Iris prida water cycle and planning

WATER URBANISM AND PL ANNING Towa rd s a n Integ r ate d Water Cycle Manage m ent Research by IRIS PRIDA

a thesis for the

European Postgraduate Masters in Urbanism

UPC Barcelona / TU Delf / KU Leuven / IUA Venezia Promoted by Miquel Corominas December 2015

Water needs during drought periods and imbalances between water demand and available water resources are determining circumstances that may lead to consider water reuse. Water is an essential element for our survival, but how many of its uses are strictly related to human consumption? Could our cities provide lower water quality for non-potable uses? Is it possible to re-use water consumed by the city and achieve the goal of “zero discharge”? Reclaimed water as a new source of supply constitutes an essential component on integrated water resources management, its implementation would represent an strong contribution to nature conservancy and the achievement of a more sustainable water management.

La necesidad de agua en períodos de sequía y desequilibrios entre demanda y recursos hídricos disponibles son circunstancias determinantes que pueden llevar a plantearse la reutilización de agua.

El agua es un elemento indispensable para nuestra superviviencia, pero ¿cuántos de sus usos estan estrictamente relacionados con el consumo humano?, ¿Podrian nuestras ciudades suministrar agua de menor calidad para usos no potables?, ¿Es posible reciclar el agua que consume la ciudad y alcanzar el objetivo de “vertido cero”? La regeneración de aguas, como nueva fuente de suministro, constituye un componente esencial en la gestión integrada de los recursos hídricos, ya que su implantación representaría una fuerte contribución para la preservación de los recursos naturales y el logro de una gestión más sostenible del agua.

From the first moment I saw images from CĂ Mau, a resilient water-based city in south Mekong Delta, a primary thought came up to me: “water is everywhere!â€?. In that moment I realized that I could hardly imagine how daily life was in such remote place.

Apparently, seemed a contradiction that citizens facing periodic monsoon storms had to suffer simultaneously lack of water consequences. This reflection awake on me a large curiosity on water, an essential element, so abundant and so scarce at the same time.

My experience in Vietnam made me also notice how important is an efficient water resources management to citizens quality of life. A promising future for more sustainable and smarter cities would be the consequence, in part, to invest in investigations and promote initiatives related to water cycle management. Therefore, what was an unknown topic to me has become my research subject.

Biosphere water resources are settle in areas with very varied dimensions and locations, from the most evident superficial water bodies flowing through rivers or emerging from natural springs, until large water masses stored into alluvial aquifers. Control over water resources has marked an inflection point in human civilizations development. At the moment when we were able to store water our relations with the territory completely changed. Our ancestors left to move around the territory searching for new resources to handle them for their own benefit and success.Thus, establishing a complex system of mutual interaction for millennia. The introduction of both, agriculture and the need of stable water resources were catalysts for the early fluvial civilizations foundation. The Nile, the Euphrates, the Ganges and Yangtze rivers are still witnesses.

Today, this eternal relationship has little changed, we continue depending on water resources, but little by little we are increasingly aware that our resources are finite and scarce. Cities are densified and require reliable water supply networks that achieve health quality standards. Along with the geographically concentrated water demands, climate models available anticipate greater uncertainty in rainfall and more intense and longer droughts in arid and semi-arid areas.

Due to increased population agricultural sector also grows, and makes it consuming more than two thirds of our water resources. During electric power generation, thermal and nuclear plants consume 80% of total water demand for industrial uses in heat transfers and cooling processes. Water requirements for recreational activities such as golf courses or pools, has also grown during last decades. Facing an un-

certain future referred to water availability, it makes sense to use potable water to irrigate golf courses and to cool turbines?

Water balance is fragile and very easy to break, global temperature increase may trigger large climate changes. We must be aware that water resources original conditions are being dangerously altered causing severe imbalances in our freshwater reservoirs. A continuous increase in global temperature has caused irreversible changes in natural water cycles. Growing demand, aquifers overexploitation, frequent floods periods, prolonged droughts, saline intrusion and sea level rise are some challenges related to water that we will face during next decades.

As I write these words it is being held the United Nations summit in climate change in Paris 2015. It is important that our political representatives will reach an ambitious and strong accord to stop the emission of polluting gases into atmosphere to achieve the objective of “zero emissions” as soon as possible.

Unfortunate social tensions and forced population displacements due to water access difficulties can be avoided with an optimal management of our water resources. Desert regions will be drier and wet areas will increase its average rainfall. Developing countries with economies based on agriculture and livestock will face a situation of exponential growth population and an irremediable depletion of its natural resources, unless we do something to avoid it.

Water demand during drought periods and imbalances between consumption and resources are certainly two of the almost universal circumstances that

lead us to consider the option to recycle water. Water reuse offers important benefits; on the one hand provide a new source of supply, freeing demand on traditional water resources and, on the other hand, allows a better management of wastewater, reducing discharges and approaching to reach the goal of “zero discharges”. It is interesting to realize that many of us already perform an indirect reuse of our water resources: Most of us live downstream; effluents upstream are poured and diluted into the river basins. Then, water will be captured and treated to be drinkable again. Therefore, indirectly our cities are recycling water already.

There are emblematic cases, such as Groundwater Replenishment System (GWRS) in southern California and the city of Windhoek in Namibia for indirect and direct potable water uses, respectively. To ensure local self-sufficiency and reliability of supply, the implementation of initiatives such as California and Namibia has great potential recognition in environmental, technical, economic and social development research.

Water reuse for crop irrigation and gardening has been a priority application in strategies for resources management development. The fact that water consumption in agriculture is much higher than the overall consumption in urban and industrial uses has favored the interest in reclaimed water as a way to have additional (non-conventional) resources, greater reliability, as well as the maintenance of aquatic environments. Catalonia, Spain and states like California spend about 80% of their water resources in agricultural irrigation; considering also the semi-arid nature

of many of these areas and frequent periods of long droughts, it is logical that the interest in non-conventional resources has reached higher levels in these regions. Planned water reuse in Catalonia, as in other areas of Spain, has received considerable attention and development since 1980, although this was not enough to be considered an essential element for an integrated water resources management. However, after almost 20 years of debates, in 2007 the spanish government approved a first regulation (RD 1620/2007) establishing quality standards applicable to reclaimed water for non-potable uses such are: environmental, recreational, industrial, urban and agricultural applications.

Reclaimed water in Barcelona city is already a reality.

The Prat de Llobregat Water Reclamation Plant at southeast of Barcelona, is one of the best examples on water regeneration within and outside european frontiers. Water is a scarce resource throughout Catalan territory due to mediterranean climate irregularities. Water demand is especially high in Barcelona metropolitan area where large part of population, industrial and economic activities are concentrated.

Citizens awareness after repeated drought periods has reached one of the lowest world water consumption rates: 113 liters per person per day. But, it is possible to continue reducing this rate? is it possible to replace non-potable uses with reclaimed water to continue reducing it?

Unfortunately, to reach an integrated water management it is not enough to provide legal and infrastructural instruments, but acceptance and public awareness are fundamental to set up reclaimed water uses

in our daily lives. Citizens information and participation processes are essential to achieve a higher degree of public acceptance around the world.

Reviewing forms and strategies adopted by the earliest fluvial cultures to the construction of the first hydraulic structures in history, like Persian qanats or the complex sewer system built in adobe more than 5,000 years ago in Dholavira, makes realize how important is the presence and the provision of water to ensure the prosperity of a community.

In order to bring closer reclaimed water concept, one of the aims of this research is to clarify in which consist an integrated water cycle management from an urban planner point of view. Explaining widely in which consist advanced water treatments that bring to used-water enough quality standards and costs involved to integrate it into Barcelona city water supply network.

Additionally, it is necessary to contextualize the fragile global water situation and evaluate challenges that we face in the future. Benefits of reclaimed water would help to improve balances between water and an increasing demand in many world areas with freshwater lack.

Finally, a case study: a proposal to transform the current BesĂłs Wastewater Treatment Plant in to a Reclaimed Water Treatment Plant. To built a new water network in orden to supply potable water for non-potable uses in Barcelona innovation district.

The proposal is complemented by a landscape project, a water-based design in Poblenou’s Central Park.

WATER URBANISM AND PLANNING TOWARDS AN INTEGRATED WATER CYCLE MANAGEMENT

1. WATER AND HUMANITY A complex system of mutual interaction .

1.1 1.2

1.3 1.4

2. THE

Mesopotamian and Babylonian Civilizations. Tigris and Euphrates River s 14 Egyptian Civilization. Nile River 15 Southeast Asian Civilizations. Indo and Ganges Rivers 16 Chinese Dynasty. Yellow River 18

WATER CHALLENGE . Facing an uncer tain future

2.1 The impor tance of the Natural Infrastructure Layer 23

2.2 The conflict between the scarcity of water resources and its increasing demand 25

2.3 Climate change and impacts on water supply in Europe 29

3. RECLAIMED WATER. Towards an integrated water cycle management

3.1 Reclaimed water background 33 3.2 How to obtain reclaimed water? 35 · Purification Process (Primar y Treatment) 36 · Advanced Treatments 37 3.3 Current legal context 39

4. INTEGRATED PLANNING. 22@ District, the NewBlue Infrastructure Layer

4.1 A new source of supply to close urban’s water cycle 41 4.2 Hydrological context and requirements 46 4.3 The NewBlue Infrastructure Layer 49 4.4 Poblenou Central Water Park 52

5. CONCLUSIONS

59

Kari Tonseth. Intensive Landscape Urbanism Workshop in Vietnam. March 2014

“Civilization is simply a ser ies of victor ies over nature�

William Har vey

I

WAT E R A N D H U M A N I T Y

A complex system of mutual interaction

Water control is vital to human existence, its presence is key to survival and success of civilizations. The more complex and cramped has been our relationship with water, more it has influenced in our decisions as a community. Control over water changed the way of life of humans transforming radically certain geographical areas around the world.

Predatory occupations, such as hunting and gathering, were gradually replaced by other productive activities such as animal domestication and cultivation of land. Thus, Homo Sapiens societies gradually abandoned nomadism and subsistence economy to become sedentary 13

and producing their own food. Therefore, the establishment of the first settlements were inevitably linked to the presence of water.The most important advantages to settle in a river environment were numerous: water allowed the development of agriculture; the transport of goods through rivers was easier, because the roads were practically nonexistent; the river ensured a constant source of fisheries wich becoming essential for feeding ancient population, the constant flow of rivers cleaned the air carrying pests that could affect the health of its people and it also guaranteed the water supply for a growing population with increasingly complex structures.

W AT E R A N D H U M A N I T Y. A

complex system of mutual interaction

The first civilizations in human history were developed in Mesopotamia, Egypt, India and China around 5,000 years ago. Called Fluvial Civilizations, (Fig.1) they were developed on the banks of major rivers, the Tigris and Euphrates in Mesopotamia; the Nile in Egypt; the Indus in India; and the Yellow River in China.

(4) (1) (3)

The banks of these rivers were occupied by very fertile and easy to irrigate land, prompting the great development of agriculture.

Land was prepared for water retention, some areas were used for crops that after flooding, became fer tile. They continued to lead small watercourses and canals for flooding or intermittent irrigation. Subsequently, regulation and water catchments were added for an optimal exploitation of a larger amount of fer tile land with water shor tages works by management. The consequent economic growth produced major changes; the population increased and what had been small villages grew to become great Civilizations.

With the first settlements and excess of production begins trade between civilizations and thus the emergence of writing and the first transactions of goods. The ancient Persians considered the first letter of its dictionary ab to calling water. The Egyptians used a wavy line ≈ to represent the word water. This derived in the symbol of the Hebrew letter mem, representing mayim or water and eventually the Latin letter M.

(2)

Figure1. Fluvial Civilizations map. (1) Tigris-Euphrates - Mesopotamian and Babylonian Civilizations (3500 BC - 2000 BC) (2) Indus-Ganges - Southeast Asian Civilizations (3000 BC - 150 BC)(3) Nile - Egyptian Civilization (2920 BC - 1100 BC) (4) Yellow River - Shang Dynasty (2000 BC - 1027 BC)

Southwest Asia, Nor th Africa and the Middle East were used.

Qanats (Fig.2) were perhaps the largest hydraulic works of the ancient world, as they allowed the development of communities in places where the water supply was unreliable.

Qanat structure (Fig.3). Was based on digging a main well (or

1.1 Mesopotamian and Babylonian Civilizations.

Tigris and Euphrates Rivers

The first Somalis in East Africa were nomads because of its constant search of water and pasture for their livestock. Between the period of drought and rain, they traveled long distances through the deser t for green pasture. They dug wells by hand and located them at regularly spaced intervals along their routes through the deser t to provide water to their caravans and livestock. This sequence of wells became catalysts for the foundation of great cities born along ancient trade routes. Since 1000 BC, different methods for the utilization of groundwater in different par ts of

14

Figure2. General Schematic for a Qanat. Along the length of a qanat, which can be several kilometers, vertical shafts were sunk at intervals of 20 to 30 meters to remove excavated material and to provide ventilation and access for repairs

W AT E R A N D H U M A N I T Y. A

complex system of mutual interaction

well mother) on a hill, to reach an aquifer. Then an almost horizontal tunnel was built from the base of the hill to the groundwater source. The tunnel should have a minimum slope to allow the water fall. Besides the well mother, secondary wells were dug linking the horizontal tunnel to the surface to ensure ventilation and maintenance. When water debouched, it could be contained or canalized to cultivated land. Today most qanats are in Iran, more than 22,000 that supply water to 75% of the current population.

