Construction of Stabilization Works
approach is that legal and administrative constraints on determining and assessing the penalty
for exceeding the time allowed for completion may prevent the penalty from being high
enough to result in any significant acceleration of the contractor's operations.
10.2.2 RESTRICTIONS IMPOSED BY RIVER CONDITIONS
A generally accepted axiom of construction contracting is that only the end product
should be specified, leaving operational procedures to the contractor. However, some river
stabilization projects involve an exception, where it is advisable to impose operational
restrictions on a contractor if river stages are temporarily too high for effective work. This
may be necessary to insure that the contractor does not attempt work such as bank grading,
placement of filter material, and placement of subaqueous stone when depth of water or flow
velocity are too great for satisfactory results to be ensured. Since it is often impossible to
precisely verify the in-place condition of subaqueous work, specifying the conditions under
which the work must be done reduces the risk of an inadequate job.
The simplest way to impose such restrictions is to include information on river stages
in the advertisement, and to specify any restrictions that will be imposed on the contractor's
operation when river stage exceeds a given value. Information on river stages is usually
provided to prospective bidders in the form of historical records at the nearest gaging station,
accompanied by a caveat that historical stages do not necessarily represent the extremes
which may be experienced during the course of the contract.
An alternative to that approach is to define restrictions on operations in terms of depth
of water or current velocity at the jobsite. The risk in this approach is that it involves some
conjecture even by the designer, and that bidders unfamiliar with site conditions will certainly
not be able to precisely define the impact of such restrictions on their operation. Therefore,
bidders may not have a common basis for preparing bids.
A third alternative presents the most flexible approach from an engineering standpoint,
but is potentially the most troublesome from an administrative perspective. That is to state
that operations will be temporarily suspended when, in the judgement of the contract
administrator, river conditions preclude satisfactory execution of the work. If it becomes
necessary to actually impose these undefined restrictions, claims by the contractor for
additional payment may ensue, but that will likely be preferable to the alternative of
continuing work under unsatisfactory conditions.
A related but separate issue concerns damage to partially completed work as a result
of the river's flow. Specifications for river stabilization work sometimes include a definition
of the responsibilities of both parties if "unusual" flows or "floods" damage the work in
progress, but interpretation of these clauses often involves legal disagreements when such an
event occurs, or is alleged by the contractor to have occurred. Contract clauses defining
"changes in site conditions" versus "conditions that would have reasonably been anticipated,"