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The Loreto region in Baja California Sur, Mexico is experiencing rapid growth in the tourism and
land development sectors. In light of this trend, planners are anticipating a parallel growth in
demand for potable water supply, which is already stressed in Loreto’s arid climate. According to
the Study for the region of Loreto, Baja California Sur, Mexico (Steinitz et al., 2005), the potential for water demand to
exceed the existing water resources in the region is probable without intervention. In response,
decision-makers are considering desalination technology as an option to supplement existing
potable water provisions. This paper investigates next steps for effectively managing Loreto's water
resources as well as the best practices of desalination technology in providing additional potable
water sources within the context of the Loreto Urban Development Plan.
The response to these challenges should be a combined effort including water conservation,
efficiency upgrades to existing infrastructure, augmentation of existing resources, and an
investigation of the feasibility of desalination facilities. Prior to pursuing desalination, it is essential to investigate the potential for better use and management of existing water resources. This
includes evaluating the potential for water conservation measures and quantifying the increased
water benefit realized from their implementation. The assessment of existing infrastructure should
occur in conjunction with conservation measures.
The process of desalinating seawater into potable water is not a new technology. A wide range of
methods exist for accessing saline water, removing salts, and disposing of desalination waste, each
process having impacts to the environment. Current methods used to intake water and to dispose
of waste brine can be intrusive to marine environments. Today, the preferred technology to
desalinate brackish and seawater is reverse osmosis (RO). Reverse osmosis technology persists as a
feasible desalination solution typically due to lower energy and land use requirements.
The products of desalination processes are a high-quality potable water resource and an extremely
saline, brine waste effluent. Many challenges are posed when integrating a desalination plant with
existing potable water infrastructure, but more difficult, is the sustainable disposal of the highly
saline waste stream. To date, saline effluents are discharged back into large bodies of water, usually
into the ocean. Disposal of desalination effluent in this manner poses a significant environmental
threat with regards to the unique marine life and habitat of the Loreto region.
This document lays out a set of desalination best practices that should be incorporated in the design
and siting of a desalination facility. There are no collective best practices for desalination in any
environment; rather best practices are site specific to each location's natural and development
constraints. The best practices for desalination technology should be based on site conditions, the
quality of water needed, the availability of engineering and construction resources, and the
potential impacts to existing water resources such as aquifers. At best practices should include
methods for intake of brackish groundwater, alternative methods for pretreatment, specific
desalinating processes, and brine disposal.
The Loreto region has specific constraints associated with siting a desalination facility. These
include the presence of the Loreto Bay National Marine Park and the location of existing water
supplies. Additionally, the existing infrastructure and rapid growth of the region accelerate the
potential development of individual desalination facilities. The community's application of best
practices and their understanding of how desalination will shape the future of the region will be
pivotal in determining Loreto’s future. |