From the Nile Valley to the Palestine and Syria oasis and the fer tile plains of the Euphrates and the Tigris rivers, a string of cultural centers were spread. Because of its geography, it has been called “Fertile Crescent”. Their governors developed different strategies for flood protection. They built numerous irrigation projects. They adopted laws that ensured the proper maintenance of the irrigation systems. They established taxes to store separatedly water from rain or underground. The main crops were wheat, date palms, figs, grapes, sesame, pomegranates and olive trees. Also raised pigs, donkeys, cattle and goats. All irrigators had to par ticipate in the work of cleaning and maintenance of the canal network. The sands and gravels that were deposited into the canals had to be removed frequently. In addition, they had to minimize contamination of the water, repair the canals after rivers flooding and ensure that water was available to all users. Around 500 BC, it was developed the so-called “rainwater harvesting” which consisted to making the water drain canals to crops or to canalize it through the construction of stone walls ribbed tank to water supply.

1 . 2 E g y p t i a n C i v i l i z a t i o n . Nile River The Nile, one of the longest rivers in the world (6,671 km), is born in the hear t of Africa in the Victoria lake. Located in an area of deser t climate, where rainfall is practically nonexistent, crops were only possible thanks to its natural floods.

Each year, between June and October, the river significantly increases its flow rate due to abundant tropical rains in Sudan

Figure3. The rows of small holes reveal the presence of Qanats systems below the surface: each hole is the top of a ventilation duct

15

W AT E R A N D H U M A N I T Y. A

complex system of mutual interaction

African highlands and late snowmelt in the mountains of central Africa. During this period the river overflows its banks depositing tons of mud and natural fertilizer, called slime or silt. The soil is impregnated with valuable nutrients and humidity enough to turn its banks into an immense and fer tile oasis. The ancient Egyptians could not explain the natural flooding of the river, it is for this reason that they worshiped it as a divinity. The fact that they built leeves and irrigation canals enabled the Egyptians to protect themselves from lack and excess of water that the river caused as well as making possible the exploitation of the Nile Valley, source of life and prosperity throughout three millennia.

Figure4. Egyptian Shadoof

In addition, different devices were used by Egyptian civilization, an extensive system of canals and levees to raise the water tanks or wells to irrigate their crops, the shadouf (Fig.4) (lever mechanism), the tambour (Fig.5) (attributable to Archimedes and known as the Archimedes screw) and the waterwheel saqia (Fig.6) (probably introduced by Persia). These were the first “irrigation pumps� and are still used in the Middle East.

1.3 Southeast Asian Civilizations. Indo and Ganges Rivers

The Harappan and Mohenjo-Daro Civilizations were developed along the Indus River. They were probably pioneers to build the first planned cities in history. Applying the grid method, they managed to design protected cities with citadels, paved roads and a extraordinary complex drainage system. The walls had a dual role, military defence and protection from floods. Each house had a wastewater drainage system with clay pipes, septic tanks and toilets made with adobe bricks. Sewers had openings at intervals for regularly cleaning. All households were communicated with sewage flowing into the streets to the main canals.

Its area was nearly 250 hectares and its population consisted of about 40,000 inhabitants. It seems incredible that almost 5,000 years ago, first settlements had an underground water supply and sewarage system.

Water is an element in constant motion, unpredictable and hard

16

Figure6. Berber region Saqia

Figure5. Tambour. Based on Archimedes screw

W AT E R A N D H U M A N I T Y. A

(1)

complex system of mutual interaction

In India and Bangladesh huge and deep stepwells (Fig.8) very deep receptacles designed to combat evaporation and allow for the harvesting of natural rain water (Shannon, 2008). These receptacles were strategically placed along long trade routes, elevating them to the category of social and religious monuments.

Many domestic routines like bathing, drinking and washing were carried out with these large water tanks becoming lively meeting places for merchants and residents.

(3)

(2)

Figure7. Eastern Fluvial Civilizations map (3000 BCE). (1) Indo Civilization (2) Ganges Civilization (3) Chinese Civilization

to contain. Furthermore, it is considered vital principle generator of life and is a symbol of cleanliness and purity. It is for this reason that water acquires a privileged position in the different religions born in South Asia: Hinduism, Islam and Buddhism. In India, there are seven sacred rivers. Ganges River is considered the mother of all Hindus. Arabs define water as “the mother of all beings�. In Buddhism water symbolizes purity, clarity and calmness.

Water Culture has played a ver tebrating role in formation of societies in South Asia (Fig.7). In major rivers, numerous rules emerged around conversations between sages who applied laws guaranteeing equity in water distribution. Science, ethics and politics concerned water management Humanity was able to work with nature by meaningful logic and using low-tech resources. In this way they managed an efficient use of water.

Understanding seasonal logics, they were able to store water from the monsoon rains for use in dry seasons and adapt their methods of construction to flooding in the rainy season. By a simple process of cut and fill they built safe mounds, while on adjacent lands ponds or dams were dug.

17

Figure8. Stepwells in Rajasthan, India. Panna Meena Amber. Plan and Section

Similarly, the Ghats appeared in South Asia. A gently sloping stairway which establishes a contact between land and water.

Built along the Ganges river, serves as an impor tant economic, social and religious resource. Again becoming a busy meeting point for trade, selling, washing, drying, rest and pray. (Fig.9)

W AT E R A N D H U M A N I T Y. A

complex system of mutual interaction

We can identify three main strategies for the foundation of the first cities: the choice of a high site, walls and levees to protect the city core and a system of ponds for water harvesting.

These strategies usually apply natural logics, it is for this reason that ancient chinese urbanism is often related to Feng-shui rules.

(Fig.10) In the past, when the Yellow River overflowed, the great plain was enriched by sediments. Ancient people gradually migrated from high points towards floodplains to cultivate fer tile ground.

Increasing crops lead to an excessive population growth in few years. Consequetly, they had to build many dams to establish settlements sustained by the productive landscape, multiplying the number of cities and increasing traffic and trade of goods

Figure9. Bathing Ghat in Banaras, 1890. The Ghats, core activities in Indian cities by centuries

1 . 4 C h i n e s e D y n a s t y . Yellow River The alluvial plain between the Yellow (Hoang Ho) and the Blue (Yangtze Kiang) Rivers, gave rise to what is known as the “Cradle of Chinese Civilization�. Devastating floods and repeated effor ts belong of their history. An incredible effor t to control the heavy and frequent flooding events. The Chinese Civilization created an urbanism based on water through a close association between climatic, topographical and hydraulic conditions. Cities were adapted to the continuous presence of water by building canals and artificial ponds creating open retaining synergies with other urban functions such as the possibility of establishing transport routes for goods and building materials. The construction of an open-air network was useful to improve social community and guarantee water supply. Water control was so impor tant, that the first Water Manager in China, Yu the Great, became emperor at the death of Emperor Shun, 2280 years BC. Various dynasties would be remembered as good or bad based on their success in Water Management.

18

Figure10. Circum-city lake-plan of Shangqiu (based on 150000 Topographic maps of Shangqiu County)

W AT E R A N D H U M A N I T Y. A through the flowing Chinese rivers.

Levees were used for military defense, but also played an important role in flood control. Generally, a ring-shaped dike surrounded the walled city giving it a double protection. Often dams could contain the floods dam but the gradual accumulation of silt dangerously increased the level of the surrounding land, leaving the city at lower levels. This meant a major risk to the population as regards exceptional floods.

Retention ponds and drainage were a common feature in ancient Chinese Cities, therefore, were also called “Water Cities�.

Ponds were distributed inside and outside the walls. There have been moats up to 90 and 120 meters wide creating huge lakes outside the dikes. These large bodies of water were used for the production of food irrigating closest lands. Ponds built in the inner cities were made in order to supply the need to obtain land for construction of the beltway or to use it as foundations for new houses. In some cities inner surface area of water could get to cover a third of the city. Even today, water drainage and storage systems are working well in some ancient chinese cities.

From the perspective of modern science of ecology and urban planning, ponds created in the cities have become important wetlands that help to preserve the regional water balance and act as impor tant habitats for native species and wildlife. Chinese water cities attract thousands of tourists each year, curious to observe its famous gardens.

Comparing synergies between settlement-freshwater supply in the four civilizations studied a number of similarities in the strategies to choose the best place to found their cities can be identified. (Table.1) All of them choose high points, that favored its defense but also protected them from floodings. The case of ancient Babylon, the Euphrates River is introduced into the compact city, dividing it into two parts, the Kullab (Nor th city) and Kumar (South city). The Citadel is raised on the left bank of the river and protected by a double wall-moat system. As regards the case of Amarna (the ancient capital of Akhetaten) the city is much more dispersed. It is situated on the right bank

19

complex system of mutual interaction

of the river looking for solid and higher ground. Moving away from the dangerous flood areas, intended cultibables productive land. Therefore a buffer zone between river and settlement was created through vast areas of fertile crops.

Dholavira was an exceptionally planned city. Its first city plan clearly shows the use of a homogeneous net to generate an ordered form a double wall-moat for protection and a whole by means of complex canalized underground sewage system that gave unique health conditions at the time. Strategically placed between two canals, it ensured the entry or exit of water both nor thwards and southwards the city using the force of gravity.

This is an incredible example of urban planning, showing a high level in urban development in Southeast Asia.

Finally, in the chinese case study, Liaocheng, two perpendicular axes from nor th-south and east-west divide the city, coinciding with the main access gates. Achieved high enough to found the city through the system of cut and fill. Thereby creating ar tificial ponds in the inner city walls, so as to allow water retention and also lend it an incredible and recognizable natural beauty.

Mesopotamian Civilization

Egyptian Civilization

BABYLON

AMARNA

Tigris and Euphrates Rivers

Nile River

Tig ris

Eu ph ra te s

Amarna Ni

Babylon

le (8)

(3) (8)

(10) (6) (4)

(3)

(2) (2)

(1) (2) (5) (5)

(7)

(5)

(7)

(1)

(9)

(5)

(6)

(11) (9)

(5)

(4)

(5)

(10)

(5)

(5) (5)

(1) Euphrates River (2) Moat (3) Outer City Wall (4) Inner City Wall (5) Gate (6) Central City (7) Newtown (8) Summer Palace (9) North city (10) South city

(1) Nile River (2) Central City (3) North City (4) North suburb (5) South suburb (6) North Palace (7) Workmen’s village (8) Northern tombs (9) Southern tombs (10) to the Royal Necropolis (11) Modern Cultivation

Southeast Asian Civilizations

Chinese Dynasty

D H O L AV I R A

LIAOCHENG

In

do

Ri

ve

r

Indo and Ganges Rivers

a Gh

gg

Yellow River

ar Liaocheng

w Ye l l o

Dholavira

River

(3) (3)

(1)

(12)

(13)

(4) (14)

(14)

(5) (6)

(2)

(7)

(4)

(1)

(7) (14)

(8) (5)

(7)

(10) (3)

(9)

(4) (11)

(4)

(7)

(2)

(4)

(4)

(6)

(1) Mansar Canal (2) Manhar Canal (3) Castle (4) Bailey (5) Citadel (6) Middle town (7) Lower Town (8) Ceremonial ground (9) Reservoir (10) North gate (11) Dam (12) Outer City Wall (13) Inner City Wall (14) Drainage net

(1) Built-up Area (2) Inner City Wall (3) Canals (4) Retention Ponds (5) Ring-shaped dike (6) Moat (7) Gate

Table1. Fluvial Civilizations. Synergies Settlement-Fresh Water supply

Conferences by TAIPD. Water Scarcity. March 2014

“ No water, no life. No blue, no green. No water, no us” Sylvia Ear le

2

T H E WAT E R C H A L L E N G E Facing an uncer tain future Today human activities increasingly interfere in the natural water cycle, creating a complete dependency between water and humanity. Man has changed topography, vegetation and terrain to its convenience, it has been adapted to the required activity, not being always aware of the environmental impact generated.

Interactions between land and water have altered physical effects on natural cycles, which has caused an indirect effect on the quality and quantity of water circulation.

Using solar energy, nature provides us with fresh water thanks to a huge system of natural distillation. Unfor tunately, 23

this cycle lacks a fair distribution of water.

Places where surface of water evaporation is higher, are areas with low precipitation rate. Arid and semi-arid areas of the world constitute 40% of landmass, receiving only 2% of global precipitation.

On the contrary, humid areas are regions with abundant precipitation. (Fig.11)

2.1 The importance of the Natural Infrastructure Layer The presence of water is key to maintain a system of interconnected ecosystems.

