ml

Aquifers can exert a strong influence on river flows. In summer, many rivers are dependent on the groundwater base

flow contribution for their minimum flow. Lower groundwater levels due to over-exploitation may, therefore, endanger

riverdependent ecological and economic functions, including surface water abstractions, dilution of effluents, navigation

and hydropower generation.Source: www.grid.unep.ch/product/publication/freshwater_europe/ecosys.php

Source: capp.water.usgs.gov/gwa/ch_f/gif/F030.GIF

Lake Chad: A conspiracy of climate change and crops

Straddling the borders of Chad, Niger and Cameroonin West Africa, Lake Chad has been a source of

freshwater for irrigation projects in all these countries.Maps drawn from a series of satellite images show a

dramatic decrease in the size of the lake over the past30 years. Since 1963, the lake has shrunk to nearly a

twentieth of its original size, due both to climaticchanges and to high demands for agricultural water.

Since 1963, the surface area of Lake Chad hasdecreased from approximately 25 000 km2 to 1 350

km2 (Scientific American, 2001).

Dry spell: Lake Chad photographed in 1972 (left) and in 1987

Source: img.dailymail.co.uk


Photo W.M.Edmunds


Between June 1966 and January 1973, the surface area of Lake Chad shrunk from 22 772 km2 to 15 400 km2.

•In 1982, the lake's surface area was estimated to be about 2 276 km2 . In February 1994, Meteosat images were used to measure it at just 1 756 km2 .•Between 1953 and 1979, irrigation had only a modest impact on the Lake Chad ecosystem. Between 1983 and 1994, however, irrigation water use increased four-fold.

Source: http://www.unep.org/dewa/assessments/ecosystems/water/vitalwater/27.htm


•About 50% of the decrease in the lake's size since the 1960s is attributed to human water use, with the remainder attributed to shifting climate patterns.•Invasive plant species currently cover about 50% of the remaining surface of Lake Chad.

Source: http://www.unep.org/dewa/assessments/ecosystems/water/vitalwater/27.htm

Global climatic change and the Aral Sea basin.

Source .www.gly.uga.edu/railsback/CTW/AralSea.jpeg

Lake Aral: A conspiracy of climate change and anthropic activities

The Aral Sea Basin is considered a disaster zone. Demands on the watershed for irrigation and other purposes have overdrawn water resources. By 1991 almost all river water was being diverted for irrigation and the sea had lost half its area. What flowed in was salt-laden, gradually killing most fish. Wetlands dried up in river deltas. Game, birds, and other wildlife have become rarer. Windstorms carrying sand and dried salt into the air have increased in frequency and severity.

Source: www.gefweb.org

Lake Aral: A conspiracy of climate change and anthropic activities

The impact on local communities and economies has been severe, bringing widespread unemployment and poverty as fisheries, game habitat, pastures, and agricultural land have lost productivity. Public water supplies have become unreliable and unsafe due to bacterial contamination. The high incidence of other diseases has led to speculation on environmental causes. Land upstream of the lake has been damaged from excess water withdrawals, leading to flooding and salinization of the land. If trends continue, most agricultural land in these river basins will be unfit for agriculture within a few decades.

Source: www.gefweb.org

Large dams are a major part of the water-population equation. Dams are most often

constructed for hydroelectricity, but they are also used to divert water for irrigation or

domestic water supplies and to control flooding. Worldwide, there are some 40,000 large dams (those higher than 15 meters),

most of which were built since 1950. A direct demographic impact of dam building has been the displacement of an estimated 30 million to 60 million people by reservoirs and irrigation

works.

Source: www.aaas.org

In some cases, dams can also attract migration, particularly if the water is channelled to arid

areas or if industries relocate to make use of the resulting hydropower. Although dams

contribute to increased agricultural production and economic growth, they can also adversely affect fisheries and aquatic ecosystems (e.g., rivers, floodplains, deltas, and mangroves).

Disruptions in natural flood cycles can disproportionately affect the rural poor, whose livelihoods often depend on wetlands, fisheries,

and flood-dependent agriculture. If aquatic ecosystems are altered, these rural residents may

be forced to migrate to other areas. Source: www.aaas.org

Water and population dynamics

Population dynamics affect water resources, but the relationship also works in the other

direction. The India case study illustrates that in rural areas of Karnataka State, population growth

has contributed to increased demands for water, expanded drilling of boreholes (tube

wells), and resulting depletion of groundwater resources and water scarcity. At the same time, water scarcity has stimulated rapid emigration

to urban areas.

Source: www..aaas.org

The relationship is heavily influenced by the local climate, topography, vegetation, geology,

and degree of human alteration of the landscape. Socioeconomic conditions, culture,

institutional arrangements, and political factors also play major roles. Thus, there are

no blanket prescriptions that will lead to more sustainable water-population relationships in,

for example, Guatemalans PetÈn region (lowlands and jungle) or the Kafue Flats of

Zambia.




