COMMISSION AGENDA – Briefing Item No. 7b Page 3 of 7
Meeting Date: September 11, 2018
airlines arriving at Sea-Tac. More recent design additions included outbound baggage
carousels, conveyor systems, and federal inspection machines to speed the delivery of bags
from the IAF to connecting passengers next aircraft along with life safety refinements to the
design related to fire systems and emergency electrical generators. All scope additions will
allow the completed IAF project to perform better for the airport operators and for passenger
benefit in terms of their processing speed and convenience moving through the airport.
Recent changes have also affected construction cost and schedule. Examples include a robust
long-term baggage system rather than an interim system and an emergency generator scope
addition noted above. That necessary change was made relatively late in design and affected
the ongoing construction work because additional underground vaults and conduit for electrical
power had to be installed that delayed or impacted building foundation work that was already
in progress. In addition contaminated soils were discovered in the areas of foundations and
underground utilities, and as a result delayed foundations and steel framing above. These
construction impacts were compounded by a tight construction site squeezed on three sides by
existing buildings and road and train infrastructure that limited construction access to only one
narrow site road. Another recent but minor example of a change was to add steel framing and
decking for an escalator to complement future customs processing to eliminate waiting delays
for passengers at peak times.
These recent scope additions have been necessary and wise to help make this signature airport
facility efficient for airlines, federal partners, and travelers over its estimated 30-50 year life.
Changes made later in design have a compounding effect upon schedule. As a result necessary
changes have contributed to lengthening the construction portion of the schedule for the main
part of the facility by 8 months from September 2019 to May 2020. Two additional
international capable gates will reach construction completion 6 months later in November
2020. Additional time to complete projects requires additional time from site workers,
equipment, suppliers, office staff, etc. that all drive costs to rise. Added schedule time driven
by subcontractor concerns and contamination found on site and design refinements continued
to drive up costs in the last several months.
The exceptionally busy Seattle construction market has also affected costs. The Seattle market
is the busiest construction area in the US for the last three years as evidenced by leading the
country in the number of construction cranes. This, combined with the security and other
challenges associated with performing construction at an operating international airport, led to
fewer bidders on each particular construction package bid for the project. At times 4 to 6 firms
would show interest in a package, but it was not uncommon to only have 2 bidders, sometimes
only 1. This is because contractors are very busy and other faster time-cycle projects on less
restrictive sites (without security badging requirements, etc.) can be viewed as more attractive.
This is such a competitive market that in the last 4 months, additional cost requests from IAF
subcontractors totaled over $8 million.