These ecosystems create a network “Natural Infrastructure” which is the

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

equivalent on nature to human ar tificially constructed infrastructure. Therefore, it plays an impor tant role in strategies towards sustainable development. An efficient use of water increases its quality, integrates new water resources and an eco-management of water.

According to the CBD, the Convention on Biological Diversity, management based on the ecosystem would consist on a global strategy for the integrated management of land, water and living resources including the conservation of indigenous species, sustainability and equity.

Water is inextricably linked to climate change, agriculture, food security, health, equality, gender and education and is therefore a key element for sustainable development. Unless we restore a balance between demand and finite supply, the world will face a global deficit of water. A deficiency in water supply would adversely affect the quality of life of individuals and communities.

Droughts cause a strong social and economic impact, depending on the frequency, duration and the extention of interruptions in water supply, health and public safety problems can emerge.

According to the WWDR (United Nations World Water Development Repor t, 2015) (Fig.12), the major challenges for Europe and Nor th America are related to increasing the efficiency of resources and reducing waste and pollution. In addition to the optimization of consumption patterns and the choice of appropriate technology. For Europe, the priority will be a reconciliation between water uses and their respective basins as well as acting with more policy coherence at national and international level.

Asia faces the challenge to mitigate the lack of water due to unsustainable consumption and over-abstraction of surface and groundwater resources that have contributed to increasing water shor tages and threaten long-term sustainable development.

It is therefore necessary to move towards sustainable progress as regards in access to drinking water and sanitation, meet the growing demand for water, reduce pollution, improve the management of groundwater and increase resilience to water-related disasters. The options to improve water supply include water

24

Figure11. Balance scheme of groundwater in a soil column. Recharge areas are those in which groundwater flow has a vertical downward component and for discharge areas has an ascending one.

Figure12. Water Resources Development - Summary Statistics for all Regions. Note that developed countries are more advanced on most issues, but, as expected, not for rain-water harvesting. Asia is more advanced than other developing regions for Water Resources Assessment.

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

harvesting, wastewater reuse and desalination using solar energy.

A key priority for Latin America and the Caribbean will be to ensure the full realization of the human right to access to water and sanitation. Another priority will be to create an institution with capacity to manage water resources and bring sustainable integrated management and use of water resources for socio-economic development and pover ty reduction development.

GLOBAL WATER DEMAND in 2000-2050

The goal for Africa is to achieve a lasting and vibrant participation in the global economy, while its natural and human resources are developed. Currently only 5% develop the potential of African water resources and the average per capita water storage is only 200 m3 (compared to 6,000 m3 in Nor th America).

Only 5% of Africa’s cultivated land is irrigated and less than 10% of the hydropower potential is used for electricity generation.

Currently 20% of the world population has no access to water of enough quality and 50% suffer lack of sanitation. Africa and West Asia are the areas of greatest deprivation. On the whole, it seems that in enriched countries water problem especially affects the conservation of nature and the potential for economic growth while in impoverished or developing countries, lack of clean water is the direct origin of diseases like diarrhea and cholera that caused the death of 15 million children each year.

2.2 The conflict between the scarcity of water resources and its increasing demand According to the World Water Assessment Programme (WWAP), in 2030 we face a global water deficit of 40%. In 2050 global demand for water will increase by 55%. (Fig. 13) This increase is largely influenced to population growth (expected to reach 9.100 million people), rapid urbanization, policies for food and energy security and macro-economic processes such as trade globalization and changing consumption patterns. It is expected that the demand for water will increase in all sectors of production. Water resources are scarce due to the fact theat

25

Figure13. Global water demand in 2000-2050. This graph only measures “blue water” demand (1) and does not consider rainfed agriculture. Note: BRIICS (Brazil, Russia, India, Indonesia, China, South Africa); OECD (Organisation for Economic Co-operation and Development); ROW (rest of the world).

(1) Fresh surface and groundwater, in other words, water in freshwater lakes, rivers and aquifers.

Blue water availability – Natural run-off (through groundwater and rivers) minus environmental flow requirements.

90% of water in the planet is seawater and therefore contains salt and 2% of it is frozen at the poles. Fur thermore, only 1% of all water is fresh water, located in rivers, lakes and underground aquifers. In addition, water must not represent a risk for human consumption and needs to be treated. So, par ticles and organisms that may damage our health have to be removed.

Finally, a complex net of distribution is necessary for water to be consumed.

In 2050, two-thirds of the world’s population will live in cities.

Most of this growth will occur in developing countries that have

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

limited capacity to deal with this rapid change. (UN DESA, 2014) Rapid urbanization, increasing industrialization and improving living standards lead to the increase the overall water demand in cities. However, these cities might become new challenges and oppor tunities for a sustainable development.

Cities affect the natural water cycle by removing significant amounts of water from nearby surface and groundwater sources. In addition, because of their extension cities waterproof their surface thus preventing groundwater recharge and increasing flood risks. The impact of cities on water resources goes beyond its borders. A large par t of water consumed in the city comes from outside its boundaries, causing pollution by discharged untreated wastewater to downstream flow. There is also a virtual demand: cities impor t large quantities of food, consumer goods and energy, which require large amounts of water at the point of production, transpor tation and sale.

Predictions about water-related resources are bleak. Climate models show greater weather uncer tainty, with rainfall irregularities and more intense and longer droughts. The world is facing

many challenges related to water : feeding a growing population, 7,300 million people, with an average growth of 150 per minute, 180,000 per day and so exponentially.

In recent decades, population growth and water demand has not followed a linear relationship. Water demand has doubled, whereas the world population is growing by 80 million people per year (USCB, 2012). Agriculture will have to produce 60% more food worldwide (the ratio rises in developing countries).

Inequalities generated from water demand, especially in the production of food and energy, increase the risk of conflict and generate a strong impact on the local economy and human welfare.

With current growth rates demand for water for agriculture is vir tually untenable. Today, agriculture is already the largest user of water worldwide, accounting for about 70% of all freshwater withdrawals and over 90% in most of the least developed countries (WWAP, 2014). The sector should increase efficiency in water use, reducing losses and increasing productivity of crops.

Efficient irrigation practices can significantly reduce the demand for water, especially in rural areas. (Fig.14) PRINCIPLE 1. Improving efficiency in the use of resources is crucial to sustainable agriculture.

PRINCIPLE 2. Sustainability requires direct action to conserve, protect and enhance natural resources.

PRINCIPLE 3. Agriculture that fails to protect and improve rural livelihoods and social well-being is unsustainable.

PRINCIPLE 4. Enhanced resilience of people, communities and ecosystems is key to ssutainable agriculture.

PRINCIPLE 5. Sustainable food and agriculture requires responsible and effective governance mechanism.

Figure14. The Five Principles for Sustainable Agriculture. The principles are interconnected and complementary and should often be considered simultaneously. They support the three dimensions of sustainable development. the first two principles directly refer to the environment, while the third refers to social and economic development. the fourth and the fifth underpin all three dimensions of sustainable development. for the application of all five principles, a range of actions can be taken to enhance agricultural productivity and sustainability.

26

T H E W AT E R C H A L L E N G E . Facing Many world regions have reached the limit of water use, which has led to over-exploitation of the surface and groundwater resources, creating a strong environmental impact. 20% of the world’s aquifers are being overexploited, especially in intensively used agricultural areas and around numerous megacities. The amount of groundwater has decreased considerably, leading to serious consequences, such as land subsidence and saltwater intrusion in coastal areas. Climate change will increase the risks associated with the distribution and availability of water resources. Increased variability in precipitation patterns, wich many countries have already begun to experience, causes direct and indirect effects on the entire water cycle. As well as changes in groundwater recharge, runoff and water quality.

Exhaustion of groundwater is a serious threat to food safety.

Most of the world’s population lives in shared basins, which means more competition for their use. More than three quarters of the total population are located in international basins; which site 47% of the population is in shared basins. (Ramírez, 2006). Excessive consumption of water in some areas have had dramatic impacts on the environment. In the United States, Chi-

an uncer tain future

na and India, groundwater is being consumed more rapidly than it is replenished, and constantly declining water tables. (Fig.15) Some rivers, such as the Colorado River in the western United States and the Yellow River in China, often run dry before reaching the sea. In China, the Nor th groundwater aquifers have declined dramatically. The Aral Sea in Central Asia has already lost half of its length. Lake Chad, in Nor th America, was long ago the world’s sixth largest, now has lost nearly 90% of the lake surface.

The strong growth of world’s population, which in fifteen years will reach 8,500 million people, compared with 7,300 million today, and that will increase to nearly 10,000 million in 2050, requires a deep reflection on the need for increased effor ts towards sustainable development worldwide. According to the United Nations study, half of the world population will be concentrated in India, which will surpass China, Congo, Nigeria, Ethiopia, Pakistan, Indonesia, and the United States. While Asia and Africa keep growing. Europe has continued to lose population due to low bir th rates, leading to an increase of aging that does not guarantee population replacement.

Figure15. World map of underground water resources and recharge. Overlaying areas with over-exploitation of groundwater and areas with low rainfall (2012). Note that despite having plenty of water in the subsoil and frequent rains Northeast China and North America have serious problems of overexploitation of its aquifers.

27

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

Humanity faces the challenge to achieve a correct, balanced and intelligent management of environment and available resources. A harmony among all nations, ensuring dignified survival of human beings and their habitat as a fundamental objective. For most regions, the problem is not lack of water, but poor management and distribution of water resources. We can say that we are reaching the limit of freshwater withdrawal of land surface, but consumption is increasing. Current water management practices are often too fragmented, solutions used are not optimal and these factors could lead to a loss of possible synergies.

Observing how easily the sources of surface and ground water are depleted we should go further and deepen in the search for innovative solutions such as reverse osmosis, desalination or regeneration in order to satisfy high demands.

2.3 Climate change and impacts on water supply in Europe Different studies indicate a clear trend towards an increase in European annual mean temperature. Since the late nineteenth century, the temperature has continued to rise, but within recent decades there have been the most rapid increases. The decade of 2002-2011 was the warmest on record worldwide.

The highest temperatures were reached during the month of July in the Mediterranean. Climate change primarily affects natural systems, such as glaciers or ecosystems as well as social and economic systems, such as human health and agriculture.

Heat waves will increase in frequency and duration. Model projections predict that between 2071y 2100, in most of southern Europe may double the number of days that combine a warm day (temperature above 35°C) and a tropical night (minimum temperature above 20°C). The most serious increases are projected in the Mediterranean coast: densely populated areas which could be restricted and low-lying river basins and could see its rivers and soils become saline, destroying crops and altering their river ecosystems.

Lack of water can pose serious consequences for citizens of 28

Europe and most of economic sectors, including agriculture, energy production and industry. Climate change will affect not only water supply but also water demand. Water demand for irrigation will rise, eventually slowing the flow of rivers, reducing its ability to dilute pollutants and placing them under permanent water stress. (Fig. 16) Some countries use more than 80% of total freshwater to abstraction for agriculture. In addition to the high demand for irrigation will increase the competition for water, growing evapotranspiration will put pressure on the use of water for irrigation in drought prone areas. For example, in some Mediterranean regions, decreased water availability makes the current irrigation practices impossible in the future.

Thus, as the temperature increase is widespread throughout Europe, the annual precipitation has varied differently between the nor thern and southern Europe. In nor thern Europe the annual precipitation has increased, especially during the winter, but has declined in the south, especially during the summer months, when demand grows due to seasonality generated by tourism.

Annual precipitation trends since 1950 show an increase of up to 70 mm per decade in nor theastern and nor thwestern Europe and a decrease of up to 70 mm in some par ts of southern Europe. (IPCC, 2012). Instead, increase the number of consecutive dry days in southern and central Europe and decrease in the nor th.

Throughout the decades drought that could affect water resources could occur. Crop productivity could be negatively affected in southern European Union, the western par t of Germany and United Kingdom due to the decrease on river flow, levels of reserves and aquifers. Instead, Scandinavia and nor theastern Europe countries may see increased water resources and therefore their flow. (Fig.17) Due to the increase in temperature and the consequent decrease of frost, overall productivity may increase in nor thern Europe.

European cities and urban areas are increasingly vulnerable to extreme weather events. Increasing occupation of urban land

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

Figure16. Annual water stress for present conditions and projections for two scenarios. Note: Yellow: low water stress (withdrawals-to-availability ratio: 0-0.2); orange: mild water stress (withdrawals-to-availability ratio: 0.2-0.4) : red: severe water stress (withdrawals-to-availability ratio: >0.4). In the Economy First scenario water stress shows a large increase for the 2050s across much of Europe compared to the current situation. The implementation of a sustainable approach to the management of Europe’s water resources is investigated in a ‘Sustainability First’ scenario. This scenario sketches the transition from a globalising, market-oriented Europe to environmental sustainability, where local initiatives are leading. Scenarios are based in General Circulation Models and Regional Climate Models (GCM-RCM) combinations.

and population growth has increased the exposure to climate impacts such as heat waves, floods and droughts. (IPCC, 2007) Strong impacts due to flooding in urban agglomerations such as the Belgian, Dutch and Norwegian coast and the regions near Barcelona, Venice and Ljubljana are foreseen. Southern Europe would be most affected because of their urban form, more compact and higher hot days. In contrast to the majority population of coastal areas not positive impacts are anticipated due to the disminucuón of flood risk, for example in Poland and Por tugal.

