Semantok Dam Nganjuk — Construction Supervision by PT. WECON
Project Details
Semantok Dam in Nganjuk Regency, East Java, is a National Strategic Project (PSN) officially inaugurated by the President of Indonesia in December 2022. Featuring a crest length of 3,100 meters, Semantok holds the record as the longest earthfill dam in Southeast Asia.
PT. WECON was entrusted by the Brantas River Basin Authority (BBWS Brantas) under the Ministry of PUPR as the primary Construction Supervision Consultant to ensure top-tier structural safety and engineering compliance.
Technical Specifications Matrix
| Parameter | Specification Details | |---|---| | Structure Type | Zonal Clay-Core Earthfill Dam | | Crest Length | 3,100 meters (Longest in Southeast Asia) | | Dam Height | 38.5 meters from deep foundation | | Storage Capacity | 32.67 million cubic meters (m³) | | Flood Reduction | Reduces peak Nganjuk flood discharge by 30% | | Irrigation Supply | Serves 1,900 hectares of local farmland | | Raw Water Supply | 312 liters per second for municipal supply | | Client / Authority | Ministry of PUPR — BBWS Brantas |
Key Role & Regulatory Compliance
PT. WECON water engineers performed daily quality control, clay core compaction testing, and piezometer instrumentation monitoring.
The project strictly adhered to Indonesian Dam Construction Permitting Services guidelines and River Diversion Permitting Services for site dewatering operations.
"Semantok Dam is not only a record-breaking engineering milestone, but a vital water security pillar for East Java agricultural prosperity."
Gani Abdurrahman
Director, PT Wecon
