Mexico is in a critical situation regarding the use of its water resources due to overexploitation, pollution and misuse of water sources. The poor quality of the aquifers has caused the population to distrust the running water and resort to the consumption of bottled water. In the political sphere, the scarce access to water has become a source of conflicts between communities around the world.
Although in 2012 the fourth constitutional article was reformed to include the human right to access, disposal and sanitation of water, the reality is different. According to figures contained in the book “Water in Mexico. Actors, sectors and paradigms for a social-ecological transformation”, published by the Friedrich-Ebert-Stiftung Foundation, 12 million Mexicans have no access to drinking water and 80 percent of the bodies of water is contaminated with industrial discharges.
Dr. Judith Domínguez Serrano, academic coordinator of the doctorate in urban and environmental studies at El Colegio de México (Colmex), indicated that there are several problems, including legal ones, that must be resolved in order for the fourth constitutional article to be complied with. He emphasized the need to have a law that indicates how and in what period of time the human right to water will be fulfilled, in addition to the need to define whether this new law will replace the National Water Law or not.
Despite the shortage of water, in Mexico City people spend an average of 366 liters per person per day.
In 1960, desalination began in Mexico through distillation, but the oil crisis made the production of water more expensive through this process.
Thus, the first desalination plant was located in Baja California, considered one of the largest worldwide with a capacity of 320 liters per second (lps), 27,648 m3 / day.
Since the 1960s, due to the increase in population, shortage of surface water in Mexico, reduction of groundwater and deterioration of its quality, water resources have been limited. That is why from the 70s until 2000 there was a boom of desalination plants for tourist complexes and for the purification of bottled water. In 2003, the Maquilalas Tetakawi desalination project was completed, with a production of 11.76 lps (1,000 m3 / day), for industrial use. The same year, the project of a plant with a capacity of 200 lps was started in Cabo San Lucas, Baja California.
In 2001, IMTA identified 171 plants, of which 51 did not operate due to high costs and lack of qualified personnel and maintenance. The states with the most plants were Quintana Roo with 76 (44.4%) and Baja California Sur with 38 plants (22.2%). Most were for hotels and tourism service providers.
In 2001, the operating capacity was 52,455 m3 / day, which represented 77.7% of the maximum installed capacity that year, 67,487 m3 / day.
Because Ensenada and Tijuana are in an active zone in agriculture and the groundwater presented intrusion of seawater, in 2004 they began evaluating alternatives to build desalination plants. In 2005, desalination was established in Guaymas-Empalme and Puerto Peñasco in Sonora.
In 2006, the largest municipal plant in the country was built in Los Cabos, which produces 200 lps of water (17,280 m3 / d) and supplies part of Cabo San Lucas.
In 2007, the IDA had 435 plants in Mexico, of which 282 were in operation. It was reaffirmed that Quintana Roo and Baja California Sur had the largest number, 124 and 73 respectively. Reaching a national installed capacity of 311,376 m3 / d (3,600 lps).
Reverse osmosis is the most used system: it represents 76% of the desalination plants. In 2012, Mexico began the process of defining an official standard for desalination.
Mexican legislation establishes that the interior salty waters, the territorial sea and the brackish waters are public domain. Thus, the activities related to desalination, according to the Law of National Waters, require a concession.
Regarding desalination, the legislation does not mention it. Likewise, federal agencies with powers to regulate desalination have not established a norm to regulate the intake works, the disposal of brine discharges and the impact on the environment.
Therefore, in 2012 Mexico began the process of defining an official standard but has not yet reached its conclusion. Despite this, there are desalination projects to supply populations in the Northwest of Mexico. The installed flows vary from 2.2 to 4.4 m3 / s.
Desalination in Mexico is not a new practice; however an inadequate implementation has not allowed it to be a viable option in the long term.
The problems remain in force: the lack of regulation causes conflicts between suppliers, users and authorities, and causes problems of environmental impact and abandonment. It is urgent to define the regulatory framework.
Hotels and tourist services have been pioneers, and the first to have abandoned infrastructure. Institutional support to strengthen the tourism industry can be a viable alternative.
Recently, operators of drinking water services have opened a gap in the construction of desalination systems with competitive rates. The costs are already less than 1USD, which makes this source of water attractive.
Desalination is the appropriate alternative for many parts of Mexico, but requires a policy that allows it to be developed not only for tourist activities and larger populations, but also for industrial, agricultural, livestock and aquaculture production in areas with water scarcity and which will face more conflicts by supply.
The tools, technology and scientific advances to achieve it will be discussed at the Conference and Exhibition “Desalination in Latin America” that will take place in Santiago, Chile on March 6 and 7, 2019.