(EEA, 2012).

Population health is also par ticularly sensitive to potential impacts from climate change, especially cer tain age groups, who may be affected by increased and continuous heat waves or floods. The physical structures that make up the city as their own settlements, roads, railways, airpor ts, por ts, power plants, are especially sensitive to future floods. This could be a problem for cities in nor thwestern Europe bordering the Atlantic Ocean wich often face both river floods and storm. Rising sea levels

29

would cause a change in the heights of coastal storm surges increasing the risk of flooding.

The Mediterranean region has suffered significant impacts due to reduced precipitation and increased temperature. Water availability has decreased and thus the crop yield is lower. The risk of drought has increased, along with forest fires and heat waves. Variation in rivers’ runoff may cause serious changes in the Mediterranean sea as regards an increase of its temperature and its salinity. Biodiversity suffers factors such as soil pH change, invasive alien species, overexploitation of natural resources and air pollution. Environmental flows, which are impor tant for the maintenance of healthy aquatic ecosystems are threatened by the effects of climate change and socio-economic developments.

The hydropower sector is also being affected by lower water availability and an increment of energy demand, especially for cooling processes during the summer. The economic impact that can generate a drought can be impor tant. That was the case in

T H E W AT E R C H A L L E N G E . Facing

an uncer tain future

Figure17. Projected change in minimum river flow with return period of 20 years. Relative change in minimum river flow for a) 2020s, b) 2050s and c) 2080s compared to 1961-1990 for SRES A1B scenario.

Note: It can be seen an increase in the minimum flow of Scandinavia and a decrease in southern and southeastern Europe. Due to the anticipated decline in summer precipitation accompanied by rising temperatures are expected droughts more severe and more common in river flows east and south Europe (Benelux, France, western Germany and the United Kingdom)

Catalonia, where the 2003-2007 drought caused a reduction of hydropower for more than 40% (Generalitat de Catalunya, 2010). This intense drought led to a 40% decrease in cereal production. In Lithuania low rainfall in 2006 led to a 30% fall in agricultural production, with an estimated 200 million euros loss.

In Slovenia, in 2003 direct losses are estimated at around 100 million euros are attributed to drought . (EEA, 2012) In conclusion the most vulnerable to the impacts of climate change on European regions would be first coastal regions with high population density, where the problem of urban heat may be relevant, in par ticular those with high dependence on tourism in summer. Similarly, mountain areas highly dependent on winter tourism could be affected, not only economically but also with a risk of flooding.

30

Areas where impacts may be more severe (mainly in the south) are also those with lower resilience. Undoubtedly, the right design for future urban growth, good urban management of resources, improving green infrastructure and integrated vulnerability of the various European regions would prevent socio-economic imbalances and an achievement a greater territorial cohesion evaluation.

Source: http://desdevenus.com/agua-alcalina-mito-o-realidad/ (2014)

“ Water should not be judged by its histor y but by its quality” Takashi Asano

3

R E C L A I M E D WAT E R To w a r d s a n i n t e g r a t e d w a t e r c y c l e m a n a g e m e n t 3.1 Reclaimed water background First wastewater reuses occurred about 3,000 years ago in Crete, in ancient Greece, providing sewage water to irrigate crops during dry periods. The aim of this point is to provide a brief description on water reuse evolution along decisive events in our history. (Table 2) The mid-nineteenth century was pivotal for water reuse as wastewater collection systems became more prevalent and served to improve sanitation by conveying household wastes away from urban dwellings into the nearest water courses.

33

Unfor tunately this practice of using “dilution” as a “solution” to pollution, still persists in the 21st century water management paradigm.(Asano, 1998) The considerable river Thames pollution passing through London, not only caused nauseating conditions to its citizens but also was responsible of repeated cholera epidemics caused by discharge untreated wastewater to river flows. To fix this issue a large interceptor along the Thames river was built, carrying wastewater downstream to a “sewage farm.”

The aim of a sewage farm, which proliferated in the early 20th century in Europe

an integrated water cycle management

In 1906 was published in the Monthly Bulletin, California State Board of Health, the first reference in relation to water quality requirements for water reuse. Using water retained in Oxnard septic tank for crops irrigation. “Why not use it for irrigation and saving valuable fertilizer properties in solution, and at the same time completely purify water? The combination of the septic tank and irrigation seems the most rational, inexpensive and effective system for this state.”

In 1915, the United States Public Health Bulletin, noted that if an effluent from a septic tank was poured into a shallow trench, 30 cm below from soil surface, it could advantageously be used to grow roses and shrubs, as maize, which edible parts are produced above soil surface.

By mid-twentieth century first reused water was used for industrial supply. Chlorinated wastewater effluents were used for processing steel in the Bethlehem Steel Company in Baltimore, Maryland. In 1955, the Tokyo Metropolitan Sewage Bureau also star ted recycling waste water for industrial uses.

In 1960s, new strategies on urban planned water reuse were developed in order to response California, Colorado and Florida rapid urbanization. 60s are considered the “Era of Water Reclamation and Reuse”. A transition point between lack planning and the star t of new key policies to implement reclaimed water applications. Like Israelian Ministry of Health issued in 1965 specific regulations to allow secondary water effluents be reused for crop irrigation. Vegetable crops eaten uncooked were excluded for human consumption.

EARLY WATER AND SANITATION SYSTEMS: 3000 BC to 1850

During the twentieth century, the growing need for reliable water coupled with environmental concerns about discharge of wastewater into fragile ecosystems and the increasing costs and energy requirements of wastewater treatment has spurred progress in water reclamation and reuse. (Asano, 1998)

PERIOD

GREAT SANITARY AWAKENING: 1850 to 1950

and United States, was the elimination of waste from population centers to prevent disease proliferation. Consequently, water was used for crop production away from city centers.

ERA of WASTEWATER RECLAMATION, RECYCLING and REUSE: POST 1960

R E C L A I M E D W A T E R . To w a r d s

LOCATION

3000 B.C.

Crete, Greece

97 A.D.

Rome, Italy

EVENTS Minoan civilization: use of wastewater for agricultural irrigation The City of Rome has a water supply commissioner, Sexus Julius Frontinus

1500-1700

Germany, UK

Sewage farms were used for wastewater disposal

1800-1850

France, England, USA

Legal use of sewers for human waste disposal in Paris. (1880), London (1815), and Boston (1833)

1848

England

Cholera epidemic. Sanitary Status of Great Britain Labor Force: Chadwick report “The rain to the river and the sewage to the soil"

1875-1900

France, England

1890

Mexico City, Mexico

Drainage canals were built to take untreated wastewater to irrigate an important agricultural area north of the city

1906

Oxnard, California

The earliest reference related to a public health viewpoint of water quality requirements for the reuse of wastewater on the Oxnard septic tank system

1926

United States

In Grand Canyon National Park treated wastewater is first used in a dual water system for toilet flushing, lawn sprinkling, cooling water and boiler feed water

1955

Japan

Industrial water is supplied from Mikawajima wastewater treatment plant by Tokyo Metropolitan Sewerage Bureau

1948

Israel

First water reuse legislation. First Water Reclamation Plant for agriculture in 1969

1960

California

California legislation encourages wastewater reclamation, recycling and reuse

1968

Namibia

Direct potable reuse begun at Windhoek’s Goreangab Water Reclamation Plant (WRP)

1984

Monterey, California

Monterey Wastewater Reclamation Study for Agriculture

1989

Costa Brava, Spain

The CCB, Consortium of the Costa Brava start of supply reclaimed water for irrigation for golf courses. According with the guidelines established

by WHO same year

2000

Madrid, Spain

The city council built a ring of reclaimed water supply for gardening and flushing with European cohesion funds t

2002

Singapore

Reclaimed water produced by Singapore’s Public Utilities Board. Called NEWater, the result is potable, but is mostly used by industries requiring high purity

2002

Wulpen, Belgium

Sustainable groundwater management using reclaimed water: the Torreele/St-André case

2006

Barcelona, Spain

Start up of El Prat WRP. Water is used for urban and industrial uses, environmental and recharge against saltwater intrusion. In 2009 gardens of Montjuïc mountain started to be irrigated with reclaimed water

Microbial pollution of water demonstrated by Pasteur. Sodium hypochlorite disinfection.

Table 2. Milestone events in the evolution of wastewater treatment, reclamation, recycling, and reuse

34

R E C L A I M E D W A T E R . To w a r d s Today, Windhoek, Namibia’s capital, is a pioneer example on direct water reuse for drinking water. Reclaimed water is re-introduced on water supply network and it is re-distributed. Namibia’s case is nearly unique in the world. Cer tainly from 1968, an extensive research on direct potable reuse of wastewater has done make it happen.

An intense drought period in California during 1970s caused many adverse effects. The State Water Management promoted two impor tant strategies: Publishing a “Practical Guide for irrigation with reclaimed water” and implementing a demo-project.

Monterey’s demo-project served to verify that reclaimed water irrigation rules for raw vegetables consumed ensure health and environmental prescriptions. This guide, published in 1984, represented a landmark contribution for scholars and professionals in irrigated agriculture.

Today, pioneer studies have a common goal: create new strategies to generate reliable new water supply sources to face weather irregularities. The Groundwater Replenishment System in Orange County Water in Southern California has been applied new water sources after more than 30 years of studies and previous demonstrations. Wulpen’s coastal regenerated dunes, in Belgium and NEWater project in Singapore are also examples of pioneers countries using reclaimed water for non-potable uses.

3.2 How to obtain reclaimed water?

This point presents a kind of water that is little known to many, but that may be also key to cer tain world areas that need urgent water alternatives. Social awareness on water as a finite resource is deepening, but this is not enough. Search for alternatives to mitigate water scarcity effects, such as the reclamation and reuse of treated water are indispensable.

To get an idea of the amount of available resources in a geographic area, must calculate its water balance. Balance calcula-

35

an integrated water cycle management

tion is obtained as the result between the difference with annual water supply total inputs (precipitation, rivers, aquifers and transfers) and annual water losses, unrecoverable water, whose destination is the air or the sea.

Today, in a normal water cycle, water has been used, purified and returned to its source, either river or sea. This last step is not a problem in times of plenty of water, but when system experiences more outputs than inputs. Water resources (reservoirs and aquifers) star t to run out involving consequently a water deficit that can induce, during extended periods, a drought. The Spanish’ weather case, where exist areas with low rainfall and long dry periods, force to rationalize and optimize water resources. This condition, along with an increased demand, causes the need to seek new complementary or alternative resources.

(Magrama, 2010) Then, it is impor tant to make clear the meaning of terms such are Reclaimed water, Purified water or Water reuse. The RD 1620/2007, of 7 December, establishes the legal system governing the reuse of treated water in Spain.

Purified water is defined as water that have undergone a treatment process in order to satisfy water supply quality standards.

Reclaimed water is understood as treated wastewater that have undergone additional and complementary treatments, in order to bring enough quality standards to be used in the future.

Reclaimed water involves purification in order to be reused, while purified water not always opt to be reused. Its destiny is to be poured into a water network or into the sea. On the other hand, there are different ways to call reclaimed water : in Southeast Asia (Singapore) is called NEWater, in Spain and Latin America is known as Regenerated Water and, in England, it is accepted as Recycled Sewage.

At this point it is also appropriate to define the concept of water reuse. It is understood as varied water applications for new exclusive uses. Before be returned to environment, used water has undergone purification processes established to achieve

R E C L A I M E D W A T E R . To w a r d s

an integrated water cycle management

minimum quality standards depending on uses to which will be destined. (RD 1620/2007) Wastewater reuse is a historical practice, in many world regions is required by seasonal shor tage and/or structural lack of water as well as the need to better manage of available water resources. Reclaimed water use, an unconventional resource, frees better quality water for human consumption. Therefore, it is necessary to enhance water sustainable development and protection of this scarce and necessary resource maintaining the balance between human health protection and sustainable strategies.Thus, must understand water reclamation and reuse as a real increase on exploitable water resources in a cer tain area, given that, otherwise, these resources are lost irretrievably, by pouring it to the sea or to the riverbed.

It is also necessary to distinguish between direct and indirect reuse. As the civil engineer, Rafael Mujeriego says, indirect reuse has been going on from long ago. Discharges upstream have been dissolved in rivers and swamps and have been recaptured again to be consumed. “Most of us live downstream”. Therefore, this was an accidental reuse, unplanned, involuntary. While in direct reuse, water is discharged in a greater or lesser degree, for reuse through a specific duct without being dissolved in other sources.

Planned water reuse in Catalonia, as in other areas of Spain, has received considerable attention and development since 1980s.

