Guayas River Guayas DeltaRiver Urban Delta Water Urban Management Migration1
Landscape Urbanism Studio 2018
BINDI RADITYA PURNAMA
Urban Water Management in Guayaquil
Purnama, 2018
Investigation and Adaptation of Climate Change and Sea Level Rises through Spatial Configuration
Settlements claiming the estuary, Suburbio, Guayaquil
Abstract This paper focuses on the water in Guayaquil, Ecuador. The first part of the paper is about water issues happening in Guayaquil, such as tidal fluctuation, climate change, El Nino, sea level rises, water clogging, fresh water sources, and direct water discharge effect that causes pollution and low oxygen level and sinking aquifer. The second part is about case studies of projects that related to water management, such as a proposal for Fucha River in Bogota, Cheong Gye Cheon restoration project, and bioswale prototype in the University of California Davis. The last part of the paper is about a research by design that can be applied in Guayaquil, specifically in Puetro Liza, Suburbio, with the focus of dealing with water problems.
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(Google Earth, 2017)
(Masterplan Interagua, 2003)
Guayaquil 1961
Guayaquil 2017
Guayaquil and Water Issues Guayaquil is the largest and the most populous city in Ecuador, with around 2.69 million people in the metropolitan area, as well as the nation's main port. (Guayaquil, n.d.). The City of Guayaquil was founded in 1530 on the shores of the Estero Salado. Over the last few decades, the city has expanded dramatically and currently Guayaquil is the largest city in Ecuador. Urbanization presents a threat to the Estero Salado; the water is being contaminated with industrial and domestic wastewaters, garbage is being disposed of in the water body and the mangrove forest is being cut down and the shores occupied. Guayaquil has problem with water provision and sea water level, both current condition and future projected sea level rising. Both issues are linked and multiplying each other, including the change of river and salt intrusion.
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2.5 m 0m -1 m
Tidal Diagram
Photos of different tidal situation in the Estero Salado
El NiĂąo Southern Oscillation (ENSO) is a current of warm water that periodically flows along the Western coast of South America, usually with disastrous social and economic consequences in several areas of the littoral region and in all of Ecuador, including floods in cities, affecting water, wastewater and stormwater drainage systems, destroying highways, bridges, roads, agriculture, increase in sea level causing coastal erosion and an influx of debris to the beaches. (Aboussouan, 2003, page 9, retrieved from Witsenburg, 2007). The amount of water discharges was increased significantly in the event of El Nino 97-98.
3.5 m 0m
Purnama, 2018
Climate Change and El Nino
periodismoambientalucsg.wordpress.com
Seawater has different level throughout the day, according to moon table. In Estero Salado, the amplification is higher than normal sea. It fluctuates from -1 m from MSL to 2.5 m. (Stenfert J. , Bouman, Nolthenius, & Joosten, 2017) This affects the water transportation in a daily basis. Some of the big ships are not able to pass in the low tide situation due to high sedimentation in several spots in Estero Salado. (Barerra Crespo, 2016)
Purnama, 2018
Tidal Fluctuation
Studio Fieldwork, 2018
Sea Water and Flooding
El Nino Flood in Suburbio, according to a local settlement
El Nino in Guayaquil, 1997
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Purnama, 2018
Water Clogging In Suburbio, Guayaquil, some areas have a very low topography, close to the current sea level. Due to physics of water that always in the same level, sea water sometimes is filling up the existing drainage, and come out in the road, especially in the high tide and wet season.
2.5 m 0m Water Clogging Diagram
“Due to many reasons, sea level rise occurs on different time and spatial scales. Sea level rise can be divided into global and local sea level rise. Warming of the Earth causes water to expand and the glaciers to melt which both lead to global sea level rise. Although globally the sea level has been rising 3.5 mm per year since 1993, it differs locally due to subsidence, global sea level fluctuations, winds, ocean circulation and water density.� (Stenfert J. , Bouman, Nolthenius, & Joosten, 2017)
In Guayaquil, the rising of water level in Estero Salado is very apparent. According to a local resident in Suburbio, every year during the wet season, the flood can reach 40 cm from the road. It was not happening this frequent 10 years ago. There is also an assumption by local experts that analyses the land in Suburbio can be sinking because of lack of water in the aquifer.
