A building was razed southwest of the intersection of Leavenworth Street and 14th Street for the construction of a new apartment building. Removal of the structure exposed the east exterior basement level wall of the Leavenworth Lofts, a five-story (plus basement) office/warehouse building constructed in 1915 and recently renovated to living space. The two structures were built right up to the common property line such that the exterior walls were in contact. After removal of most of the foundation wall of the other building, a one and one-half inch wide separation was observed in the brick wall of the Lofts over a length of 60 feet. Any additional length of crack extending to the north of that exposed was covered by foundation wall remnants on the exterior and plywood panels and electric meters on the interior. Based on the cracking pattern, it was estimated that approximately 80 feet of a middle section of the wall had settled. The crack extended completely through the two-foot two-inch wide multi-wythe brick wall. The settled section of the basement wall of the Lofts needed to be stabilized before the last section of foundation wall remnants could be removed and construction could begin on the new apartment building. The closest test boring completed for the new apartment building encountered fill soils to a depth of 13 feet, soft to stiff lean clay and loose sand to a depth of 38 feet, and stiff to hard sandy lean clay (glacial till) to the bottom of the boring at 65.5 feet.
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