Barcelona Metropolitan Area is pioneer in water reclamation research. The Baix Llobregat Waste Water Treatment Plant (WWRP) (Fig.18) is one of four metropolitan wastewater plants that include advanced water treatments, then, they have also incorporated a Water Regeneration Plant (WRP). El Prat plant is one of the most important regeneration infrastructures in the world and can increase regional water resources by 50 million cubic liters of water per year.

As the engineer and reclaimed water guru affirms, Takashi Asano, in a moment of necessity, we are going to blr able to bring water from “Toilet to Tap”.

36

(1)

(2) (3)

Figure18. Overview of Baix Llobregat Water Reclamation Plant. (1) Purification Process -Primary and secondary Treatment- (2) Advanced Treatment -coagulation-flocculation- (3) Membrane Processes -Reverse Osmosis-

·PURIFICATION PROCESS Pre-treatment Water from sewage, once enters into a wastewater treatment plant (WWTP), passes through a series of procedures in order to return it to nature in optimal conditions. Pre-treatment comprises a series of physical treatments that seek to separate larger solids contained in wastewater. In order to complete initial purification process, water flows through grates placed in series shrinking its distance from bars to sieves.

Grit chambers are used to remove sand contained in water. It flows through canals with diverse speeds, in some cases with aeration, and mechanical elements remove sedimented sand from the bottom.

R E C L A I M E D W A T E R . To w a r d s

Primary Treatment Main objective on primary treatment is to reduce suspended solids presence (SS). This process consists in to store temporarily water in settling tanks. Pre-treated water remains stored for a while, usually comprises between 1,5 and 2,5 hours. Treatment success is measured in solids presence reduction (is convenient to be between 50% and 70%).

an integrated water cycle management

uble substance. The most widely used coagulants are metallic salts such as aluminum polychloride, aluminum sulfate or ferric chloride. Then, a flocculant is added. It destabilizes molecules that come in contact with it, enabling flocs growth and causing more precipitation. The floc-water separation is accomplished by a decantation process.

Secondary Treatment Secondary treatment consists basically in to accelerate ar tificially biological processes that would occur in nature. Most commonly used technology is a biological treatment by Activated Sludges.

It involves to mix in a reagent (in chemistry, a substance that can reveal the presence of a different substance that, through interaction gives rise to a new product) suspended biomass on water by stirring and aeration and let microorganisms purify water. Secondary treatment final stage clarify water via traditional method of decantation. Membrane BioReactor systems (MBR) are used to replace decantation step by a filtration process.

Microfiltration membranes or ultrafiltration are the most used.

These filters remove contaminants and other nutrients from water that microorganisms were not able to eliminate before.

After this treatment it is considered that water is enough purified to be returned to its origin ensuring optimal environmental conditions.

¡ADVANCED TREATMENTS Coagulation-flocculation This treatment is based in chemicals addition combined with decanter physical action. It is a process in which par ticles are grouped in small masses called flocs, so that, its specific weight overcomes water’s weight and thus, can precipitate. First, a coagulant is introduced into purified water. In this process dissolved matter that could not be decanted before, becomes an insol-

37

Table 3. Operating diagram adaptation from El Prat WWTP. Note: WWTP (Wastewater Treatment Plant) WRP (Water Reclamation Plant). Since 2002, el Prat WWTP provides service to 35% of Barcelona city, in addition, South Barcelona Metropolitan Area municipalities. Which is equivalent to a throughput of two million inhabitants. In 2006 started up the WRP with 3.25 cubic meters per second of flow rate..

R E C L A I M E D W A T E R . To w a r d s

an integrated water cycle management

Membrane Processes Membrane processes are considered cutting-edge technology being widely used in advanced water treatments. Based on non destructive technologies, micropollutants are separated by a selective water flow across semipermeable membranes.Therefore, membrane processes are the best known for water advanced treatments, such as Microfiltration, Ultrafiltration, Nanofiltration and Reverse osmosis. (Fig. 19) Par ticles and colloids are separated applying high pressure. Thus, differences between these techniques are pore’s diameter. Microfiltration removes suspended solids over 0.1 microns. Ultrafiltration removes essentially all colloidal par ticles, dissolved contaminants any larger (0.01 microns) and most of pathogenic microorganisms. Water treated by this system has virtually no turbidity. Nanofiltration removes contaminants greater than 0.001 microns. It is used to remove all dissolved solids. Ions of calcium and magnesium, which contribute to water hardness are also deleted. For this reason this process is also called softening process.

In reverse osmosis, an applied pressure is used to overcome osmotic pressure, a colligative property, that is driven by chemical potential, a thermodynamic parameter. Reverse osmosis can remove many types of molecules and ions from solutions, including bacteria, and is also used in both industrial processes and the production of potable water. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side.

In the normal osmosis process, the solvent naturally moves from an area of low solute concentration (high water potential), through a membrane, to an area of high solute concentration (low water potential). The movement of a pure solvent is driven to reduce the free energy of the system by equalizing solute concentrations on each side of a membrane, generating osmotic pressure. Applying an external pressure to reverse the natural flow of pure solvent, thus, is reverse osmosis. (Fig. 20)

OSMOSIS

EQUILIBRIUM

REVERSE OSMOSIS APPLIED PREASURE

OSMOTIC PREASURE MEMBRANE

Figure19. Scheme of most used membrane processes for advanced water treatment. Conventional filtration could only do particle filtration, membrane filtration such as ultrafiltration, nanofiltration, and reverse osmosis is nowly needed to deliver high standard of water in many cases.

38

FEED

PURE

FEED

PURE

FEED

PURE

WATER

WATER

WATER

WATER

WATER

WATER

Figure20. Reverse osmosis diagram. First, water flows from low concentration of salts to a higher concentration, this is natural osmosis. Then, osmotic preassure is the preassure required to stop water flow and reach equilibrium. Finalilly, by applying pressure greater than the osmotic pressure, flow of water is reversed. Water begins flowing from higher concentration to lower.

R E C L A I M E D W A T E R . To w a r d s

an integrated water cycle management

Reversed Electrodialysis

3.3 Current legal context

Electrodialysis is a electrochemical separation process in which ions are transferred through the membrane from low concentrated solution to a high concentration solution, as a result of electrical current application. Membranes are arranged alternately as anode and cathode. Electrodes are responsible to apply the potential difference. Cationic membranes allow the passage of positive ions and anionic membranes let pass negative ions. The aim is to obtain a concentrate solution and a dilute effluent. For an efficient membrane maintenance it is usual to reverse electrodes polarity from time to time. Thus, is reversed electrodialysis.

There is no European legislation on the reuse of reclaimed water currently. The single European reference is Article 12 of Directive 91/271 on waste water treatment. It indicates that treated wastewater will be reused where will be appropriate; however, it does not specify what is meant by appropriate.

Disinfection Finally, in order to ensure safety and quality of reclaimed water, perform different disinfection processes depending on purication objectives. Reclaimed water should reach its destination with quality and disinfection standards required. Disinfection involves selective destruction of disease organisms. Derivatives of chlorine NaClO (sodium hypochlorite) are the most widely and best known.

Ozonation case, ozone microbubbles produced intensively by a generator react with organic material, oxidizing it and creating a reaction. Thus, it acts mainly against viruses and bacteria. At the same time, it reduces odors, does not generate additional dissolved solids and increases effluent oxygenation.

Other disinfection treatment made by physical agents is ultraviolet radiation (UV). Unlike the previous ones, which are chemical methods, this is physical, which implies the absence of residues.

UV is based on the action of an electromagnetic spectrum on nucleic acids and proteins. Thus, present microorganisms and pathogens are inactivated. It is particularly active against bacteria and viruses.

39

Directive 91/271 is a standard provision of Community law binding on the Member States to meet certain targets within a given period, leaving to national competent authorities the choice of how and appropriate means to that end.

There are several Member States with legislation. One of them, Spain, with RD 1620/2007, others such as France, are based on recommendations that follow essentially those established by the World Health Organization (WHO). Varied forms and standards that are considered within the various states that compose the European Union. In Italy, for example, new reuse standards were established by preparing a ministerial decree.

It is rather restrictive and in some cases required quality is the same as for drinking water. In contrast with other countries like United States where, reclamation and reuse of waste water are perfectly implemented. California, is a pioneer State in this area.

Other countries such as Israel, where water is a scarce commodity, the appearance of his first legislation regarding water reuse took place in 1948.

Currently, many countries star ts to consider water reuse a tool for managing its resources and have facilities and technology to carry it out. Fortunately, there are many governments that are interested to invest in the technologies needed to implement reclaimed water infrastructural projects.

4

I N T E G R AT E D P L A N N I N G 22@ Distr ict, the NewBlue Infr astr ucture Layer 4.1 A new source of supply to close urban’s water cycle.

Cities grow, population grows and water supply sources are increasingly distant.

Environmental and health requirements new reservoirs construction and wastewater discharge are increasingly stringent and climatic trends point to frequently droughts indeed. These factors have made reclaimed water will become a sustainable and secure alternative to water city cycle.

As we star ted to see in the previous chapter, a planned water reuse program essential standards aims are to minimize 41

potential, direct or indirect, risks to environment, people who use it, surrounding population or consumers of any product cultivated with reclaimed water.

Therefore to constitute a program core of planned water reuse, three basic elements are required: - Transportation (canalization) of reclaimed water from Reclamation Plant to the point of use.

- Temporarily store and water regulation, to match the pressure supply between the plant and the users.

- Implement the application of sanitary and environmental standards.

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

Depending on whether exists possible reclaimed water contact or ingestion, its reuse is classified into reuse for potable use and reuse for non-potable use. In the first case are included the applications in which people can ingest eventually reclaimed water and in the second case are included the rest of cases. It is impor tant to note that, so far, regeneration projects for non-potable uses have been most widely used and socially accepted in many par ts of the world.

Some of main standards set by health authorities are: signaling through visible signs indicating water used type; adopt purple color for pipes and control devices; installation of backflow devices; periodic inspections on network connections; specific hours for irrigation and news sprinkler types; prohibition of outside taps and use of different pipes and hydrants from those used for drinking water connections. (Fig. 21) Reclaimed water has many and varied uses. The highlights are: parks and gardens irrigation, urban uses, cooling towers for industrial uses, recharge overexploited aquifers for environmental uses or whether agricultural irrigation for hor ticultural crops (direct consumption) or fur ther processing crops such as cereals or vines. (Table 4) Water reuse for irrigation and gardening has been primary application in developed strategies for resources management. The fact that water consumption in agriculture, along with growing gardening in developed countries, is higher than overall consumption in urban and industrial uses, has favored the interest in reclaimed water as a way to have additional (non-conventional resources) of greater reliability. Very many countries spend about 80% of their water resources on crop irrigation; also if we consider semi-arid areas with frequent episodes of droughts, it is logical that both Spain and the United States has emerged an impor tant interest researching unconventional resources.

As the previous chapter indicates, the Groundwater Replenishment System in Orange County Water District and the Orange County Sanitation District is an emblematic example worldwide, giving an environmental use to reclaimed water. With an annual

42

allowed uses to reclaimed water Figure 21. Network elements of reclaimed water. Since 2001 Víbora WWTP in Malaga, supplies water to irrigate golf courses as Sta. Maria or Cabo Pino. Manhole cover from Madrid reclaimed water network. In 2001 it begins the construction of a large beltway of nearly 200 km to irrigate parks and gardens.

URBAN

- Residential: Private gardening and toilet discharges - Public Services: Irrigation of urban green areas, street cleaning,fire extinguishing systems and industrial washing of vehicles

- Irrigating crops with water application system that

AGRICULTURE

INDUSTRIAL

RECREATIVE

allows direct contact of reclaimed water with edible parts for human consumption - Irrigation pastures for consumption of milk producing animals or meat - Crop irrigation of ornamental flowers, nurseries and greenhouses - Aquaculture

- Process water for industrial uses and cleaning - Cooling towers and evaporative condensers - Irrigation golf courses - Ponds, water bodies and ornamental circulating flows, preventing public access to water

- Aquifer recharge by direct injection or through the ENVIRONMENTAL

terrain

- Irrigation of forests, green areas and forestry - Maintenance of wetlands and minimum flows

Table 4. Reclaimed water uses allowed under the Spanish RD 1620/2007

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e production of 90hm3 of water, which 47hm3/year are dedicated to aquifer recharge, while 43hm3/year remaining are used to replenish saltwater intrusion barrier. It is also significant reclaimed water low production cost, which is about $0.65/m3 reduced to $0.40/m3 after federal, statal and the Metropolitan Water District of Southern California grants application. (Table 5).

Another example we have already mentioned, is the initiative put forward by the Metropolitan Area of Barcelona that allows members of the user community of the Llobregat delta aquifer to use high quality reclaimed water for industrial uses, in exchange for interrupting extractions in the overexploited aquifer.

Users have better quality water (less saline) that obtained from the aquifer itself allowing its gradual recovery by natural means, mitigating saline intrusion and constituting a strategic reserve of good quality water.

