Hydro-economic analysis of water supply for the binational transboundary region of Baja California, Mexico

The northern border of Baja California hosts prominent agriculture and fast-growing cities under an extreme-arid climate. This paper provides an economic-engineering analysis of water supply alternatives to cope with agricultural, environmental and urban water needs projected to year 2025. Analysed alternatives include idealised water markets, wastewater reuse, seawater desalination and infrastructural expansions. Network flow optimisation using CALVIN (CALifornia Value Integrated Network) was employed. A database of the water system was built to include hydrology; agricultural, environmental and urban demands infrastructure, and economic information on operating costs and economic value of water. For the coastal cities, results show that wastewater reuse along with other already projected infrastructure expansions is overall the most economically promising alternative. Water markets offer leverage and flexibility for future urban needs. However, some locations cannot take advantage of domestic water markets with current aqueduct capacities. Worthwhile investments in infrastructure include an expanded aqueduct connecting coast and inland water supply systems. Furthermore, at current urban water prices and operating costs, seawater desalination is uneconomical for Baja California. Computer models are useful to better understand water-related issues in a region and provide a technical basis for developing and comparing long-term water management solutions.

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The application of economic-engineering optimisation for water management in Ensenada, Baja California, Mexico

Water Science & Technology ◽

10.2166/wst.2007.038 ◽

2007 ◽

Vol 55 (1-2) ◽

pp. 339-347 ◽

Cited By ~ 17

Author(s):

J. Medellín-Azuara ◽

L.G. Mendoza-Espinosa ◽

J.R. Lund ◽

R.J. Ramírez-Acosta

Keyword(s):

Water Management ◽

Water Demand ◽

Baja California ◽

Wastewater Reuse ◽

Wastewater Reclamation ◽

Seawater Desalination ◽

Management Options ◽

Promising Alternative ◽

Water Users ◽

Demand Models

Mathematical optimisation is used to integrate and economically evaluate wastewater reuse, desalination and other water management options for water supply in Ensenada, Baja California Mexico with future levels of population and water demand. The optimisation model (CALVIN) is used to explore and integrate water management alternatives such as water markets, reuse and seawater desalination, within physical capacity constraints and the region's water availability, minimising the sum of economic costs of water scarcity and operating costs within a region. The modelling approach integrates economic inputs from agricultural and urban water demand models with infrastructure and hydrological information, to identify an economically optimal water allocation between water users in Ensenada. Estimates of agricultural and urban economic water demands for year 2020 were used. The optimisation results indicate that wastewater reclamation and reuse for the city of Ensenada is the most economically promising alternative option to meet future water needs and make water imports less attractive. Seawater desalination and other options are not economically viable alone, but may have some utility if combined with other options for the Ensenada region.

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Stability Analysis of Urban Water Supply Systems with Wastewater Reuse.

Doboku Gakkai Ronbunshu ◽

10.2208/jscej.1995.524_121 ◽

1995 ◽

pp. 121-130

Author(s):

Haruhiko Watanabe ◽

Sheng Ping Zhang ◽

Norio Okada

Keyword(s):

Stability Analysis ◽

Water Supply ◽

Wastewater Reuse ◽

Water Supply Systems ◽

Urban Water ◽

Urban Water Supply ◽

Supply Systems

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Optimal Implementation of Wastewater Reuse in Existing Sewerage Systems to Improve Resilience and Sustainability in Water Supply Systems

Water ◽

10.3390/w13152004 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2004

Author(s):

Aakash Dev ◽

Timo C. Dilly ◽

Amin E. Bakhshipour ◽

Ulrich Dittmer ◽

S. Murty Bhallamudi

Keyword(s):

Wastewater Treatment ◽

Water Supply ◽

Wastewater Reuse ◽

Treated Wastewater ◽

Water Supply Systems ◽

Test Cases ◽

Decentralized Wastewater Treatment ◽

Graywater Reuse ◽

The Cost ◽

Supply Systems

A transition from conventional centralized to hybrid decentralized systems has been increasingly advised recently due to their capability to enhance the resilience and sustainability of urban water supply systems. Reusing treated wastewater for non-potable purposes is a promising opportunity toward the aforementioned resolutions. In this study, we present two optimization models for integrating reusing systems into existing sewerage systems to bridge the supply–demand gap in an existing water supply system. In Model-1, the supply–demand gap is bridged by introducing on-site graywater treatment and reuse, and in Model-2, the gap is bridged by decentralized wastewater treatment and reuse. The applicability of the proposed models is evaluated using two test cases: one a proof-of-concept hypothetical network and the other a near realistic network based on the sewerage network in Chennai, India. The results show that the proposed models outperform the existing approaches by achieving more than a 20% reduction in the cost of procuring water and more than a 36% reduction in the demand for freshwater through the implementation of local on-site graywater reuse for both test cases. These numbers are about 12% and 34% respectively for the implementation of decentralized wastewater treatment and reuse.

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Energy implications of the millennium drought on urban water cycles in Southeast Australian cities

Water Science & Technology Water Supply ◽

10.2166/ws.2017.110 ◽

2017 ◽

Vol 18 (1) ◽

pp. 214-221

Author(s):

K. L. Lam ◽

P. A. Lant ◽

S. J. Kenway

Keyword(s):

Water Supply ◽

Water Conservation ◽

Energy Use ◽

Water Supply Systems ◽

Urban Water ◽

Demand Side ◽

Related Energy ◽

Millennium Drought ◽

Wide Range ◽

Supply Systems

Abstract During the Millennium Drought in Australia, a wide range of supply-side and demand-side water management strategies were adopted in major southeast Australian cities. This study undertakes a time-series quantification (2001–2014) and comparative analysis of the energy use of the urban water supply systems and sewage systems in Melbourne and Sydney before, during and after the drought, and evaluates the energy implications of the drought and the implemented strategies. In addition, the energy implications of residential water use in Melbourne are estimated. The research highlights that large-scale adoption of water conservation strategies can have different impacts on energy use in different parts of the urban water cycle. In Melbourne, the per capita water-related energy use reduction in households related to showering and clothes-washing alone (46% reduction, 580 kWhth/p/yr) was far more substantial than that in the water supply system (32% reduction, 18 kWhth/p/yr). This historical case also demonstrates the importance of balancing supply- and demand-side strategies in managing long-term water security and related energy use. The significant energy saving in water supply systems and households from water conservation can offset the additional energy use from operating energy-intensive supply options such as inter-basin water transfers and seawater desalination during dry years.

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