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Re: cut and cover-not cheaper, if you have the right conditions to bore.
Author: Al Stangenberger
Date: 01-27-2017 - 10:24
Max Wyss Wrote:
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> A chance with cut and cover, however, is that it
> would be possible to clean up all the utility
> lines, and maybe even bundle them in an additional
> (small diameter) tunnel. Of course, such a project
> would require the cooperation of all involved
> parties.
I'm fairly certain that such a simplification project would have been prohibitively expensive.
Underground utilities on the main street in an old city probably can be simplified (especially San Francisco, which had competing electrical companies' facilities in many downtown streets).
However, it's not cheap -- for example, PG&E's first 110-kv underground circuit (installed about 1949) cost about fifty dollars per foot at that time. Fortunately, it is not on Market Street. Main telephone cables are also quite expensive to replace.
I suspect the cost of replacing the main lines would pale in comparison to replacing the services (electric, gas, water, telephone, and sewer) to every building on Market Street, and doing so with minimal disruption to the customers.
My father supervised PG&E's electrical inspectors on the BART project. He told me that some of their major electrical duct lines were encased and suspended in the excavations for the stations on Market Street since it would have been extremely expensive to relocate them.
Tunneling between the stations saved a lot of trouble relocating utilities. The gains of simplifying the system would not have benefited BART, although they would have had to pay for it.
-------------------------------------------------------
> A chance with cut and cover, however, is that it
> would be possible to clean up all the utility
> lines, and maybe even bundle them in an additional
> (small diameter) tunnel. Of course, such a project
> would require the cooperation of all involved
> parties.
I'm fairly certain that such a simplification project would have been prohibitively expensive.
Underground utilities on the main street in an old city probably can be simplified (especially San Francisco, which had competing electrical companies' facilities in many downtown streets).
However, it's not cheap -- for example, PG&E's first 110-kv underground circuit (installed about 1949) cost about fifty dollars per foot at that time. Fortunately, it is not on Market Street. Main telephone cables are also quite expensive to replace.
I suspect the cost of replacing the main lines would pale in comparison to replacing the services (electric, gas, water, telephone, and sewer) to every building on Market Street, and doing so with minimal disruption to the customers.
My father supervised PG&E's electrical inspectors on the BART project. He told me that some of their major electrical duct lines were encased and suspended in the excavations for the stations on Market Street since it would have been extremely expensive to relocate them.
Tunneling between the stations saved a lot of trouble relocating utilities. The gains of simplifying the system would not have benefited BART, although they would have had to pay for it.