NewBlue Infrastructure Layer

RECLAIMED WATER DISTRIBUTION 0,0575€/m3 (2) ADVANCED TREATMENT 0,3024€/m3 (2) WASTE WATER COLLECTION 0,1095€/m3 (1) WASTE WATER TREATMENT

BASIC REGENERATION Indirect reuse (Spain)

ADVANCED REGENERATION Direct reuse (California)

INVESTMENT

≈ 0,25€/m3 year

≈ 3,40 $/m3 year

COST

≈ 0,05-0,10€/m3

≈ 0,40 $/m3

POWER REQUIREMENT

< 1Kwh/m3

1,5 Kwh/m3

0,3118€/m3 (1)

Figure 22. Diagram costs of an integrated cycle of water consumption in Madrid. According with rates set by the Canal de Isabel II Management. Note: water treatment additional costs (advanced treatment) and distribution does not exceed 0,36 €/m3. (1) for all applications up to 25m3. (2) Less than 25% of the contracted volume.

Table 5. Required investments, cost and power requirements to recycle water.

Note: Indirect Reuse: Clarification and disinfection processes. Direct Reuse: Membrane processes.

Therefore, water planned reuse benefits are manifold. Reclaimed water provides a supply capable of providing additional water resources, allowing higher quality resources under less pressure, They can be allocated to more demanding applications such as drinking supply. The need to seek additional water contributions far away, thus avoiding potential environmental impacts and reducing energy consumption. It is also very impor tant to increase assurance of supply. Reclaimed water flows are more stable than most natural sources, especially in semi-arid areas like the Mediterranean. (Fig. 22) 43

Then, a planned reuse provides a guarantee much higher than conventional sources, ensuring flow rates availability, especially during summer seasons and promoting more efficient management of water resources. Fur thermore, the proximity of reclamation plants to urban centers offers the possibility local and reliable supply, increasing water self-sufficiency degree and reducing water transfers dependency from external basins.

Next diagram (Fig. 23) shows an example of an integrated water cycle management. In it, is appreciated the amount of non-potable uses that a city requires and how can be supplied through a planned reclaimed water network.

SOURCE Water catchment from natural resources (river basins, reservoirs and aquifers)

WATER TREATMENT For human use, raw water must be treated to remove contaminants and pathogens

DRINKING WATER PLANT

Upstream

RE-USE Reclaimed water can be reused for urban, recreational, agricultural, industrial and environmental uses

Downstream

WATER DISTRIBUTION Water is distributed to customers through a pressurized system of pipes, pumps, valves, and storage reservoirs

USE Water customers use the supplied water for industrial, commercial or domestic purposes

WASTE WATER COLLECTION WATER RECLAMATION PLANT

UV Disinfection

Reverse Osmosis

Microfiltration

WASTE WATER TREATMENT Water passes through Purification Process and Advanced Treatments to be used again safely

WASTEWATER TREATMENT PLANT

Sewers collect used water and convey it, usually by gravity, to a wastewater treatment facility

Before, water was returned downstream

Figure23. Example of an Integrated Water Cycle Management

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

4.2 Hydrological context and requirements B C N M E T R O P O L I TA N AREA

C ATA L O N I A

Average annual rainfall 700mm Last drought periods 98-02/05/07-08 Average consumption 130 l.x person/day Total Demand 3.156 hm3/year WATER USE

(Ebro+Internal Basins)

Irrigation Domestic Industrial Livestock

70% 19% 9% 2%

RECLAIMED WATER Environmental (78%) Recreative (12%) Agriculture (9%) Urban (1%)

WATER SUPPLY NETWORK Surface water 185,8 hm3/year Groundwater 26,6 hm3/year Desalinated water 1,9 hm3/year Total Demand 214,3 hm3/year

WATER USE

(Internal Basins)

Domestic Irrigation Industrial Livestock

43% 33% 21% 2%

51 hm3/year 40 hm3/year 5,8 hm3/year 4,7 hm3/year 0,5 hm3/year

Population: 7.570.908 inhabitants. Data obtained from Catalan Water Agency (ACA, 2013)

WATER CONSUMPTION Domestic use (68%) 146,6 hm3/year Non-domestic use (26%) 55,7 hm3/year Municipality uses (6%) 12,8 hm3/year SANITATION Besos WWTP Total WWTP RECLAIMED WATER Total WRTP (1,4%)

123,7 hm3/year 266,2 hm3/year 3,8 hm3/year

(El Prat WRTP capacity of 50 hm3/year) Population: 3.239.337 inhabitants. Data obtained from environmental statistics of the Metropolitan Area of Barcelona management (2014)

46

22@ DISTRICT

Average annual rainfall 598mm Average consumption 113 l.x person/day WATER CONSUMPTION Domestic use (66,4%) 9,6 hm3/year Comercial/Industrial (29,5%) 4,2 hm3/year Municipality (4,1%) 0,6 hm3/year TOTAL 14,5 hm3/year PHREATIC WATER (GROUNDWATER) Parks irrigation (38%) 0,40 hm3/year Street cleaning (29%) 0,30 hm3/year Fountains (22%) 0,22 hm3/year Sewer cleaning (11%) 0,11 hm3/year TOTAL 1,03 hm3/year* *Aquifer overexploitation in the 60â&#x20AC;&#x2122;s (60 hm3/year) caused saline intrusion (30 hm3/year). According with the Technical use Plan of alternative sources (2009) could extract 5-8 hm3/year.

Population: 233.856 inhabitants. Data obtained from Barcelona City Council (Water consumption in Barcelona. The exploitation and use of water resources, 2008).

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e

NewBlue Infrastructure Layer

CURRENT AND PROPOSED BARCELONA’S RECLAIMED WATER NETWORK

RECLAIMED WATER STANDARDS: BASICAL (QBAS)

CROP IRRIGATION (QRE)

REVERSE OSMOSIS (QRO) PROPOSED REVERSE OSMOSIS (QRO) REVERSIBLE ELECTRODIALYSIS (QRE) (WRP: Water Reclamation Plant)

RECLAIMED WATER USES: WETLAND CONSERVATION (QBAS) INDUSTRIAL USES (QBAS) SALINE INTRUSION BARRIER (QRO) PARKS IRRIGATION (QBAS)

SANT FELIU WRP

gon

gat bre

al A ven

ue

er

Riv

Llobregat Agropark

Dia

Llo

SANT FELIU WRP

Besós River

MONTCADA WRP

Sant Adrià industry Montjuic mountain Zona Franca industry

BESÓS WRP PROPOSED NETWORK

EL PRAT WRP

Figure 24. Current and proposed Barcelona’s reclaimed water network. Reclaimed water plants provide water irrigation to Llobregat Agropark, maintain rivers and wetlands returning water to Llobregat delta, creates a saline intrusion barrier through injection pumps, supplies industrial processes and cleans streets and sewers. In order to supply the opposite city limit, adding advanced treatments to the current Besos waste water treatment plant , could provide reclaimed water to irrigate important city parks and gardens, make a saline intrusion barrier to protect Besos aquifer, provide water for recreational uses along sea front and provide enough quality water for industrial uses in Sant Adria de Besos industrial area.

47

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

The study case is located in a Mediterranean context, dry summers with temperatures above 30 degrees and humid and rainy winters. Although, as we have seen in Chapter 2, summers are getting longer and warmer. It rains less and when it does it is torrentially, leaving in its path numerous incidents. In addition, droughts, also common in the Mediterranean area, will become more frequent.

Cities must prepare to deal with lack of water periods, especially in summer season when water consumption soars. Freeing pressure on drinking water supply network through research of new water resources such as reclaimed water for non-potable uses. Barcelona requires nearly 4 million m3 of water for non-potable uses. Almost 50% of water used for irrigation and maintenance of urban parks is drinking water. The aim of this study is to reduce this ratio to 0 and replace it with reclaimed water.

22@ District in few years has become the Barcelona’s Innovation District. Transforming two hundred hectares of Poblenou’s industrial land in a project of urban renewal introducing a new city model providing a response to challenges for Barcelona’s city future.

Indeed, old industries relocation has caused to rise groundwater level flooding subway stations and underground parkings. (Fig. 26) During the 60’s Poblenou’s industries extracted large amounts of groundwater causing groundwater level decrease.

WAT E R C O N S U M P T I O N F O R U R B A N U S E S hm3/year PARKS & GARDENS BUILDINGS FOUNTAINS STREET CLEANING MUNICIPAL MARKETS ZOO SEWER CLEANING OTHERS TOTAL

1,50 (39%) 0,86 (22,2%) 0,46 (12%) 0,33 (8,7%) 0,29 (7,6%) 0,23 (6%) 0,14 (3,7%) 0,03 (0,7%) 3,84

PA R K S & G A R D E N S I R R I G AT I O N S O U R C E S

hm3/year DRINKING WATER RAIN WATER GROUND WATER TOTAL

0,56 (49%) 0,53 (47%) 0,05 (4%) 1,14*

* Parks & Gardens consumption: 75,9% (1,14 hm3/year) irrigation, 7,8% hydrants 16,2% fountains.

I N D U S T R I A L WAT E R U S E S D I S T R I B U T I O N

WAT E R D E M A N D F R E C U E N C Y 140.000

m3

120.000

hm3/year CHEMISTRY TEXTILE ALIMENTARY PAPER REFINED METAL OTHERS TOTAL

100.000 80.000 60.000 40.000 20.000 0

57,7 (37%) 24,7 (16%) 24,7 (16%) 15,2 (10%) 9,2 (6%) 8,2 (5%) 17 (10%) 156,7*

* Industrial total water demand from Catalan Internal Basins according to Catalan Water Agency, 2014

G

F

M

A

M

J

J

A

S

O

N

Figure 25. Barcelona City water consumption, distribution and demand frequency on urban and industrial uses. Adapted from Barcelona’s water consumption study from Environmental Department of Barcelona City Council

D

48

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e

NewBlue Infrastructure Layer

4.3 The NewBlue Infrastructure Layer NEW BLUE LAYER ELEMENTS:

EXISTING

GROUNDWATER PUMP

ARTIFICIAL LAKE

GROUNDWATER TANK (500m 3)

GREEN AREA

GROUNDWATER NETWORK (278 l/sec)

INNOVATION AREA 22@ MEDIA

PROPOSED

BESÓS WATER RECLAMATION PLANT

R&D

RECLAIMED WATER NETWORK

MEDICAL

RECLAIMED WATER TANK (300m 3)

DESIGN

CITY PARKS IRRIGATED with RW Español FC Sports City

Gran Via Avenue

Flowrate: 278l/sec

aA ve

nu

e

Glories’ Park

an idi er M

Besós Park

Poblenou’s Central Park

Dia

Besos

gon

al A ven

River

ue

1st

Ciutadella Park

3rd Phase

Pha

Diagonal Mar Park

se

2nd Phase

Besós WRP

Figure 26. The NewBlue infrastructure layer diagram. Two new water resources are represented in this diagram, excessive phreatic water network and a new reclaimed water network along South Diagonal Av.

22@ District Infrastructure Plan foresaw a phreatic water network to irrigate parks and clean streets and sewers. Today, the ring has already been completed. Underground water is pumped from two wells and stored in two tanks of 500m3. One pump is located in Besos Mar metro station and the other one in Ciutadella Park. Proposal is based on to convert current Besos Waste Water Treatment

49

Plant in a Water Reclamation Plant to provide reclaimed water to three City Parks in South Diagonal area. Each park should contain a regulation tank. Second and third project phases, are oriented to grow towards Besos river, in order to provide water for its maintenance, Besós Park irrigation, provide water to Español FC training pitches and get industrial uses to Sant Adrià industrial area.

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

The “NewBlue Infrastructural Layer” study indicates that 300 million liters of reclaimed water per year would be enough to maintain three major urban parks linked to South Diagonal Avenue (Glories Park, Poblenou’s Central Park and Diagonal Mar Park). For irrigation water calculation has been considered 1m3 of water to irrigate 3m2 of green area per year. Ornamental water is renewed each three months and 16% of total consumption goes to hydrants for streets and sewers cleaning. (Fig. 27) Therefore considering the three basic requirements to build a reclaimed water network (transportation, temporary storage and compliance with health and environmental standards), would be necessary to build a new reclaimed water network about 3Km long through Diagonal Avenue subsoil (Fig. 28). Each of three city parks must integrate in their design a regulation tank buried or semi-buried with an approximate dimensions of 8x8x4m, about 300m3. Finally, requiered standards for irrigation and maintenance of ornamental lakes will be ensured through regular controls both the Besós Water Reclamation Plant and ponds.

Diagonal Mar Park was designed by the catalan architect Enric Miralles. It is the only one entirely completed. A large artificial lake is protagonist on Miralle’s design. To its maintenance and renovation would be necessary around 48,000m3 of reclaimed water per year, while for green areas irrigation would be needed 31.500m3 more.

Glories new Park is under construction at this moment, its complex underground infrastructure impedes an easy design to introduce water on surface. However presence of water in this park its absolutely necessary to become the Central City Park has never been.

According to Barcelona’s Water Parks comparison study (Table 6), has been considered for this study 15% of its surface will be water.

