case study presentation- bostons big dig
DESCRIPTION
Case Study PresentationTRANSCRIPT
CASE STUDYBOSTON’S BIG DIG
Ajay Gupta
Engineering Cost Estimation Techniques.
EMGT - 709
Big Dig: Project Summary
Demolition of Existing Central Artery and Replace it with 3.5 Mile underground tunnel.
Ted Williams Tunnel: Connects I-90, I-93, and Logan International Airport.
Leonard P. Zakim Bunker Hill Bridge: I-93 Bridge over the Charles River.
Rose Kennedy Greenway in the space vacated by the previous I-93 elevated roadway.
BEFORE
AFTER
Central Artery Before and after
Before: 2003 After: 2005
Why Big Dig ?
1959 Early 1990
Funding Sources
Big Dig…
InterstateHighwayProgram
IntermodalSurface
TransportationEfficiency Act (ISTEA)
National EconomicCrossroads
TransportationEfficiency
Act (NEXTEA)
TransportationEfficiency
Act (TEA) - 21
Mass.Highway Dept.
formerly (Mass. Dept. of
Public Works)
Mass. Transportation
Authority
Mass. Turnpike Authority
Mass. Port
Authority
State Bonds(Issuing authorityunknown)
Federal
State
Original Cost Estimate: 1982 Dollars
Estimated cost $2.5 Billion
Project Features:
New Charles River Crossing
Joint Venture Contract
Right of Way/ S. Boston
Extend I-93 South
Tunnel Covers
Utilities Relocation
Workmen’s Compensation
Other
Source: Final Environmental Impact Statement,1985
Completion Date: 1998Completed - 2007
Actual Cost $8.08 BillionActual Cost $14.6 Billion
In 2003 Dollars
Cost Estimation Revision 1
Revise Cost Estimates in 1992 Dollars
• Original Estimate $2,564
• Features Added $471
– I-90 and I-93 HOV Lanes
– South Boston Haul Road
– Material disposal/ hazardous materials
– Deleted interchange
– Other
• Scope change to existing project features $2,151
Total In million Dollars $5,186
Escalation to 1992 Dollars: $2,553
Subtotal $7,739
Cost History in Million Dollars
1985
EIS
1987
ICE
1989
ICE
1991
ICE
1991
APF
1992
APF
1992
APF
w/ N
CRC
1994
CSU
6 w/ I
nflat
ion
1994
CSU
6 19
97 R
ebas
elin
e
2000
CSU
7
2001
CSU
8
2002
CSU
8
2002
CSU
90
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
2,5643,175
4,4365,193
5,7806,443
7,740
10,468 10,841
14,07514,475 14,625 14,625
2,5643,175 3,409 3,708 3,963 4,317
5,1875,597 5,810
7,658 7,886 7,972 8,000
Chart Title
2003 Dollars 1982 Dollars
Source: Completing the “Big Dig”: Managing the Final Stages of Boston’s Central Artery/Tunnel Project (2003).
Project Escalation: 7 years behind schedule
1989 PMS REV. 1
1990 PMS REV. 2
1991 PMS REV. 3
1992 PMS REV. 4
1993 PMS REV. 5
1994 PMS REV. 6
2000 PMS REV. 7
2001 PMS REV. 8
2002 PMS REV. 9
1994 1996 1998 2000 2002 2004 2006
1998
1998
1998
2001
2004
2004
2004
2004
2005
Source: Completing the “Big Dig”: Managing the Final Stages of Boston’s Central Artery/Tunnel Project (2003).
Reasons For the Cost Growth
15%
8%
7%
5%
3%2%
5%
55%
Mitigation
Scope Growth
Accounting Changes
Traffic
Schedule Maintenance
Contigency for Unknowns
Other
Inflation
Source: Completing the “Big Dig”: Managing the Final Stages of Boston’s Central Artery/Tunnel Project (2003).
Mitigations
Opportunity to turn complaint into benefits
Rats
Fish
Fire Boats
Memorials
Parks
Final mitigation costs $3 Billion.
Final number.
$22 billion and wont be paid until 2038.
Including interest on debt.
Interim borrowing.
Principal repayment.
Possible future growth of the bottom line for construction and support contracts.
Commonwealth’s taxpayers and toll payers will foot a bill for the remaining $9 billion over the life of the bonds. This sum is equivalent to $1,500 for each of the Commonwealth’s six million citizens.”
Conclusion
The original estimate was developed in 1982 dollars, without allowance for inflation or mitigation.
Mitigation costs are expected to be very high. Requirements for significant mitigation were identified in the original 1985 cost estimates, but the costs were not identified.
Other factors that increase costs and delay schedules should and could have been anticipated and addressed through additional planning and design, site analysis, and cost and schedule contingencies.
Other Projects could benefit from the lesson learnt from Big Dig.
THANK YOU !