FACT: The Burnside Bridge is 92 years old and would suffer extensive damage in a Cascadia Subduction Zone earthquake. Multnomah County will decided by fall 2018 whether to fully replace the bridge or undergo an enhanced seismic retrofit.

The bridge is also currently undergoing a maintenance project that is estimated to cost $20 million.

Suppose the county expects to incur the following cost for each option:

Full replacement

Direct labor $150M

Direct materials $300M

Overhead (includng $80M in design cost) $115M

Enhanced Retrofit

Direct labor $115M

Direct materials $200M

Overhead (including $60M in design costs) $100M

QUESTION: What is the total relevant cost of each project? Given this limited data, which project would you recommend that the county pursue? What qualitative factors influenced your recommendation?