Finally, the case of Poble Nou’s Central Park, a Jean Nouvel unsuccessful project made in 2008. He’s idea of “fortified park” to isolate the user from city noises is absolutely contrary to Barcelona’s city park model. To guarantee accessibility should be the street continuity itself. It is for this reason that this research proposes a new “Poblenou’s Central Water Park”, where the protagonist element will be unquestionably, reclaimed water.

50

GLORIES’ PARK (20ha) Park irrigation: 67.000m 3 Ornamental: 60.000m 3 Hydrants: 27.500m 3 Regulation tank: 300m 3

POBLE NOU’S CENTRAL PARK (5,5ha) Park irrigation: 18.500m 3 Ornamental: 16.500m 3 Hydrants: 7.500m 3 Regulation tank: 250m 3

DIAGONAL MAR PARK (14,3ha) Park irrigation: 48.000m 3 Ornamental: 31.500m 3 Hydrants: 17.000m 3 Regulation tank: 300m 3 * Water consumption per year

BESÓS WATER RECLAMATION PLANT Estimated annual production: 293.500m 3/year

Figure 27. Proposed reclaimed water network in South Diagonal Avenue. Distance between Besós Water Reclamarion Plant and the farthest point, in Glories Park, is just over 3Km. Note: It is considered1m3 of reclaimed water can irrigate up to 3 m2 of green area. Ornamental water is renewed every three months and it has been considered 16% of consumption goes to hydrants to clean streets and sewers

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e

Reclaimed water network Traffic and street lighting Telecommunications Medium and low voltage

NewBlue Infrastructure Layer

Gas Central heating network

Reclaimed water network

Pneumatic waste collection

Figure 28. South Diagonal Avenue infrastructural section. In 2002, 22@ District Infrastructure Plan wants to give to new Barcelona innovation district services planned under sustainability criteria and efficiency.

Therefore, speciallist opt for central heating networks, variety on telecommunications, pneumatic waste collection and promote a smart use of water facilities. New management model is based on construction of continuous ducts that allow sorting facilities and allow reparations and maintenance services. Furthermore underground criss-cross galleries connect street extrems allowing its connection. So far, wastewater was treated in Besรณs WWTP, incorporating advanced water treatment systems such as reverse osmosis, urban water cycle will be able to be close, using reclaimed water for urban parks irrigation, street cleaning, ornamental water flows and fire extinguishing.

51

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

4.4 Poblenou’s Central Water Park At last, this research aims to design a new Poblenou Central Park, converting it into a prototype of urban design based on water urbanism concept. The proposal introduce reclaimed water as protagonist element, replacing current concrete walls that impede accessibility by water strips. Water presence will eliminate barriers as well as will improve visual and environmental perception allowing synergies between citizens and water.

Based on a comparative study of Barcelona main water parks (Table 6), it has been established some parameters, in order to obtain referential data to calculate annual water requirements for parks maintenance. According to this data is considered that the average surface of water bodies compared with studied parks total surface is around 15%. Consequently, new park’s design could incorporate over 4.000m2 of water. Additionally, has to be built a buffer reservoir (regulation tank) of 250m3 of capacity, connected to the new regenerated water supply network. This tank regulates water pressure and will be the starting point for parks’ water circuit.

It has been estimated an annual reclaimed water consumption of just over 40.000m3 (18.500m3 for irrigation, 16.500m3 for water bodies and 7.500m3 for hydrants).

Fortunately , water culture in city spaces designs is becoming more common. Some referential waterscapes projects such Enric Miralles in Diagonal Mar Park or Renzo Piano’s design in Berlin, has contributed to make possible interactions between water and citizens.

Potsdammer Platz has become one of the most visited places in Berlin. (Fig. 30) In this case, the idea behind is that rainwater should be used where it falls. A combination of green and non-green roofs harvest the annual rainfall. Rainwater then flows through the site’s buildings and is used for toilet flushing, irrigation, and fire systems.

Excess of water flows into the pools and canals of the outdoor waterscape creating an oasis for urban life. Vegetated biotopes are integrated into the overland landscape and serve to filter and circulate water that runs along streets and walkways without the use of chemicals.

Banyoles’ old town urbanization project (Fig. 31) makes “appear” in-

Table 6. Barcelona’s Water Parks comparison study. Note that Pegaso Park has the highest percentage of water presence, almost 30% of its surface is covered with water, however, Can Zam Park is the one with lowest percentage of water surface but is the only using biofilter methods for water maintenance. (*) Proposed Barcelona’s City Parks with an important presence of water. Data has been obtained by taking the average percentage between square meters of water and total park surface. Besides, it has been considered 50cm as depth pond average.

52

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e

NewBlue Infrastructure Layer

Figure 30. Potsdamer Platz view. Renzo Pianoâ&#x20AC;&#x2122;s designed a veil of shallow flow-steps create a rhythmic surface of shimmering waves, providing multiple opportunities for people to cross and interact with the water.

Figure 29. Diagonal Mar Park view. Second largest park in Barcelona. Enric Miralles imagined a wetland to its project since the beginning. A large water lake shares the limelight with grass-covered hills and lush vegetation.

Figure 31. Banyoles old town public space project. MIAS Architects designed this urban intervention made whit travertine stone, always been present in medieval cityâ&#x20AC;&#x2122;s subsoil. Irrigation system is uncovered intermittently across pedrestrian ways. Eventually, it is opened in a bigger sections allowing people interact with water.

53

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

termittently ancient irrigation canals along narrow medieval streets accompanying pedestrians on its way, while in wide spaces sections become bigger creating a call effect for curious and children. Originally, these waterways came from Banyole’s Pond, crossed the city and supplied water to the backyards and the houses. The project restores circulation of people and water through the old town of Banyoles, giving them back the itineraries they occupied originally.

From now on, the pedestrians will always be accompanied by the presence of water.

To G lor tank ie’s

In the same manner as Banyoles or Berlin examples, the Poblenou’s new park design intended that citizens feel accompanied by the presence of water during their presence. In this case, water used for its maintenance will be recycled water wich comes from the proposed Besós Reclamation Plant. After being used, water is returned to the sewer network to continue its recycling process and thus be used again. Following this water-scheme an urban project is able to integrate its own water cycle. (Fig. 32) Poblenou’s Central Water Park is based on two major urban axes, one in Diagonal Avenue because its urbanity, and another in Pere IV street, for its history. (Fig.33). Pere IV axis is a historic space with unique morphology wich articulates Poblenou’s district mobility with an independent path respect Eixample’s geometry. Diagonal Avenue is 50 meters wide, it is also an important exception in Eixample extension. Most emblematic buildings of the new innovation district are placed on it, like Agbar Tower, Barcelona Sky Hotel or Telefonica building. Diagonal Av. also allows high connectivity and mobility rates thanks to the tram line linking its extremes from Forum to Glories’s square.

Park’s location implies the use of geometry to assure permeability and inclusivity on its landscape design. Eixample rigidity seems to be broken in this point, where the confluence of both mesh exceptions, Diagonal Av. and Pere IV st. creates an interesting meeting point. (Fig. 34) Essentially, reclaimed water flows tangentially to Diagonal Avenue being interrupted at its intersection with Pere IV axis. The crossing point between the two vertebral axes is also the starting point of landscape and urban design by dividing the project into two main parts.

54

To B e WR sós P

Reclaimed water network

Sewerage network

Figure 32. Situation and water distribution scheme. Water is supplied from the Besós Regeneration Plant to the regulation tank. Then, water is distributed parallel to Diagonal Avenue to finally be returned to the sewer network.

DI

PER

AG

ON

AL

AV

.

st.

E IV

Figure 33. Main axes and geometry scheme. Intersection point becomes design articulator.

BAC DE RODA St.

ESPRONCEDA St.

BILBAO St.

EMILIA Y St. CORAN

I N T E G R A T E D P L A N N I N G . 22@ D istr ict, T h e

NewBlue Infrastructure Layer

BOLIVIA St.

MARROC St. (5) (1)

PERE

(4) (2)

IV St.

(6) (3) (7)

CRISTOBAL DE MOURA St. (8)

(9)

VENEÃ&#x2021;UELA St.

DIA GO

NA

LA v.

Figure 34. Site plan. (1) Semi-buried regulation tank and pneumatic waste collection, (2) Wooded area, (3) Low-staggered lake and bridge, (4) Open area, (5) Local police building, (6) Old factory building (7) Gardenning and orchad area, (8) Urban beach, (9) Bio-filtration and reception canal.

55

I N T E G R A T E D P L A N N I N G . 22@ D is tr ict, T h e

NewBlue Infrastructure Layer

Figure 35. Croisspoint view. Two large water bodies divide Poblenou’s Central Water Park: a stepped pond and a public square interpreted like an urban beach. Water consumed by water effects is biologically filtered and poured into the Diagonal’s canal to be returned to sewer network and be recycled.

On one side, a semi-buried regulation tank, surrounded by wooded area, a low-stepped pond about 20cm deep and a perpendicular bridge that connects its two extremes. On the other side, it is proposed an “urban beach”, a place where citizens can interact with water from different effects: a water sheet surface where users can lie down and be soaked; high water jets following different rhythms and forms and sprayed water clouds effects to provide extra humidity during sizzling Mediterranean summers.

Water used in this recreational area wolud be biologically filtered and spilled into a collection canal wich accompanies pedestrians along their walk through Diagonal Avenue. (Fig. 35) At the end of this canal, water cycle is closed by pouring water into the sewer network to be treated and re-used.

The Park’s project also includes landscaped areas, all irrigated with reclaimed water. First, a wooded area is planted in order to protect 56

and hide the regulation tank and the pneumatic waste collection system facilities. Then, is proposed a huge open area which allows a constant view of the lake and permit the users flow. For this area optimal irrigation would be sprinkler method during the early hours of the day. And finally, a gardening or orchard area with aligned trees that would remind field crops disposition. It could be used a dropwise method to this area.

According to this urban intervention Poblenou’s district will have a new sustainable park, without obstacles, resilient, inclusive and also would represent no extra water consumption for city water supply.

In conclusion, this proposal shows how to plan an integrated water cycle management with urban planned strategies.

water demand and the risk of evaporation do too, causing dramatic imbalances in its territorial water resources.

Coastal areas are most susceptible to these changes, which must be added negative effects caused by saline intrusion and pH soil change. Unfortunately, there are not only problems created by climate change, but political conflicts between certain territories sharing river basins are increasingly frequent. Therefore present and future water challenges face an uncertain future context yet.

5

CONCLUSIONS

Water is an element in constant motion, unpredictable and hard to contain. Furthermore, it is considered generator of life and its control represents success in our historical settlements.

Methods used along centuries of experience have created an enormous strategies background to take advantage of its innumerable benefits. Milestone methods like Persian qanats, egyptian shadoofs and south asian rain water harvesting systems represent the intense relationship between water and humanity since the beginning of our civilizations. Today, in a context of demographic exponential growth, especially in developing countries, searching for new sources of water it is essential to satisfy an optimal balance between water consumption and water demand.

Nowadays, more than 50% of world’s population lives in cities, predictions point to an increase up to 65% in 2050. Many aquifers around the world are being overexploited, exhausting their water resources due to the lack of surface water and scarce rainfall patterns. Global temperature increase have changed the natural water cycle, weather irregularities and drought periods are becoming more frequent. If temperature increases, both

59

This research has focused on how to develop an integrated water cycle management from an urban planner point of view.

Looking for new strategies for a more sustainable and rational use of water for our current and future cities design. But, it makes no sense to propose a sustainable water cycle to cities if is not take into account the large amount of water demanded outside cities. Agricultural sector consums around 70% of water sources in Catalonia. Considering the importance of agricultural sector in our economies, optimization of irrigation systems have a notable impact on total water consumption rates. Saving improvements occur both to improve infrastructure and modernize irrigation systems. Public administrators must provide to irrigation communities the tools and incentives needed to promote an efficient use of water.

Spain has an applicable legislation (RD 1620/2007) since September 2007 referred to recycled water uses and its sanitary requirements. It serves to give concessional tramitations, boost public initiative projects and has established reclaimed water quality standards for non-potable uses. Wastewater treatment facilities’ conversion in Water Reclamation Plants, such as the one available in El Prat de Llobregat or the one proposed in this research, el Besós Water Reclamation Plant, offers an important platform for research, development, innovation and public demonstration of high quality water production. It provides great potential benefits too, like the implementation of an effective solution to mitigate lack and reliability of available water resources in Barcelona’s metropolitan region during drought periods.

In addition, it achieves scientific, technological and managerial experiences in alternative resources that would offer huge advantages to solve similar situations that occur and will occur in both geographical areas European Mediterranean and Middle Eastern. Water regeneration public acceptance is essential for a successful implementation. As the engineer and reclaimed water guru, Takashi Asano, says “water should not be judged by its history but by its quality”, indicating that currently there is not enough to have excellent technical solutions but citizens information and participation processes are essential to achieve a higher degree of public acceptance around the world.

If we wish to live in smart cities, integrated water management is priority for urban planning future. Indirect potable reuse is applied for some years as an innovative concept in a few places in the world, such as southern California, Belgium, Singapore and Southeast Australia. Their common goal is to generate a more reliable source of public water supply to face weather irregularities using similar advanced regeneration treatments like coagulation, membrane filtration, reverse osmosis or reversed electrodyalisis.

