TM 5-818-5/AFM 88-5, Chap 6/NAVFAC P-418
EXAMPLES OF DETAILED DEWATERING SPECIFICATIONS
G-1. General. This appendix provides examples
ample time and knowledge to check the Contractor's
submittals; and a willingness to reject the Contractor's
based on actual specifications for installation of de-
proposals and accept any associated delays in starting
watering or pressure relief systems, extracted from
the project until an acceptable design is submitted.
Government and private industry contract documents.
They have been selected and presented to illustrate the
d. For large and complex dewatering projects where
various types of specifications described in the test
dewatering is critical to the safety of the work, type
B-l specifications are recommended; types A-2 and
B-3 may be suitable if the Owner or Engineer can or
G-2. Types of specifications.
will enforce the provisions relating to approval of de-
a. Type A specifications are projects where the de-
sign, installation, and operation.
watering is not too critical with respect to damage to
G-3. Example of type A-1 specifications
the permanent work or safety to personnel, and only
the desired results are to be specified. This type of
specifications makes the Contractor completely re-
a. General. The Contractor shall provide all de-
sponsible for design, installation, and operation of the
watering necessary to keep the construction and work
areas dry. The Contractor shall design, install, oper-
system(s). Specifications may be brief (type A-1) or
ate, and maintain an adequate system. The system
more detailed (type A-2), depending upon complexity
shall be of sufficient size and capacity to maintain a
and criticality of the dewatering or pressure relief sys-
tem. The examples of these two types are from Corps
dry condition without delays to construction opera-
of Engineers projects.
b. Type B specifications are recommended for large,
b. Submittals. The Contractor shall submit a pro-
complex systems, or where the dewatering or pressure
posed dewatering plan for approval of the Contracting
relief is critical with regard to construction of the proj-
Officer prior to initiation of any construction or exca-
ect, damage to permanent work, and safety.
vation operations. The plan shall show all facilities
(1) Type B-1. A specification that gives a detailed
proposed for complying with this section.
design and requirements for installation of a "mini-
c. Payments. Payment for all work covered in this
mum" system but makes the Contractor responsible
specification will be made at the contract lump sum
price for "dewatering," which price shall constitute
for operating and maintaining the system, supple-
menting it as necessary to obtain the required results.
full compensation for furnishing all plant, equipment,
The installation is then checked with a full-scale
labor, and materials to install, operate, maintain, and
remove the dewatering system.
pumping test to verify its adequacy.
(2) Type B-2. A specification that gives a detailed
G-4. Example of type A-2 specifications
design and installation procedure but makes the Con-
tractor responsible only for normal repairs and opera-
tions. The Government or Owner thus assumes the re-
a. Scope. This section covers the design, furnishing,
sponsibility for the adequacy of the system and its
installation, operation, maintenance, and removal of a
components, major repairs, and replacement of equip-
dewatering system, complete.
ment if necessary.
(3) Type B-3. A specification that is similar to
(1) General. The dewatering system shall be of a
type A, wherein only the desired results are specified,
sufficient size and capacity as required to control
except the degree of difficulty or criticality of the sys-
hydrostatic pressure on all clay strata below elevation
tem requires that the Contractor retain an "Expert" in
- 13.0 feet to depths indicated by the logs of borings,
the field of dewatering or pressure relief systems to de-
to permit dewatering of the area specified in para-
sign, supervise installation, and monitor the system.
graph d below, and to allow all material to be exca-
c. Types A-1 and B-3 specifications should not be
vated, piles driven, and concrete placed, all in a dry
used unless the issuing agency has considerable confi-
condition. The system shall include a deep-well sys-
dence in the (dewatering) qualification of the bidders;
tem, a wellpoint system, other equipment, appurte-