The Dirección Regional de Obras Hidráulicas (DOH), the regional hydraulic works directorate in Antofagasta, has gone more than 23 years without updating or approving the city's Plan Maestro de Evacuación y Drenaje de Aguas Lluvias (stormwater drainage master plan). That was the conclusion of the Contraloría Regional de Antofagasta in Final Report No. 440 of 2026, which audited flood and mudflow control works along the region's coastline.
According to Diario Financiero, the review covered construction and maintenance contracts carried out in 2024 and 2025 in Antofagasta, Tocopilla and Taltal. Taken together, the projects exceed $10 mil millones in public funds.
The Contraloría General de la República (CGR) is the autonomous body that audits the use of public funds and the legality of acts by the state administration. Its regional office found that, without an approved plan, there is no official definition of the primary and secondary stormwater drainage networks. That gap affects investment planning and prioritization.
The agency will open an administrative inquiry (procedimiento sumarial) to determine any administrative responsibility. It also gave the DOH 60 business days to report progress on the update and the committed timeline for its formal approval.
The audit also identified homes and settlements built on top of flood-control infrastructure or in risk areas. They include the informal settlements (campamentos) Niños Felices II, Sol y Luna, Flor del Norte, Camino Viejo and Pirámide Alta, as well as houses located at the bottom of the Tres Puntas ravine.
According to the report, these occupations sit in zones meant to channel mudflows or subject to building restrictions. The Contraloría flagged failures in oversight and coordination among municipalities, municipal works departments, the Secretaría Regional Ministerial (Seremi) de Vivienda y Urbanismo, the regional office of the housing ministry, and the presidential delegations. The agencies reported actions taken but did not demonstrate that the cases had been resolved.
In the La Cadena and Salar del Carmen ravines in Antofagasta, auditors found waste piled up in settling ponds, service roads and tributaries. The affected stretches reached about 2.8 kilometers in La Cadena and up to 5.2 kilometers in some Salar del Carmen tributaries.
The Municipalidad de Antofagasta acknowledged during the audit that it had no plan to inspect and clean those works. The Gobierno Regional (regional government) later removed waste, but a new review in August 2026 found the buildup persisted. The municipalities of Taltal and Tocopilla also failed to show formal cleaning mechanisms.
In the contracts, the Contraloría found that the government inspector for the works in the Caliche ravine, northern tributary, did not apply in time a fine for a 120-day delay in setting up the inspection office. The penalty amounts to 360 UTM (unidades tributarias mensuales, a Chilean inflation-indexed monthly tax unit), equivalent to $25.8 millones at September 2026 values.
The DOH acknowledged the omission and notified the contractor of the fine, though payment was still pending at the time of its response. The report also noted work paid for without sufficient documentation under a comprehensive maintenance contract, as well as an unauthorized perimeter fence and road in tributary No. 2 of Salar del Carmen.
After the rains of August 17 and 18, the Contraloría inspected ravines including El Toro, Cortaderas, Tipias, 5 de Octubre and Tres Marías. The infrastructure was operational and showed no significant damage. The DOH now has 60 business days to prove the fine has actually been collected.
