Case Studies: Monitoring Pipeline Dredges

Technical Note DOER-I1

July 1999 (Revised April 2000)

Case Studies:

Monitoring Pipeline Dredges

PURPOSE: The technical note (TN) herein documents current Corps of Engineers' experiences

with monitoring contractor pipeline dredges. A series of subsequent TNs will describe the

development and operation of the Pipeline Dredge Silent Inspector (SI).

BACKGROUND: Since Congress passed the Rivers and Harbors Act of 1824, the U.S. Army

Corps of Engineers has been responsible for keeping authorized waterways navigable. The manner

in which the Corps has fulfilled this mission has changed significantly over this time span, especially

since 1976 as the reduction of the Government-owned hydraulic dredge fleet has modified the Corps'

role from dredge owner/operator to that of contract inspector and administrator. Until recently, the Corps

depended almost completely on Federal inspectors, placed on contractors' hydraulic pipeline dredges,

to provide quality assurance of contracted dredging. While this method of overseeing contract perform-

ance worked well in years past, and still does within some Districts today, there are certain Districts that

currently cannot perform the level of contract oversight they desire. Dredging inspector rosters have been

cut by manpower reductions, or the number of dredging contracts has increased without a corresponding

increase in the number of inspectors. In some cases, the Districts have to rely solely on the contractor

documentation of dredging activities or contract inspectors, rather than on independently recorded

information to determine the validity of contractor claims.

These factors, along with the increasing availability of electronic sensors and low-cost computing

capability, have led to the development of various automated systems to record dredging and

disposal activities for both Government-owned and contract dredges. The Corps Districts men-

tioned in this TN have specified documentation of hydraulic pipeline dredge operating parameters.

However, differences from District to District between respective data-collection efforts do not

allow the Corps, as a whole, to realize the maximum benefits of an automated approach. For

instance, for the larger dredging contractors that may work for several Districts, any monitoring

disparity means increased costs to meet or change the monitoring requirements.

The SI work unit of the Dredging Operations Environmental Research (DOER) Program was

established to develop standardized, automated monitoring systems for dredging activities Corps-

wide. A previous work effort developed specifications and analysis software for a hopper-dredge

monitoring system. The monitoring systems will provide information that assists Corps personnel

in planning, estimating, contract quality assurance, and settling contract disputes.

INTRODUCTION: The SI work unit is defining standards and procedures and developing

technology for automated monitoring of contract dredging. The resulting SI system will provide the

means (standards and software implementations of those standards) to use these acquired data to

assist the Corps in performing its dredging mission. The SI work unit is following a process of first

defining requirements (needs) and then designing and implementing technology to meet those

requirements.