4.5 m 3.5 m 2.5 m
Sea Level Rise +1m with El Nino
Sea Level Rise +1m with high tide
Purnama, 2018
Sea Level Rises
0m
Simulation of Sea Level Rise + 1m and El Nino
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Purnama, 2018
La Toma Water Plantation
Fresh Water Sources La Toma
Water Harvesting
Prediction of Salt Intrusion
Prediction of Salt Intrusion Purnama, 2018
Due to high rainfall in the wet season and lack of provided water by the government, local people are catching water from the rain and store it in a tank. This technique is very useful, especially in a remote place such as outside Daule city and in the Cerritos de Los Morenos.
Conventional Water Harvesting Practice in Ecuador
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Purnama, 2018
The main collection of the drinking water supply for the city of Guayaquil is approximately 26 kilometers north of the city. The drinking water facility ‘La Toma’ withdraws water from the Daule River and treats it. (Witsenburg, 2007) The facility is under threat of salt intrusion, now being prevented by Daule-Peripa Dam. (Stenfert J. , Bouman, Nolthenius, & Joosten, 2017) The salt intrusion is going stronger every year because of sea level rises.
Purnama, 2018
Direct Water Discharge Effect Pollution and Oxygen Level in Estuary Estuary contains a brackish water, a mix of salt water and fresh water. The direct discharge from urban run-off causes unbalanced oxygen level, that can threaten the ecosystem. Mangroves, on the other hand, is very useful to maintain the oxygen level. In Suburbio, mangroves have been cut off and changed into hard surface and settlements. Direct discharge of water also sometimes contains garbage that washed off from urban tissue to the estuary by a tidal wave.
Estuary Pollution by Settlements Purnama, 2018
Aquifer Although is not common for Guayaquil people to use well, aquifer level in Suburbio is suspected low and causing the land above is sinking. It happened because there is no water going to the aquifer because of hard surface and sewerage system that directed water flows to the estuary.
Aquifer Aquifer situation diagram
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www.plataformaarquitectura.cl, 2016
Case Study Fucha River, Bogota The offices MOBO Architects, Ecopolis and Concreta were awarded in Colombia the first place in
the public contest of ideas for the formulation of a strategic plan that addresses the Fucha river in an integral and multisectoral manner, one of the three tributaries that the Bogotá River has in the Colombian capital. (Valencia, 2016) The Fucha River is an urban canal that suffers the consequences of this separation between the city and life. The architect wrote that It is necessary to reconstruct these relationships through an alternative urban development that allows people to inhabit the river. (Valencia, 2016)
Illustration of the proposal
The river is in strategic location among multiple centralities, makes the river Fucha corridor an ideal place to promote a life-oriented development and sustainable urbanism. Densifying housing, ordering trade and cleaning the industry are the guidelines to follow. In the middle area of the corridor, considering the underutilization of the territory and its proposed networks, they promote urban revitalization through a strategy of low density and mixed use. The new density is compensated for by the creation of public spaces and micro-equipment in some of the current vehicular roads. (Valencia, 2016)
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www.plataformaarquitectura.cl, 2016
The river and its natural systems are the backbones of their proposal. It weaknesses should be problems for the city and its inhabitants. Restoring it will allow the consolidation of a territory that integrates urban life with the ancestral ecosystem of the Bogotá savanna. (Valencia, 2016)
Reactivating river
www.plataformaarquitectura.cl, 2016
Master plan of Fucha River
