Agua Negra Pass Explained

Paso de Agua Negra
Elevation M:	4780
Location:	Argentina–Chile border
Range:	Andes
Coords:	-30.1922°N -69.8183°W
Map:	Argentina

The Agua Negra Pass (Spanish: Paso de Agua Negra) is a pass over the Andes mountains which connects Argentina and Chile. The highest point of this pass is at 4780m (15,680feet) AMSL.^[1]

Agua Negra Tunnel

To improve trade between Chile and Argentina, a 14 km, three-bore vehicular tunnel (two for traffic and one for ventilation) below the pass is planned, which will allow year-round traffic.^{[2] [3]} (The pass is closed for much of the winter.)

In March 2015, Argentina officially approved the project.^[4] It is awaiting ratification from Chile.

In 2018, the bidding contest for the tunnel project between construction companies took place. The whole project was budgeted at 1.5 billion dollars.^[5]

Also planned for the deepest part of the tunnel is the Agua Negra Deep Experiment Site (ANDES) (ANDES):^[6] an underground laboratory. Because all currently operating deep underground laboratories are located in the Northern Hemisphere, a Southern Hemisphere site would have some unique benefits:

• Combined with existing neutrino detectors, a longer baseline would allow more accurate localization of sources in neutrino astronomy, and
• When searching for dark matter, there is expected to be a seasonal variation due to the Earth's motion around the Sun. But such a signal could also be an error, caused by some subtle seasonal effect. Confirmation from a location with opposite seasons would rule out such an error.

ANDES is not expected to be ready before 2027.^[7]

See also

• Elqui Province, Chile
• San Juan Province, Argentina

Notes and References

1. Web site: PASO INTERNACIONAL "SAN FRANCISCO". gendarmeria.gob.ar. Gendarmeria Nacional Argentina. 26 February 2015. https://web.archive.org/web/20150227013326/http://www.gendarmeria.gob.ar/pasos-chile/agua-negra.html. 2015-02-27. dead.
2. News: Andes link a priority for Chile-Argentina-Brazil . December 2011 . Peter . Kenyon . TunnelTalk . 2015-04-25.
3. Web site: Agua Negra Tunnel . 2015-04-25.
4. Web site: Argentina Approved Construction of Tunnel Agua Negra to Join Chile . March 23, 2015 . Latin American Association of Ports and Terminals . 2015-04-25.
5. Web site: Agua Negra Tunnel - Verdict Traffic . 2023-12-01 . www.roadtraffic-technology.com.
6. Web site: The ANDES laboratory: Proposed laboratory design . 2015-04-25.
7. Ianni . Aldo . Status of Underground Labs . 27 July 2017 . XV International Conference on Topics in Astroparticle and Underground Physics (TAUP2017) . http://taup2017.snolab.ca/ . Sudbury, Canada . 2017-10-14.