You may have noticed that we haven't broken ground yet on the additions to the Middle School. This delay is due to some unexpected results from the soil tests, particularly what was found when they drilled down 50 feet beneath the lower parking lot, where the two-story addition would be.
After further testing and analysis of the samples, our lead architect Max Grebe told me the results were, “Worse than the worst case scenario they could imagine.”
The soil testing showed that the area north of the 1993 wing is basically “quicksand”. In the geo-tech’s assessment, if there were a seismic event the two-story addition we planned for the south side of the existing building would sink by as much as 18 inches, whereas the existing wing may sink by 6 inches. This differential settling would likely cause the entire structure to collapse.
The new wing could be stabilized by adding 100-200 vibratory stone columns to support the new structure and reinforcing the existing hillside. This would add at least $1,000,000.00 to the construction costs and create construction delays as well.
It was determined that the best course of action may be to abandon our current plans and redesign an entirely new building to be located on the east side of our property where the soils are better. Both Swank and LPW committed to accomplishing this without additional cost to the District.
The necessity to re-design the building may delay the start of construction until next spring. The completion date for the project would still be August, 2020. On the positive side, constructing a new building on the other end of the property should mean less disruption for teachers and students during the process.
The architects will incorporate the work we have already done with regard to the design and layout of the music room, science lab, etc...
One question that comes up as a result of this information is whether the current building is safe. The 1993 addition to the middle school was built to code at the time. The type of "seismic event" that could cause differential settling would be an earthquake of at least 6.0 magnitude, occurring within 10 kilometers of the school. This would be a once in 500 years event.