It transcends national boundaries. River basins do not always respect national

boundaries. Use of water upstream, which is closely related to population dynamics

and economic development, affects countries downstream. Likewise,

downstream dams can block fish from migrating upstream.



It transcends national boundaries.

In the Ganges River Basin, deforestation and water abstraction in Nepal and India have reduced river flows and caused dry-season water shortages, salinization, and fishery

depletion in Bangladesh. People living in the Ganges delta have been adversely affected by

such changes.


It varies over time. In Mali, Morocco, and Jordan, cyclical patterns of drought greatly affect water resources from year to year. The population carrying capacity for these countries

may be influenced more by the periodic droughts than by average annual rainfall over a 20 to 30 year period




It varies over time. In India and Bangladesh, water availability is dramatically affected by

seasonal change, such as the onset of monsoon season. Populations must adapt to these changes

accordingly.


Source: www.pacificislandtravel.com/.../monsoons4.


A better understanding of the relationship between population

dynamics and water resources is a first step toward designing policies that can

make these relationships more sustainable.


Policies should:

•take into account potential reciprocal impacts and responses;•be sensitive to local contexts, draw on multidisciplinary knowledge, and employ multisectoral strategies in problem analysis, policymaking, project design, implementation, monitoring, and evaluation;•account for upstream and downstream effects and the shared nature of water resources; •use adaptive management that is flexible enough to adjust to the changing nature of water and population relationships over time.


Water scarcity combined with over-exploitation of the available resources threatens Chinese sustainable development. Rapid economic growth has led to over-commitment of available surface water resources, overdraft of groundwater resources in many areas

www.wrdmap.com

With 51 million hectares of irrigated land, China has more than any other country. This compares with

some 46 million hectares in India and 20 million in the United States, the countries ranking second and third

in irrigated area. Irrigated surfaces grew by 34 million ha from the 17 million ha since 1950. Far

more important to China than to those two nations, irrigation covers roughly half of the total cropland area and accounts for nearly four-fifths of the all-important grain harvest. Located in the Northern

China plain, the basins of the rivers Huang, Hai and Huai (3H basin) account for about 44% of corn, 67%

of wheat, 72% of millet, 40% of cotton and 24% of vegetable oil productions.

Source: www.cybergeo.eu/index4141.html

Irrigation in the 3H basin is relying on a growing number of deeper and deeper tube wells, so as to

pump into aquifers. The global level of the water table fell by 1,5 meter per year between 1993 and 1998,

according to a study by the Agriculture University of Beijing. With most aquifers being depleted, China is

now reconsidering its options for reestablishing a balance between water use and supply, since the destruction of these very aquifers would bring a

severe blow to agriculture in this region, given its dependence on groundwater.


Source: www.mwr.gov.cn/english1/20060110/2006011010410X

XDENTE.pdf

There is water enough in China on a national scale: about 2 260 m³/person/year on

average in 1999. But this water is very unevenly

distributed: water available figures up to 32

000 m³/person/year in the coastal South-East,

whereas the North China Plain receives

only 225 m³/person/year.


The only solution, according to Chinese planners, apart from drastic measures to cut down on rural

water use, or massive and costly investment

in water-efficient irrigation techniques, is diversion of water from elsewhere. The

diversion of the Yangzi waters has

been debated among Chinese planners

since 1952 Source: www.cybergeo.eu/index4141.html

The large inter-basin water transfers partially solves the problem of Water scarcity

Water resources are unevenly distributed in China with great differences from south to north. Water resources are

rich in the south while insufficient in the north, especially in the Huang-Huai-Hai (Yellow river, Huai river, and Hai

river) Plain.

Over-exploitation of surface water has caused withering of some rivers and lakes, low capacity of flood discharge of

river channels, decrease of flow entering into the sea, increasing siltation of river estuaries and increasingly water disputes between regions, cities or townships. In 1990's, dry-up of the Yellow River occurred very often. In 1997 the dry-

up period of the Yellow River reached to 226 days

Source: www.mwr.gov.cn/english1/20060110/20060110104100XDENTE.pdf

The regional hydrology and ecosystems ofthe Hexi Corridor region of northwestern China

have changed over the last half century under thedriving force of intense human activity and regionalclimate changes. Streamflow issuing from mountainsin the eastern section of the Corridor by way of the

Shiyang River has decreased significantly.

WANG GENXU ; CHENG GUODONG) ; MINGYUAN Du (2003) The impacts of human activity on hydrological processes in the arid

zones of the Hexi Corridor, northwest China, in the past 50 years IAHS-AISH publication ISSN 0144-7815

The region stretches over the territoriesof Qinghain, Gansu, and Inner Mongolia, covering a

total area of 105 km2, including 103 km2 ofplains. Except for the southern

mountain region which receives over 300 mm year,precipitation in most of the region is, on average, less than

200 mm year), with the tail reaches of inland rivers receivingeven less than 50 mm year.