In the recent urban developments, the low occupation of the land and the absence of commercial activities have resulted in fenced sets that turn their backs on water and life. They propose an architectural intervention to return the activity in front of the river and a landscape intervention to re-link life to the ecosystem. (Valencia, 2016) In the areas destined for new developments, they propose a type of city that is friendlier with life in the public space. Equipped neighborhood centers, commerce on the first floor and the eyes of its inhabitants on the street, make this a safer place. The height of the buildings decreases as it approaches the river, forming a favorable space for the proper development of natural systems. (Valencia, 2016) Through a network of green links, they connect the neuralgic points of the sector, such as facilities, parks, squares and nodes of metropolitan scale, to then achieve a transition between the urban transport system and a new development oriented to sustainable transport. These links prioritize the pedestrian, the urbanism of proximity and expand the area of ​​influence of the natural systems of the river. (Valencia, 2016) The sum of the proposed strategies will serve to configure a true urban ecosystem. (Valencia, 2016)
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seoulsolution.kr
Cheong Gye Cheon Restoration Project
Before Highway
Seoul is a capital city of South Korea with the population over 10 million people. In the old map of Seoul, Chong Gye Cheon was a main artery of the creek goes to the settlements. It was filled up and became a highway in 1990, as a solution of the creek that was very polluted by the local settlements. After several years, the district became dense with over 6,000 buildings and over 100,000 small shops. It became a nation’s biggest commercial area. But until 2002, since the highway started, CBD redevelopment stopped, population and employment reduced, and business headquarters moved to other areas. So, in 2002, the government decided to do this restoration project. The government believed that the restoration project can shift the paradigm of urban realm and management, while it also recovers the history and culture. The landscape concept is a gradual sequence from history, to culture and urban, and to nature, from west to east. It also includes reviving old bridges that were destroyed for the highway. For transport alternatives, they proposed to discourage driving cars to the city center, instead they improve public transport system.
After Highway (1990)
After Restoration (2005) Situation of Cheong Gye Cheon through time
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seoulsolution.kr
Thermal analysis inside the project and nearby street
As a result of this project, in 2005, several benefits have been evaluated. For traffic jam, it just worsened a bit. The number of cars in and out reduces by 18%, while the public transport users increased by 13%. The air quality is improved, water quality is improved, noise level reduced, heat island effect relieved, and wind corridor is created. For ecology factor, the number of fish species is increased to 14 from 3, 18 species of birds are inhabiting here, and more than 40 species of insects detected. (In-Keun, 2006) Now, Cheong Gye Cheon is one of most visited tourist spots in South Korea.
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(Xiao & Mcpherson, 2011)
Bioswale Prototype, University of California Davis The study site was located at the University of California Davis (UCD) campus. The campus is in the heart of the Central Valley, between the Coast Range to the west and the Sierra Nevada to the east. The climate is Mediterranean, summers are sunny, hot, and dry while winters are wet but not cold, it rarely snows. On average, 90% of the average annual precipitation 446.0 mm occurs between November and April. Moisture comes from the southern side of the study site (i.e. Pacific Ocean) owing to the influence of mountain ranges. The Sierra Nevada Mountain Range blocks moisture from the east. The soils of the study region are varied from loamy soils to heavy clay soils. The study site was in the southwest corner of parking lot 47A at the intersection of La Rue Drive and Dairy Road. The micro-topography of the parking lot was elevated and slightly sloped toward north and south sides for drainage. Runoff from the south side of the lot drained into the peripheral landscape along La Rue Drive, with overflow draining into the street. (Xiao & Mcpherson, 2011) Field installation. Photos were taken at different stage of the field installation. a) Before the bioswale installation, b) excavated pit, c) filled with engineered soil, d) compacted the soil, e) leveled the pit, f) tested the soil settlement, g) added tree to the system, h) finished site, i) both control and treatment sites were coved with mulch to match the surrounding land cover.
