How LiDAR is Preventing the Next Big Infrastructure Collapse -- The Collapse of the Cabagan–Santa Maria Bridge in Isabela
- Clinton Bravo
- Mar 19
- 3 min read
The collapse of the Cabagan–Santa Maria Bridge in Isabela on February 27, 2025, has raised significant concerns regarding infrastructure safety and the factors leading to such failures.
Bridge Overview
Structure: The Cabagan–Santa Maria Bridge was a 990-meter-long tied-arch bridge connecting the municipalities of Cabagan and Santa Maria in Isabela, Philippines. It featured twelve arch spans measuring 60 meters each and nine pre-stressed concrete girder spans.
Completion: Construction began in November 2014 and was completed on February 1, 2025, at a cost of approximately ₱1.2 billion.
Incident Details
Collapse: On February 27, 2025, the third span from the Cabagan side collapsed after a 102-ton truck attempted to cross it, resulting in injuries to six individuals.
Potential Causes Under Investigation
1. Overloading:
The Department of Public Works and Highways (DPWH) indicated that the bridge had been "overstressed" due to the passage of a convoy of heavy trucks, suggesting overloading as a primary factor in the collapse.
2. Design Considerations:
DPWH Secretary Manuel Bonoan noted the bridge's unique design, which used solid steel beams instead of cable strands, prompting an investigation into whether design aspects contributed to the collapse.
Engineer Albert Cañete, responsible for the bridge's design, refuted claims of a design flaw, asserting that the structure adhered to the Bridge Code of the Philippines.
Understanding the Cabagan–Santa Maria Bridge Collapse
The Cabagan–Santa Maria Bridge was a 990-meter-long structure, featuring twelve arch spans and nine pre-stressed concrete girder spans. Built at a cost of ₱1.2 billion, it was a crucial connection between Cabagan and Santa Maria, Isabela. After nearly a decade in development, it was officially completed on February 1, 2025.
However, less than a month later, the third span of the bridge collapsed after a 102-ton truck attempted to cross it. This raised serious concerns regarding the bridge's load capacity, design integrity, and maintenance strategies.
This incident serves as a powerful reminder that every meter matters in engineering. Even minor surveying errors or overlooked structural weaknesses can lead to massive consequences.
How ABSD LiDAR Surveying Can Help Prevent Bridge Collapses
1. Structural Integrity Monitoring – LiDAR can detect small cracks, shifts, and structural weaknesses before they become hazardous. Aerial and ground-based LiDAR regularly scans bridges, tracking changes over time and alerting engineers to potential risks.
2. Flood and Erosion Risk Mapping – Bridge collapses can be influenced by erosion or foundation instability. LiDAR can scan riverbeds and soil conditions, predicting where erosion could weaken a bridge’s foundation and allowing preemptive reinforcements.
3. Faster and Safer Inspections – Traditional inspections, especially for regular monitoring purposes, require road closures and manual assessments, increasing costs and risks for engineers. LiDAR allows for rapid, remote bridge assessments, reducing downtime and improving safety.
For example, ABSD did a Bridge, which is one of the longest bridges in the Philippines, connecting Samar and Leyte, utilizing LiDAR Surveying technology to identify potential repair requirements and assess its current structural condition for further improvements. This initiative aims to maintain the bridge’s structural integrity.
In this project, we precisely detect every crucial component of the bridge, from the steel framework to the smallest details such as bolts. This level of accuracy is crucial for ensuring the safety and longevity of this iconic structure.
With LiDAR, inspections and regular structural monitoring, failures like this can be avoided. Governments, engineers, and developers must embrace LiDAR Surveying technology to ensure safer, more resilient infrastructure.
At AB Surveying & Development (ABSD), we are committed to providing accurate and reliable as-built surveys or maps by using survey-grade LiDAR to prevent costly and dangerous infrastructure failures. For bridges and other structures, we offer aerial and terrestrial LiDAR surveys that provide essential data needed to ensure bridges, roads, and other infrastructure projects are built and maintained to the highest safety standards.
Why Choose ABSD?
✔ Industry-Leading LiDAR Surveying Services – We use the latest survey-grade LiDAR systems that provide millimeter-accurate 3D models.
✔ Accurate Mapping – We provide reliable, precise, and accurate maps that are needed to ensure projects are maintained to safety standards.
✔ Faster, Safer, and Greener Survey Solutions – LiDAR surveys are faster than traditional inspections, saving time, money, lives and are environmentally friendly.
Don’t wait for the next collapse.
Ensure your infrastructure is built to last with ABSD’s high-precision LiDAR surveying.
📩 Get a consultation today: https://www.absurveyingph.net/get-a-quick-quotation
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