J. Z. Ma, Z. Ding, J. B. Gates, Y. Su (2007) Chloride and the environmental isotopes as the indicators of the groundwater recharge in the Gobi Desert, northwest China. Environmental Geology

The role of agriculture in water scarce areas is a main issue in relation to sustainable water management as irrigation agriculture is the biggest consumer of water.The key orientations in the sector of agriculture in these regions

should be:a) ensuring sustainable rural livelihoods and halting the rural

exodusb) developing rural human resources and ensuring gender-

sensitive policies and institutionsc) enhancing sustainable natural resources management and

preparing to adapt to climate change impacts on the rural environment; consequently, one of the priorities must be the

management of water resources.d) contributing to regional food security goals

Source: www.mio-ecsde.org/staticpages/index.php?page=agriculture

It may be considered as a type area for

much of northern China

where in modern times an arid belt

lies at the northern limit of the area reached

by the SE monsoon.

Ma, J.Z., Wang, X.S. and Edmunds, W M. (2005) The characteristics of groundwater resources and their changes under the impacts of human activity in

the arid north-west China - A case study of the Shiyang river basin. J. Arid Environments, 61: 277-295.

To the east this region is fed by the Yellow River, which then passes through the Gobi Desert. River

water has been used to alleviate water

shortage, although withdrawals have

increased significantly and grossly reduced its

flow recently. J. Z. Ma, Z. Ding, J. B. Gates, Y. Su (2007) Chloride and the environmental isotopes as the indicators of the groundwater recharge in the Gobi Desert,

northwest China. Environmental Geology

Groundwater withdrawals have increased significantly and river grossly reduced its flow in recent years. The lake progressively

diminished in size splitting into two smaller lakes

around the first century AD due to upstream

abstraction. This process continued over the last two millennia with the complete disappearance of the lake

by the mid 1950s Water level decline in Well No 94 (up to 1m per year)

Minqin Basin

Ma, J.Z., Wang, X.S. and Edmunds, W M. (2005) The characteristics of groundwater resources and their changes under the impacts of human activity in the arid north-west China - A case study of the Shiyang river basin. J. Arid Environments, 61: 277-295.

Minqin Basin

With potential evaporation estimates of

approximately 2600 mm/yr, mass-balance

considerations clearly indicate that

direct recharge is not sufficient to supply

the desert lakes, and that additional

recharge sources would be required to

do so. Ma, J.Z., Wang, X.S. and Edmunds, W M. (2005) The characteristics of groundwater resources and their changes under the impacts of

human activity in the arid north-west China - A case study of the Shiyang river basin. J. Arid Environments, 61: 277-295.

The only nearby major sources of water are

down-gradient from the desert interior (i.e.

Guezi Hu Wetland and the Heihe River). The

Yabulai and Longshou mountain ranges could

possibly supply mountain-front or

mountain-block recharge, but under

current climatic conditions this would not likely be able to

sustain flow volumes implied by the lakes.

Minqin Basin

J. Z. Ma, Z. Ding, J. B. Gates, Y. Su (2007) Chloride and the environmental isotopes as the indicators of the groundwater recharge in the Gobi Desert, northwest China. Environmental

Geology

The oasis Minqin Oasis fed by the lower reach of the Shiyang River and sustained by a shallow

regional water table, is the ancestral homeland for thousands of farmers, supporting a variety of crops,

from cotton to sunflower

(A) Location of Shiyang River drainage in arid China. The north boundary of the present Asian summer monsoon is shown by dotted line (revised from Gao et al., 1962). Black

filled circles and numbers 1–3 mark the locations of Bangong Co, Qinghai Lake and Lake Daihai. (B) The Shiyang River drainage and location of the terminal lake area inserted.

Dashed line is former Shiyang river channel, named Daxihe River in history.Dotted area is covered by dune sand; the shaded area is Qilian Mts. (C) TADEM image map, showing topography of the terminal area. The desiccated lake basins closed by solid lines are a-L.

