simba - Islais Creek Tranmission Line Failures

These are a few photos taken over the past 3 years
documenting the failures of the the three transmission
lines (or "duct banks") constructed under Islais Creek.
This project was initiated by SF Muni Third Street Light
Rail in collaboration with the SF PUC. Currently, the
transmission lines are flooded, filled with sediment
and contorted by the weight of mud, water and
approximately 400 jet grout insertions meant to
stabilize the pipe. On the contrary, the weight of the
jet grouting has actually caused the tranmissioin lines
to sink, as this area is landfill sitting upon ancient
marsh mud at least 100 to 200 feet in depth. Land
surveyors regulary measure the movement of the
lines, and the latest information from the Port of SF,
as well as SF Muni, is that the area around the
transmission lines will need to re-excavated for
repairs. ( which is at least the third time, not to
mention the stuck drill bore bit on the south side of
Islais Creek)
More information and photos to follow.