February 2008  |  Volume 78, Number 2

Crossing the Narrows

The design of the new Tacoma Narrows Bridge, in Washington State, benefits not only from the knowledge that has been gained about the aerodynamics of suspension bridges in the years since the first suspension bridge across the narrows collapsed—in 1940 just four months after its opening—but also from the design/build delivery method, which enabled the design team to incorporate innovations in an efficient and cost-effective manner that might not have been possible otherwise.

Modular Mooring

By Markus Wernli, Ph.D., P.E., and Preston S. Springston

To reduce the costs associated with waterfront construction and maintenance, the U.S. Navy has developed an alternative pier—the modular hybrid pier (MHP)—that features a double-deck floating concrete structure. The MHP consists of a series of uniform modules constructed of advanced materials and developed in accordance with the principles of sustainable design.

Capitol Achievement

By Jeff L. Brown

Updating Virginia’s capitol building to meet the needs of a 21st-century government while preserving the historic structure for future generations required a delicate balancing act. The project succeeded not only in renovating and restoring Thomas Jefferson’s original building but also in adding a spacious underground visitors’ center.

Small Footprint, Big Promise

By Thomas E. Vik, P.E., BCEE, and Mark Surwillo

Faced with population growth, increasingly large wet-weather flows, and stricter permit limits on ammonia nitrogen, a Wisconsin wastewater treatment facility adopted ballasted sedimentation for primary treatment and peak flows followed by biological aerated filtration for secondary treatment. Believed to be the first of its kind in the United States, this high-rate configuration requires a fraction of the space that would have been taken up by conventional treatment systems and is expected to handily meet all permit requirements.