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(Xiao & Mcpherson, 2011) Bioswale design
A treatment site included eight parking spaces and a buffer strip between the parking spaces and the bioswale. The north edge of the treatment site was the ridge of the parking lot where surface runoff was naturally divided to flow either to the north or the south. A native soil was excavated and replaced with engineered soil to form the base of the bioswale. A fine graded nonwoven geotextile was placed at the bottom, sides, and top of the engineered soil. The geotextile prevented fine soil/sediment from entering the system and reducing the system’s porosity. During soil replacement, the engineered soil was packed with a tamping rammer liter Bloodgood London Plane tree was planted in the center of the bioswale. (Xiao & Mcpherson, 2011) Field experiment results indicate that the bioswale effectively reduced the amount of storm runoff and pollutant (i.e. minerals, metals, organic carbons, hydrocarbons, and solids) loading from the parking lot. The bioswale reduced runoff by 88.8% and the total loading by 95.4%. Individual water quality constituent reduction rates ranged from 86% for iron to 97% for nitrogen. Pollutant removal rates for minerals, metals, organic carbon, and solids were 95%, 87%, 95%, and 95%, respectively. The high porosity of the engineered soil provided more space to store runoff and better aeration to the tree root system with the compacted clay loam soil at the control site. (Xiao & Mcpherson, 2011)
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Zona al sur de Guayaquil-Mapa 1955 Google Earth, 2017
Research by Design
Position of Puerto Liza in 1955
Site Location: Puerto Liza In the 20th century, there was a port called Puerto Liza by the end of the branches of Estero Salado, that connects the city with all ports along the estuary. The port now is buried and filled with an artificial land. The importance of small port is necessary to have for the city, according to the bigger concept for Suburbio as an urban archipelago, became the reason of reviving Puetro Liza.
Proposed position of new Puerto Liza
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Zoom Earth, 2017
KUL Studio Landscape Urbanism, 2018 Suburbio Urban Archipelago Concept
Study site area
Water Problem as Spatial Guide The old creek that was filled with land is having trouble with water clogging, due to a very low level that is below the fluctuate tidal situation of the estuary in a daily basis. In some extreme condition, the water filled up from the existing drainage that discharges to the estuary. Because of this problem, the Puerto Liza project is proposed to be built by relocating the existing settlement to higher land. The old creek is brought back by digging the artificial land, and put it aside, to create higher topography along the creek. This strategy is to deal with the problem of sea level rising and extreme condition such as El Nino. The topography proposed is as high as 10m from current sea level, so it can hold up sea level rising plus El Nino in 2100. In this proposal, the edge of the estuary is proposed to be filled again with mangrove. The mangrove will help control the salt and oxygen
level in the estuary, as well as bringing back estuary ecosystem. Because the shore is becoming mangrove, it became limited for the human to interact directly with the estuary, especially discharging water directly. Learning from water clogging issue, having drainage that discharge to the estuary has become apparent that is ineffective. So, the proposal is to introduce alternative discharging methods such as bioswale and retention pond. The placement of bioswale is using the existing grid. The existing grid is analyzed superabundant, that also contributes the urban heat island because of the asphalt surface. Bioswale is a gently sloping vegetative swale designed to slow and reduce storm water runoff while filtering out pollutants.
The water that goes to bioswales are water that comes from rain and from settlement daily uses. It can’t be too contaminated, so the water still needs to go to septic tank first before hits the bioswale. For heavy rain, bioswale cannot contain too much water, so the water can be over sometimes and need to be directed to a retention pond. The placement is using the existing urban tissue with lower land level from the surrounding, so the water from bioswale can be naturally flowing to it. Both bioswale and retention pond changes the direction of discharging from estuary to aquifer. This can prevent soil sinking that was happened because of lack of water in the aquifer.
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Water Clogging Issue
Sea water in high tide state infltrate the land from existing sewage system
Housing Typology
Existing Condition
+3.5m - El nino + High tid
Solar Roof
+2.5m - High tide +0.0m - Sea Level
Urban Farming
-1.0m - Low tide
Raised Topography
To protect city from water infiltration
Open Ground
For flexible mobility
Proposal
+4.5m - El nino + High tid
5-storey max
+3.5m - El nino + High tid
Avoiding elevator
+2.5m - High tide +0.0m - Sea Level -1.0m - Low tide
New creek alignment
digging from low land area
Natural Water Edge
For regrowing mangroves and protection for water from settlements
Proposed Topography
Existing Topography
Puerto Liza Design Concept Water Waste Collection Point
Adapting building typology with Water Potential Because of the strategy is involving the relocation of existing settlements and future population growth, densification is needed. One of the strategies is to rebuild existing blocks into new building typology. The building can be 4-5 stories with open ground, to be more permeable and floodable situation. The roof can be used for urban farming, and to collect
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rain water and to store it into water tank in the upper floor. The water can be used for daily usages such as plumbing and laundry. Using rain water in Guayaquil is effective since they have high rainfall in wet season, and the source of current water in La Toma is having a threat of salt intrusion that needs to be moved into other location. The waste water of the building will use a local septic tank, and the water after it can be flown into the bioswale.
