My hometown of Pittsburgh built and xported a floating dam:
http://www.hq.usace.army.mil/cepa/pubs/feb02/story5.htm
Building the new Braddock Dam using "in-the-wet" methods is at the forefront of a Corps initiative to adapt cost-saving techniques to sustain the nation's navigation infrastructure. The Braddock project at Braddock, Penn., is part of the Lower Monongahela River Navigation Project. Replacing the nearly 100-year-old fixed crest dam with a gated dam will let Pittsburgh District replace old, inefficient locks at Charleroi, Penn., and eliminate the 100-year-old Locks and Dam 3 at Elizabeth, Penn.

Traditionally, inland navigation projects are built "in-the-dry" using large temporary cofferdams to provide a dry work area. When construction is complete, the cofferdam is flooded and removed. The "in-the-wet" technique eliminates the time and expense of a cofferdam, and allows building the dam segments off-site while the dam foundation system is built from a floating plant.

River barge info:
http://oldriverbillzumwalt.members.ktis.net/barges.htm
FLOAT'S or Float Barge = The very smallest types, usually less than 20' across and less than 30' long, with about a 2' to 4; drafts, as basic sizes.  Floats are used by small utility boats in all sorts of repair work.  Often found around "Locks & Dams" and some can be self powered by their own small outboard motor, in some cases.   Note ....  Dredges use a number of Floats, to carry their "Discharge Pipe" that trails behind the dredge, used to pump materials out of a channel and off to one side of a river channel in making it deeper.


http://www.key-to-metals.com/PrintArticle.asp?ID=100
Barges. Aluminum barges, carrying various chemical products, have been operated on the American inland waterway system since 1960. A 5200-bbl barge is 97 ft long, 35 ft wide and operates at an 8.5-ft draft. A 9000-bbl barge is 100 ft long, 50 ft wide, and carries 1200 short tons at an 8.5-ft draft. The aluminum barges have 7/16 in. -thick welded 5086-H34 hull plating; the cargo tanks are 5/16-in. 5052-H34 plate. Approximately 120 short tons of aluminum were used in constructing the 100-ft barge, resulting in a weight saving of 150 tons compared to a similar steel barge. This permitted 15% more cargo to be carried, but the corrosion resistance of the aluminum alloys employed in tanks, piping, and hull was the major factor in selection of aluminum for these chemical barges.

Short ton is 2000 lbs:
http://www.onlineconversion.com/faq_09.htm

---------------------------
HEAVY LIFT HELICOPTERS:


http://www.army.mil/fact_files_site/chinook/
CH-47D version, which remains the U.S. Army standard and features composite rotor blades, an improved electrical system, modularized hydraulics, triple cargo hooks, avionics and communication improvements, and more powerful engines that can handle a 19,500 lb load – nearly twice the Chinook’s original lift capacity. An upgrade program exists to remanufacture 300 of the current fleet of 425 CH-47D’s to the CH-47F standard.

Chinook follow-on, the SKYCRANE:
http://www.combatreform.com/nextchinook.htm

per:
AHS International
 217 N. Washington St.
 Alexandria, VA
 22314-2538  (USA)

 Phone: 703-684-6777
 Fax: 703-739-9279
 Email: Staff@vtol.org

CH-53E SUPER STALLION
http://www.sikorsky.com/details/1,,CLI1_DIV69_ETI896,00.html
Basic Mission Payload 36,515 lb

http://www.sikorsky.com/details/1,,CLI1_DIV69_ETI918,00.html
16 ton capacity

http://www.centennialofflight.gov/essay/Rotary/skycranes/HE13.htm

A later version of the S-64 was equipped with two 4,800-shaft-horsepower (3,579-kilowatt) T73-P-700 engines. Civilian versions were built, and a number of ex-military versions were remanufactured for civil use for the Erickson Air Crane Company, which first began operations in 1971. Evergreen Helicopters, Inc. also flies the S-64. Civilian skycranes can lift up to 25,000 pounds (11,340 kilograms).

The skycrane is exactly as its name implies—an aerial crane, nothing more. It has a cockpit pod at the front of a long boom equipped with landing gear mounted on outriggers. This provides a large open area under which the carried load is connected to the fuselage.

Skycranes were used in 1972 when the Chesapeake Bay Bridge connecting Maryland and the Eastern Shore was being built to bring concrete and other supplies to the construction site. In 1993, an Erickson aerial Skycrane, normally used for hauling lumber in Oregon, was used to remove the “Statue of Freedom” from the top of the Capitol dome in Washington, D.C. The statue was placed on the ground while it was being cleaned and restored before being gently returned to the top of the dome, once again with a Skycrane.

S-64:
http://www.fiddlersgreen.net/AC/aircraft/Sikorsky-SkyCrane/info/info.htm
History:
http://www.aviation-history.com/sikorsky/s64.htm