DH: How is the capacity of transit calculated for a project such as this? Are the estimates forward looking enough to address future growth?
GC: Metro is best qualified to answer this. To my understanding Metro has current models that allow estimation of transit trips. However, I think the key element to the tunnel system in conjunction with mass transit is the option that I-45 drivers could have by parking their vehicles at Greenspoint and ride Metro into town (save time, gas, stress, etc). Transit trips can be made move attractive by regulating the cost of toll in the tunnel, cost of parking in downtown, and congestion of traffic at local streets. Take in consideration the inconvenience that has become driving to the Medical Center - many people going to the Medical Center might choose to drive out of their way to access the park and ride facility at Greenspoint
DH: Houstonians are already familiar with the Washburn and Baytown tunnels as examples of past tunnel projects in our area. How does this proposal compare in terms of distance, capacity, and engineering.
GC: Regarding distances: I believe these tunnels were/is shorter than one mile. The Beltway 8 to US-59 is about 14.5 miles.
On the capacity: If not mistaken the purpose of the Washburn and Baytown tunnels were to cross under the bay, probably to avoid building a very high bridge. Also these tunnels served smaller communities and not a city with over two million people. The interesting consideration for building a tunnel across a bay vs. a bridge is the potential for a barge to run into the bridge piers, which has happened several times along the Gulf Coast in the last few years. Also, in case of a hurricane perhaps a tunnel is a safer way to evacuate the coast.
DH: Building a tunnel sounds inherently expensive. How does this project compare to the alternatives utilizing the following metrics: Construction costs, condemnation/annexing of private land, lost productivity relative to congestion, specific requirements/infrastructure to maintain tunnel roadways.
GC: Dr. Sauer, the gentleman from Austria who is an
international expert in tunneling and has been instrumental in helping
me investigate the feasibility of building I-45 in tunnels has put
together a presentation for METRO. In this presentation he outlines the
related costs for building various types of roadways, at-grade, elevated,
depressed and tunnels. The following is the copy of the exhibit that
shows some costs of various types of construction.
However, this does not identify costs related to: construction congestion lost of businesses due to construction, potential to generate revenue via user fees, long term operation and maintenance costs, environmental benefits, quality of life benefits, and more importantly the vision that this type of project could offer Houston in the eyes of the world. One interesting area that should be investigated is the long term cost for operating, maintaining and replacing a traditional highway vs. a roadway tunnels. Another area that MUST be investigated is the health and environmental benefits of tunneling a highway. Some of these analyses are not commonly done. I45 Houston Tunnel continued