Xixiaochi, b-L. Dongxiaochi, c-L. Yema, d-L. Dongping, e-L. Sanjiaocheng, f-L. Xijian, g-L. Mawangmiao and h-L. Baijian. The triangles and the capital letters mark the investigated

sections (see Fig. 2). The lowest pass of the closed basin is marked by the arrow; the

division between the eastern and western parts of the terminal lake by the dashed line. ,

Qi Shi, Fa-Hu Chen, Yan Zhu, David Madsen, 2002 Lake evolution of the terminal area of Shiyang River drainage in arid China since the last glaciation. Quaternary International

Qi Shi, Fa-Hu Chen, Yan Zhu, David Madsen, 2002 Lake evolution of the terminal area of Shiyang River drainage in arid China since the last glaciation. Quaternary InternationalMa, J., Ding, L., Jiawu, Z., Edmunds, W.M. and Prudhomme, C., 2003. Groundwater recharge and climatic change during the last 1000 years from unsaturated zone of SE Badain Jaran Desert. Chinese Science Bulletin,

An abandoned house in Minqin, where the harsh environmental conditions have prompted many

families to move away. Many villages on the northern reaches of Minqin, right on the deserts' edge, are partially abandoned or totally empty.

North: water resources concentrated in theNorth: water resources concentrated in the Amazon BasinAmazon Basin

68 %68 %

Northeast: poorest and driest Northeast: poorest and driest 3%3%

South-Southeast: urban and industrial South-Southeast: urban and industrial pollutionpollution

13%13%

Mid West: the new agricultural frontierMid West: the new agricultural frontier16%16%

Brazil

US$ 14.450 billion

23% Water Supply77% Wastewater

Source: www.ana.gov.br/.../Water%20for%20the%20%20Brazilian%20Development_Stockholm%202005%20B.Braga.pps

dalcanale

inserir numeros absolutos

The Brazilian Semi-Arid region The Brazilian Semi-Arid region encompasses 86% of the encompasses 86% of the territory of the NE States, the territory of the NE States, the northern part of Minas Gerais northern part of Minas Gerais (11%) and Espírito Santo (2,5%) (11%) and Espírito Santo (2,5%) with a total area of 974.752 Kmwith a total area of 974.752 Km22..

Average annual rainfall is Average annual rainfall is 750mm to as low as 400 mm in 750mm to as low as 400 mm in some localities;some localities;

Estimated annual potential Estimated annual potential evapotranspiration is 2,500mmevapotranspiration is 2,500mm.


• • CONCEPTCONCEPT: centered on emergency and focusing on : centered on emergency and focusing on drought “combat”;drought “combat”;

ANTECEDENT CONDITIONSANTECEDENT CONDITIONSANTECEDENT CONDITIONSANTECEDENT CONDITIONS

• • INSTRUMENTSINSTRUMENTS: work forces, food and water stamps + : work forces, food and water stamps + water infrastructure without management;water infrastructure without management;• • INSTRUMENTSINSTRUMENTS: work forces, food and water stamps + : work forces, food and water stamps + water infrastructure without management;water infrastructure without management;

• • PROBLEMSPROBLEMS: local politics interference, maintenance : local politics interference, maintenance of high deficits, no preparedness for the next drought of high deficits, no preparedness for the next drought and high public investmentsand high public investments

• • PROBLEMSPROBLEMS: local politics interference, maintenance : local politics interference, maintenance of high deficits, no preparedness for the next drought of high deficits, no preparedness for the next drought and high public investmentsand high public investments


• Objective

– Provide sustainable water supply to the semi-arid NE region of Brazil

• Concept

– Competitive and decentralized program among semi-arid States

– Combination of water infrastructure and institutional development


• Implementation

– Annual action program submitted by States is approved by Steering Committee

– Feasibility analysis of Infrastructure (pipelines, canals, dams and reservoirs) based on detailed consideration of technical, economic and environmental dimensions

– Steering Committee - Ministry of Environment – ANA and Ministry of National Integration (infrastructure development)


UNDERGROUND DAMS


São Francisco Interbasin Water Transfer Project


CONCLUSIONS

Environmental concerns must be part of modernization in water use and management. Extraction from rivers and lakes and the construction of irrigation infrastructure invariably

displaces natural wetlands which are, themselves, highly productive components of agro-ecological systems. Drainage

from irrigation often results in loss of water quality, the spread of water-related diseases and soil degradation through

waterlogging and salinization. To reduce these impacts modern water management needs to be based on strategic

environmental assessments and cost-benefit analysis, constant environmental monitoring and integration of irrigation into

the wider environmental context. Source:www.fao.org/ag/magazine/0303sp1.htm

CONCLUSIONS-2

But there also needs to be wider recognition that sound water management produces positive results, including the socio-

economic viability of entire rural areas, through development of the social capital required to manage irrigation systems and the

expansion of transport and marketing infrastructure to sell agricultural produce. Positive environmental effects of irrigation include the creation of artificial wetland systems, micro-climates

and associated biodiversity. Land management for rain-fed agriculture helps control soil erosion and protect downstream

areas from floods. "Recognizing the diversity and the amplitude of these externalities is fundamental to sustainable development," FAO says. Conversely, management focused solely on crops will

become unsustainable in economic and environmental terms.Source: www.fao.org/ag/magazine/0303sp1.htm

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