Siglo In 1908, under the government of Colonel Carlos Sarmiento, a law was passed on August 25, which designated the area of present departments Rivadavia, Zonda and Ullum, under the name of Rivadavia, to give honor to former president. Also the same day and year, establishing the department Sarmiento, suprimindo Guanacache old jurisdictions and Flint, only to be districts in 1928, passed a new law of Municipalities, said that included the area within the department Rivadavia Capital . In 1931 he won the election Federico Cantoni. The railroad was opened J chal Department. Federico Cantoni, governor of the province, on two occasions. In 1935, the area known Rivadavia, Capital separated from the department and the area known as Zonda Rivadavia to finally begin building a new department. Is also recognized as a separate department Fertile Valley and establish the current limits.In 1936, he opened the bridges over the Rio San Juan, communicating Caucete departments, and Calingasta Albard n built with iron brought from Europe. In 1940, we present the first report on the importance of Ischigualasto. Begin to visualize the early works of industrial production as olive oil. On September 9, 1942, the law establishing the department Rawson, with Villa Krause, the head. Also on September 19 definitely establishing the department Rivadavia, setting the current limits and also created the department July 9, having been separated from Pocito. The former South Angaco Department is changing its name to the current department of San Mart n and the municipal organic law of September 4 was set definite limits Zonda department, being the village head, Villa Basilio Nievas in a small town that reminds one of the first settlers.In 1944, there was an earthquake measuring 7.8 Richter magnitude scale and a maximum intensity of IX grade modified Mercalli scale. The epicenter was located 20 kilometers north of the city of San Juan, near the town of La Laja, in the department Albard n. Be the earthquake of January 15 was the greatest tragedy to remind the people of Argentina. There is talk of 10,000 dead, an even greater number wounded, the almost total destruction of a city. On June 25, 1966, the provinces of San Juan and Mendoza signed an Interprovincial Boundary Agreement, which left the entire border demarcated between the two provinces. The limit was set by National Law No. 22 200 issued by the military government and published in the Official Gazette on March 27, 1980. Decree-Law No. 18 004 issued by the military government on 23 December 1968, established the boundaries between the provinces of La Rioja and San Juan.Previously, the military inspectors of both provinces entered into an agreement on March 12, 1968, in order to end a dispute secular boundaries. On December 21, 1973, the Legislature passed the law in La Rioja province No. 3468 disregarding the validity of Decree-Law of the military government. The government of San Juan passed in January 1969, the provincial law No. 3580, ratifying the interprovincial agreement signed by the military inspectors in 1968. The dispute centers on the glacier and Cerro El Potro “with potential mining copper and gold, where the Decree-Law No. 18 004 sets the limit starts from the Cerro El Potro, going from there south-easterly direction up to the Rio Blanco, but does not say what the southeasterly direction angle, so the area is enclosed but not demarcated. 1972, he organized the first National Festival of the Sun in 1973, establishing the Universidad Nacional de San Juan. On November 23, 1977 at 6:25 pm, San Juan again shook for telluric forces.An earthquake measuring 9 on the Mercalli scale or 7.4 degrees on the Richter scale, was the epicenter of Sierra de Pie de Palo and affected departments Caucete, May 25, July 9, San Martin and Angaco. Across the country felt the quake, long duration, which caused 65 dead and 300 wounded, destroying many buildings, almost all built without regard to earthquake standards, “in the city of Caucete and severely affecting agricultural activities Valley east of Tulum. In 1980, the work was finally inaugurated Ullum hydroelectric dam. Benefiting broadly to agriculture, causing a growing increase in acreage. In 1984, the department Rawson city is declared, based in Villa Krause. As one of today’s most important cities of the Great San Juan, where he developed an intense commercial activity. In 1994, finally ceased to circulate the passenger trains. In 1998, he began to execute the works Caracoles hydroelectric dam.