The National Museum of Underwater Archeology (Arqua) of Cartagena has a problem with water, which will force it to close for six months to try to solve it. Since its inauguration in November 2008, the building that houses 600,000 Las Mercedes coins (the famous treasure of oddysey case) and the oldest ship on the planet (a Phoenician ship, from the 7th century BC found in Mazarrón) has suffered problems of dampness and water seepage in the basement, dedicated to exhibitions. A report prepared in 2019 by the technical secretary of Infrastructure and Equipment of the Ministry of Culture, to which EL PAÍS has had access, describes the situation as a “collapse” and raises [EN 2008]the need to create a maintenance protocol to reduce the water that threatens the viability of the center.
The origin of the problem lies in the conception and execution of the museum: the exhibition rooms in the basement were built more than four meters below sea level on land gained from the Mediterranean. The intention was to include a transparent surface on the ground to contemplate the seabed. It was not built and, according to the report, “the pressure exerted by the oceanic mass of the port at a higher level” causes water penetration pathways. The document concludes that the exhibition hall on the lower floor suffers an “irremissible flood.”
The most serious error that reveals the report, which was commissioned with a view to tendering the leakage repair work, is the execution of concrete underwater screens, of a thickness of 150 centimeters. These should ensure the tightness of the “bathtub” in the basement, but they do not work. The seawater passes through the concrete “due to the cracks left by its irregular execution”.
The museum, which was built by FCC and designed by the architect Guillermo Vázquez Consuegra, cost 20.3 million euros. According to the report, the origin of the damage of the building is in “the construction process”, since it was possible to contain the flow of water with the concrete slabs, but “the complete tightness was not achieved and leaks continued to be observed”. In fact, 15 liters of water per second were filtered during construction to the concrete vessel.
Embers on the fire
Then a drainage system was improvised to evacuate the waters “throughout the life of the building” through a network of canals, which surrounds it and that have collapsed by salt, such as stuck arteries. The water overflows the pipes and emerges in the exhibition hall and on the facade. As if that were not enough, this process is favored by the design of the air conditioning circuit, which permanently blows carbon dioxide into the network and multiplies the salt deposits. “It’s like blowing on the coals to fan the fire,” says the report.
“The drainage system had to work initially well, but shortly after the inauguration of the museum, moisture problems began to be detected in the basement, reaching percentages of relative humidity in the environment very high and harmful to the conservation of the exhibits,” he says. the technician of the Ministry of Culture.
The increase in relative humidity values (which favor the appearance of microorganisms, fungi and bacteria in objects and corrosion in metal parts) is also caused by roof leaks (collected with cubes) and by torrential rains. The museum is on a stone paved esplanade, where no rainwater collection grids were made. On days of heavy rain, the slope pours water against the walls of the building and seeps into the basement.
Carmen Jiménez, deputy director general of the State Museums, downplays the term “collapse.” “It’s just a word,” he says. Ensures that continuous maintenance work has been applied and that there is no evidence that archaeological objects have suffered. Although he does not question the design of the museum, today he does not believe that something like this would have been done. “It was a very delicate work, but the equipment is what it is and now we have to apply solutions,” he adds. The deputy director acknowledges that the torrential rains of recent years also do not help keep humidity under control.
The repairs will cost 280,000 euros, but the memory elaborated for the works of repair of the leaks is not very encouraging with the future of the institution through which 107,407 people passed in 2019 (since the arrival of the treasure of La mercedes has almost doubled his visits). Measures will be taken to reduce the formation of salt deposits in pipes that prevent evacuation, although “they have not been completely eliminated and, henceforth, although to a lesser extent, it is foreseeable that they will continue to be produced.”
The works in the basement, which will begin in a few months, will last half a year and will force the transfer of objects (the most sensitive and the largest) while operating on walls and floor. The masons will clean the salt that clogs the arteries, “but it will not have prevented the entry of water that the pressure of the sea will continue to cause,” says the technical report.
Arqua sources explain to EL PAÍS that the Ministry knows the delicate situation from the beginning (it was inaugurated in November 2008), but it was in 2014 when they responded to the alarms issued from the institution and initiated the investigation.