Puetro Liza
New Port for small scale water transportation
Maritime Academy Promoting local water human resources
Market
Water Harvesting Roof Tank
Using potential of high precipitation throughout the year
de
Daily Use
to reduce the only consumption from regional water source (La Toma)
Septic Tank
Purnama, 2018
Water Management
No Discharging To Estuary
Bioswale
Filtering and infiltrate water to aquifer
de + Sea Level Rises year 2100
de
Retention Pond
Excess water from bioswale will be filtered here to infiltrate to aquifer
Aquifer
To prevent land sinking
Housing, Relocation
Relocation for settlements that has been moved because of proposed creeks and natural corridor
BRT
Retention Pond
For excess water from bioswale, to drain it to aquifer
Bioswale
Transforming from existing asphalt infrastructure
Incremental Existing Growth
Conclusion Climate change is not only affecting only the rising of sea level, but also other problems such as salt intrusion, sedimentation of the estuary and river, and unpredictable rainfall that can change the water sources. In case of Guayaquil, the issues that related to water such as lack of aquifer and damaged ecosystem of the estuary are mostly caused by human intervention. The strategies of dealing with water issues can be more adaptation instead of prevention in terms of spatial configuration, such as creating soft edge and topography adjustment. Soft engineering is showing more promises to create balance and sustainable environment.
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Bibliography Abdulla, F. A., & Al-Shareef, A. W. (2009). Roof rainwater harvesting systems for household water supply in Jordan. Desalination, 243(1-3), 195-207. Barrera Crespo, P. D. (2016). Delft3D Flexible Mesh modelling of the Guayas River and Estuary system in Ecuador. Biswas, A. K., & Tortajada, C. (2018). Assessing global water megatrends. In Assessing global water megatrends (pp. 1-26). Springer, Singapore. Guayaquil. (n.d.). Retrieved 5 31, 2018, from Wikipedia: The Free Encyclopedia: http://en.wikipedia.org/wiki/Guayaquil In-Keun, L. E. (2006). Cheong Gye Cheon Restoration Project. Prominski, M., Stokman, A., Stimberg, D., Voermanek, H., & Zeller, S. (2012). River. Space. Design: Planning Strategies, Methods and Projects for Urban Rivers. Walter de Gruyter. Stenfert, J., Bouman, R. R., Nolthenius, R. T., & Joosten, S. (2017). Flood Risk Guayaquil: A critical analysis on inundations. Retrieved 5 31, 2018, from http://resolver. tudelft.nl/uuid:267caf81-5af3-4f0c-9c6a-e4f01571019b Valencia, N. (2016, January 27). MOBO Architects + Ecopolis + Concreta diseñarán la estrategia de intervención para el río Fucha en Bogotá . Retrieved from plataformaarquitectura: https://www.plataformaarquitectura.cl/cl/781048/mobo-architects-plus-ecopolis-plus-concreta-disenaran-la-estrategia-de-intervencion-para-el-rio-fucha-en-bogota Watson, D., & Adams, M. (2010). Design for Flooding: architecture, landscape, and urban design for resilience to climate change. John wiley & sons. Witsenburg, F. (2007). The tragedy of the Estero Salado, Opportunities for Better Management. Retrieved 5 30, 2018, from https://repository.tudelft.nl/islandora/ object/uuid:fdf8edc0-e139-4e3c-96ae-b0ca73113161/?collection=research Xiao, Q., & Mcpherson, E. (2011). Performance of engineered soil and trees in a parking lot bioswale. Urban Water Journal, 8(4), 241-253.
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