(1.290 m). In the coastal area, the commune has two portions island called Isla Guamán (located in front of Caleta La Chimba, 23°33'00"S latitude and 70°25'00"W longitude) and Isla Santa María (located in front of Caleta Constitución, 23°26'00"S latitude and 70°37'00"W longitude). Hydrology There are about fifteen streams that have watersheds with accumulation of sand and gravel. Within the broader watershed (hoya) are the "Hoya La Chimba", "Hoya Caracoles", "Hoya La Cadena", "Hoya La Negra" and "Hoya El Way". These watersheds and their streams (Quebrada), such as "Quebrada sin nombre", "Quebrada Baquedano", "Quebrada El Toro", "Quebrada El Carrizo" and "Quebrada Jardines del Sur", which helped cause the flood of 1991. The coastal edge of Antofagasta is rocky and steep, so there are no natural beaches, the majority being artificial. Just north of the city, natural beaches extend to the areas of "La Portada", "Las Losetas" and "La Rinconada". Within the water resources of the commune, there are different dry lakes (salar), among which include the Salar de Pajonales, Salar Mar Muerto, Salar Punta Negra and the Salar de Navidad. Governance As a commune, Antofagasta is a third-level administrative division of Chile administered by a municipal council, headed by an alcalde who is directly elected every four years. As of 2021, the mayor is Jonathan Velásquez. Within the electoral divisions of Chile, Antofagasta is represented in the Chamber of Deputies by Marcela Hernando (PRSD) and Paulina Nuñez (RN) as part of the 4th electoral district, together with Mejillones, Sierra Gorda and Taltal. The commune is represented in the Senate by Pedro Araya (Progressive Convergence, 2014–2022) and Alejandro Guillier (Progressive Convergence, 2014–2022) as part of the 2nd senatorial constituency (Antofagasta Region). The township has three local police courts. In addition, the Municipality of Antofagasta has a number of municipal headquarters, which are entities created to meet and control certain community needs a more specific way. Economy Antofagasta's economic development is mainly based on copper mining and nonmetallic minerals such as nitrate and iodine. It is also important port activity, although in recent years has lost the lead port in the region, due to the installation of the megaport of Mejillones. Antofagasta owns two major industrial areas; one is located outside the urban area known as Ciudad Empresarial La Negra, a complex of approximately 2,400 hectares. There are refinery furnace copper industries in addition to cement, lime and other products. The second industrial