The single major project in direct water reuse is located in Windhoek, the capital of Namibia. Windhoek is located in an area with many challenges to water quantity and quality. The climate is very arid and the city is surrounded by the Namib Desert and the Kalahari Desert. City water supplies relies on both surface water and groundwater reservoirs. In addition to very little water resources, city population has been increasing constantly throughout the past thirty years (at rate of 5% per year since 1990). Because of all these factors, the city was inspired to explore the option of direct water reuse, becoming a pioneer example for the rest of the world.

A planned cycle of recycled water is an essential component for integrated water resources research, especially in coastal areas where an optimal urban planning can contribute significantly to increase their net water resources. Reclaimed water offers a

61

far superior guarantee than conventional sources of supply, ensuring water flow availability, especially during summer seasons, and enabling pre-potable water to be used for urban supply and environmental requirements.

Usually wastewater treatment plants are located relatively close to large population centers, this fact facilitates the possibility to plan a closed water cycle for our cities in order to take advantage, a thousand times if it is necessary, of consumed water by the city itself.Therefore, it should no longer consider what is the real cost of reclaimed water but what is the real value of its cost in terms of energy consumption and sustainability.

Water reclamation process consumes 1 kWh/m3, while sea water desalination reaches values of 4 kWh/m3. Energy consumption corresponding to purification (regeneration and purification comsumption are similar to each other) is between 1.1 to 1.7 kWh/m3. To these cost should be added environmental impact created by carbon dioxide contribution, which is an increase of 0.01 €/m3 for reclaimed water and 0.04 €/m3 for sea water desalination.

Finally, after enumerating the huge amount of advantages of an integrated water city cycle this research has been proposed, as a practical example, the construction of a new reclaimed water network in Barcelona city. “The NewBlue Infrastructure Layer” is proposed in 22@ District, which is known as Barcelona’s innovation district in order to replace, in a first phase, nearly 300 million liters of drinking water with reclaimed water. Reclaimed water will be used for parks and gardens irrigation, ornamental lakes maintenance, street cleaning and fire extinguishing.

In addition, last chapter includes a water landscape proposal for Poblenou’s Central Park redevelopment project. Water would become protagonist accompanying pedestrians along their walk through the crowded Diagonal Avenue. The project also proposes an area conceived as an “urban beach” creating a collective urban space to interact with water.

LIST OF FIGURES Figure1. Fluvial Civilizations map. Made by the author (2015) Figure2. General Schematic for a Qanat. www.iranicaonline.org/articles Figure3. Qanat rows sequence. www.cais-soas.com/CAIS/Science/ aqueducts_iran.htm Figure4. Egyptian Shadoof. www.fineartamerica.com/products/ egypt-shadoof-irrigation-granger-greeting-card.html Figure5. Tambour. Based on Archimedes screw. www.fineartamerica. com/products/archimedes-screw-science-source-canvas/ Figure6. Berber region Saqia. Professor Randi Haaland. (1983) www.medievalsaiproject.wordpress.com/2011/05/05/ Figure7. Eastern Fluvial Civilizations map. Made by the author (2015) Figure8. Stepwells in Rajasthan, India. http://socks-studio.com /2014/03/13/inhabiting-infrastructures-indian-stepwells/ Figure9. Bathing Ghat in Banaras, India 1980. www.upload.wikime dia.org/wikipedia/commons/b/bc/Bathing_Ghat_Banaras Figure10. Circum-city lake-plan of Shangqiu. www.turenscape.com/en glish/news/view.php?id=169 Figure11. Balance scheme of groundwater in a soil column. Strahler A.

N., Strahler, A. (1989). Geografía física. (Eds.) Omega, S.A. Figure12. Water Resources Development - Summary Statistics for all

Regions. www.unwater.org/downloads/UNW_Status_Report_ IWRM.pdf Figure13. Global water demand in 2000-2050. http://unesdoc.unesco. org/images/0023/002318/231823E.pdf Figure14. The Five Principles for Sustainable Agriculture. www.unesco. org/new/en/natural-sciences/environment/water/wwap/ Figure15. World map of underground water resources and recharge.

(2012). WHYMAP - Webmapping Application.

Figure16. Annual water stress for present conditions and projections

for two scenarios. Climate change, impacts and vulnerability

in Europe 2012. EEA (European Environment Agency).

Figure17. Projected change in minimum river flow with return period

of 20 years. Climate change, impacts and vulnerability in Eu

rope 2012. EEA (European Environment Agency).

Figure18. Overview of WWTP of Baix Llobregat. www.life-wire.eu/index php/project/demonstration-site/ Figure19. Scheme of most used membrane processes for advanced

water treatment. http://triotirta.co.id/product-services/hy

dranautics-ultrafiltration-nanofiltration-reverse-osmosis/ Figure20. Reverse osmosis diagram. Made by the author (2015) Figure21. Network elements of reclaimed water. http://www.madrid.es.

UnidadesDescentralizadas/RelacionesInternacionales/Pub

licaciones/CatalogoBuenasPracticas/MedioAmbiente/1.

Creación%20Red%20Agua%20Regenerada%2014.pdf Figure22. Diagram costs of an integrated cycle of water consumption

in Madrid. According with rates set by the Canal de Isabel II

Management. https://oficinavirtual.canalgestion.es/recytal/

public/suministro_tarifas_bonificaciones.htm. Made by the

author (2015) Figure23. Example of an Integrated Water Cycle Management. Made

by the author (2015) Figure24. Current and proposed Barcelona’s reclaimed water network.

According with AMB (Barcelona Metropolitan Area) data.

Made by the author (2015) Figure25. Barcelona’s water consumption, distribution and demand

frequency on urban uses. Adapted from Barcelona’s water

consumption study from Environmental department Barcelo

na city Council. (2008) Figure26. The NewBlue infrastructure layer diagram. Made by the

author (2015) Figure27. Proposed reclaimed water network in South Diagonal Av.

Made by the author (2015) Figure28. South Diagonal Avenue infrastructural section. Made by the

author (2015) Figure29. Diagonal Mar Park view. http://compo3t.blogspot.com. es/2013/12/unos-mapas-de-deseos-enric-miralles.html Figure 30. Potsdamer Platz view. http://www.dreiseitl.com/index. php?id=82&lang=en Figure 31. Banyoles old town public space project. http://www.miasar quitectes.com/portfolio/banyoles-old-town/ Figure 32. Situation and water distribution scheme. Base image from

Google maps. Made by the author (2015) Figure 33. Main axes and geometry scheme. Made by the author (2015)

REFERENCES Figure 34. Site plan. Made by the author (2015) Figure 35. Crosspoint view. Made by the author (2015)

ACA (2008a). Bases per a un model de gestió de l’aigua a Catalunya 2007-2025. Departament de Medi Ambient i Habitatge, Generalitat de Catalunya.

L I S T O F TA B L E S

ACA (2008b). Aigua i canvi climàtic. L’energia al cicle integral de l’aigua a Catalunya: Diagnosi i Estratègies de Mitigació. Esborrany versió 3.3, febrer de 2008.

Table1. Fluvial Civilizations. Synergies Settlement-Fresh Water supply.

Made by the author (2015) Table2. Adaptation of operating diagram of the WWTP of El Prat

de Llobregat. http://perfil.amb.cat/web/emma/aigua/saneja ment/depuradores/depuradora_llobregat/dades_tecniques.

Table3. Reclaimed water uses allowed under the Spanish RD

1620/2007. Adapted from BOE (2007). RD1620/2007 Table4. Milestone events in the evolution of wastewater treatment,

reclamation, recycling, and reuse Adaptated in part from

T.Asano 2006. Water Recycling - A relevant solution? Chp.16 Table 5. Required investments, cost and power requirements to recy-

cle water. Adapted from Rafael Mujeriego conference. La ges

tió integrada de l’aigua: “l’experiència de quatre anys de se

quera a Califòrnia”. Barcelona, May 2015.

Table 6. Barcelona’s Water Parks comparison study. Made by the au-

thor (2015)

Ajuntament de Barcelona, Departament de Medi Ambient. El consum d’aigua a Barcelona, 2008.

Asano, T (1998). Wastewater Reclamation and Reuse. Vol. 10. CRC Press Technomic Publishing Company, Inc. USA. Asano,T (2006). Water Recycling - A relevant solution?, Chapter 16.

Water crisis: Myth or reality? Marcelino Botin Water Forum 2004.

Ed. P. Rogers, M.P. Llanas.

Beaumont, P. (1982) The hydrology and water resources of the Iranian plateau. Encyclopaedia Iranica, Online Edition. [09.07.2015] BOE (2007). Real Decreto 1620/2007, de 7 de diciembre, por el que se establece el régimen jurídico de la reutilización de las aguas depuradas.

Consejo Superior de Investigaciones Científicas, CSIC (2008).

Aguas continentales. Gestión de recursos hídricos, tratamiento y calidad del agua. Cyan Proyectos y Producciones Editoriales, Madrid.

ISBN 84-00-08454-3.

Dades Ambientals Metropolitanes 2007. (Ed.) Entitat Metropolitana de Serveis Hidràulics i Tractament de Residus (EMSHTR).2008 pg. 14-15 De Meulder, B., Shannon, K. (2008). Water and the city: the ‘great stink’ and clean urbanism. In: Shannon K., De Meulder B., d’Auria V., Gosseye J. (Eds.), Water urbanisms. Amsterdam: SUN, 5-9.

European Environment Agency (EEA) 2007. Climate change and water adaptation issues. EEA Technical report, núm. 2.

EEA, 2004. Impact of climate change, EEA Report No 2/2004.

EEA, 2012. Climate change, impacts and vulnerability in Europe

2012. EEa Report No 12/2012

Water Science and Technology, vol. 50, n. 2, 1-8.

IPCC, 2007: Cambio climático 2007: Informe de síntesis. Contribución de los Grupos de trabajo I, II y III al Cuarto Informe de evaluación del Grupo Intergubernamental de Expertos sobre el Cambio Climático [Equipo de redacción principal: Pachauri, R.K. y Reisinger, A. (directores de la publicación)]. IPCC, Ginebra, Suiza.

Shannon, K. South Asian Hydraulic Civilizations. India, Sri Lanka, Bangladesh (2008). UFO1 Water Urbanisms. Amsterdam: SUN

Jevons., W. (1888) [online database] The theory of political economy, Chapter IV. Library of economics and liberty. www.econlib. org [19.02.2015] Magrama: Ministerio de Agricultura Alimentación y Medio Ambiente (2007). Perfil Ambiental de España. Informe basado en indicadores.www.magrama.gob.es/es/calidad-y-evaluacion-ambiental/temas/ informacion-ambiental-indicadores-ambientales/indicadores-ambientales-perfil-ambiental-de-espana/perfil-ambiental-de-espana-2 007/. [17.11.2015] Mujeriego, R. (2015). Jornada sobre la recerca de sòls a Catalunya.

La gestió integrada de l’aigua: “l’experiència de quatre anys de sequera a Califòrnia”. Conferència 27 de maig de 2015.

Mujeriego, R. (2005). La reutilización, la regulación y la desalación de agua. Departamento de Ingeniería Ambiental. Universidad Politécnica de Catalunya (UPC) Mujeriego, R. (2009). Monogràfic. La reutilització planificada de l’aigua: de l’eficiència a l’autosuficiència. Universidad Politécnica de Catalunya (UPC) Mujeriego, R. (2013). Avances en la regeneración del agua y el ahorro de energía. Universitat Oberta de Catalunya (UOC) May 2013 OECD. (2012), OECD Environmental Outlook to 2050, OECD Publishing. http://dx.doi.org/10.1787/9789264122246-en Ramirez, R. (2000) Perspectivas del Medio Ambiente Mundial 2000.

PNUMA. Ed. Mundi-Prensa. Vivendi Environment. Annual Report Ramirez, R. (2006) La problemática global del agua. Monografías, S.A. Web archieve.

Sala, l.; Serra, M. (2004). “Towards Sustainability in water recycling”.

Strahler A. N., Strahler, A. (1989). Geografía física. (Eds.) Omega, S.A. USCB (United States Census Bureau). 2012. International Programs.

World Population. http://www.census.gov/population/international/ data/worldpop/table_population.php UN-Water (2008). Status Report on IWRM and Water Efficiency Plans for CSD16 WWAP (United Nations World Water Assessment Programme).

2015. Facing the Challenges. Case Studies and Indicators. Paris, UNESCO. WWDR, 2015. (World Water Development Report), UN-Water.

United Nations Educational, Scientific and Cultural Organization, March, 2015.

Yu,K. Li, D. Lei, Z. (2008). [online database] Live in the water: Flood adaptative landscapes in the Yellow River Basin of China. www.turenscape.com [10.07.2015]

Specially thanks to my husband and family for their unwavering support and confidence that they have induced in me; also to my tutor Miquel Corominas for teaching me with patience and wisdom.