Emergency Survey Of 85 Miles of Delta Ship Channels

The New Year’s Flood of 1998 caused shoaling throughout the 44-mile long Sacramento Deep Water Ship Channel and the 41-mile long San Joaquin River Ship Channel. Sea Surveyor deployed multiple survey vessels to conduct emergency hydrographic surveys of 85-miles of Ship Channels under contract to the Sacramento District, Corps of engineers.

Sea Surveyor conducted multiple Class 1 hydrographic surveys on the Sacramento and San Joaquin Deep Water Ship Channels during “flood” conditions. Tides were monitored at 1-mile intervals upstream and downstream of the survey vessels using self-recording tide gauges referenced to local benchmarks. Soundings were collected across the Ship Channels along survey lines spaced at 100’ intervals and along the channel centerline.

Sounding charts and cross-sectional profiles of the Ship Channels were delivered to Corps representatives within 24-hours of completing the field survey. Dredge volumes for shoaling areas were computed.

Sea Surveyor continued to provide Pre- and Post-Dredge Surveys and Sediment Testing to the Corps of Engineers until dredging of all shoal areas was completed in 2000.

SERVICES INCLUDED:

 Class 1 Condition Hydrographic Surveys.
 Sediment Sampling for Biological/Chemical Testing and Analyses.
 Class 1 Pre-Dredge Hydrographic Surveys.
 Dredger Inspection.
 Class 1 Post-Dredge Hydrographic Surveys.
 Plotting of Sounding Charts and Cross-Sectional Profiles.
 Dredge Volume Computations.