EP 1110-1-8
(Vol. 1)
31 July 03
AVAILABLE TIME TO DREDGE BY REGION
(In Months)
Type of Dredging Operation
Region
Pipeline
Bucket
Hopper
Atlantic Coast and tributaries
9
10
10
Gulf Coast, Lower Mississippi and
10
10
11
Tributaries
Great Lakes, Upper Mississippi and
8
8
8
Tributaries
West Coast and Tributaries
9
9
9
Figure 4-1. Months Available by Region
SECTION III. LIFE
4.4
Life
The life for determining ownership and operating costs is defined as follows:
a. The Useful Life is expressed in years in table 4-1. It is the economic life of
the equipment and is used to develop ownership rates for various types of dredging
plant.
b. The Physical Life is expressed in hours (hrs) in table 4-1. It is the life of the
unit based on effective working time and is used to develop operating rates for various
types of dredging plant.
4.5
Annual Hours Available
The annual hours available to dredge can be established for each type of plant
based on the months available and the estimated effective monthly hours worked.
Dredging time is defined as effective plus noneffective working time. "Effective working
time" is defined as time during the dredging operation when actual production is taking
place. "Noneffective working time" is defined as time during the dredging operation
when the dredge is operational but no production is taking place. For complete
definition of terms see ER 1110-2-1302, Engineering and Design, Civil Works Cost
Engineering. The total annual hours available can be expressed by formula, as follows:
4-2