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The San Francisco Airport Expansion Proposal

It is generally accepted that San Francisco's airport needs new runway improvements that will permit simultaneous landings and takeoffs in most weather conditions. It is also conceded that these improvements will require further encroachments on San Francisco Bay. The San Francisco International Airport (SFIA) has conducted extensive studies of a number of runway configurations that will satisfy their operational requirements.

Many environmental groups in the region are united in their opposition to runway expansion in general, and are adamently opposed to plans that are based on dredging and fill. Float Incorporated provided SFIA with a conceptual proposal for floating the expanded runway system on PSPs. SFIA received Float's proposal through one of their consultants on December l, 1999. A PDF file of this concept is available by clicking on SFIAProposal.pdf .

Two design concepts were submitted. The first is for runways with a constant elevation, i.e. they do not rise and fall with the tidal action. The second is the classic floating design, which is less complicated and, therefore, more practical. Furthermore, its estimated cost is approximately half that of the constant level design.

On January 11, 2000, the SFIA Airfield Development Bureau issued a Request for Qualifications (RFQ) for Offshore Runway Construction Concepts. They stated that this was intended to provide an open process by which they could receive innovative runway concepts. Interested parties were urged to team together to provide the broad range of expertise and experience required in runway construction. Submissions were due January 31 following which selected (judged to be qualified) teams would be invited to respond to a Request for Proposals (RFP), due to be released about February 9. From the RFP responses, including an oral presentation to a hand picked board of experts, SFIA intended to select three or four teams to further develop their concepts. Each team would be provided $250,000 and asked to complete their study in three months.

Float replyed to this RFQ, and was judged to be qualified, with a team consisting of Weidlinger Assoc. - structural engineering, Pre Con Inc., a subsidiary of Blue Circle Industries PLC - concrete forming, Ferma Corporation - general engineering, ECM Assoc. - construction cost estimating, and Olivia Chen Consultants - environmental issues.

In February, 2000, Float submitted its proposal to SFIA and presented it to the Blue Ribbon Panel of Experts in early March. It was clear from the first questions about whether a PSP had ever been built that there was an absolute unwillingness to consider it on merit, and, indeed, Float was not even awarded a contract to develop the concept. What was interesting was the complete lack of any constructive criticism or credible reason why it was not feasible beyond the normal fear of being first. Float urgently requested they consider the unfortunate consequences the Japanese had suffered from making the same judgement. Japan had considered floating Kansai airport in Osaka, and had elected to go with landfill, stating that they knew landfill, but they did not know floating. For those unaware, Kansai has subsided over 35 feet, is still at the rate of about a foot a year, and has gone in excess of $13 billion over budget. Their beautiful terminal is on jacks that are adjusted daily to relieve the stress on the structure.

Environment
· A floating runway will be immune to damage by earthquakes in this earthquake prevalent region. San Francisco Airport is situated between faults on the East and West side of the Bay.
· Although a floating structure casts a shadow on the bottom, which may be harmful to some species, it may be a benefit to others. The same may be said for runways on a bridge structure supported on closely spaced columns. On the other hand, silting, during and following the fill process, can cause widespread environmental damage.
· Current patterns will likely be adversely affected by fill and closely spaced columns, but only insignificantly affected by floating structures.

Risks
The risks associated with a structure floating on the surface of water are less than the risks for one supported on the bottom. The physics of flotation are well known and totally predictable while the reaction of the bay floor to high loads varies from place to place and predictive data is subject to interpretation. The continued settling of the fill under Osaka Bay's Kansai Airport is a case in point. A bottom mounted bridge structure would entail the same concerns.

Costs
The costs of Float Inc.'s proposals are conservatively estimated and are likely to be substantially less than other proposed solutions. Also the time of construction and installation are estimated to be roughly half that for either fill or a bridge structure.