Pipe Inspection / River Crossing


County of San Luis Obispo, California

Ballard Marine Construction was contracted to develop an underwater survey approach to identify anomalies on the interior of the 30” diameter pipeline that crosses beneath the Nacimiento River.  The situation was the pipeline was leaking water at a non-specific location 95ft (29m) below the surface.

After an entry point was excavated confined space commercial divers traveled into the pipe over 400ft (122m) utilizing specialized tooling, lighting and HD cameras.  Initial measurement were taken at a variety of locations in addition to looking for obvious internal deformities.  Due to the locations of the anomalies within the pipeline, ACFM technology (ACFM is an electromagnetic inspection technique that introduces an alternating current into the surface of the component to detect surface-breaking cracks.) was utilized instead of the conventional MPI or Eddy testing.

Specialized equipment and ingress / egress measures were required to access anomalies located 1,000ft (304m) from the point of entry.   Work was conducted in situ in over 105ft (32m) of water at high altitude.