“The Lake Merritt Boat House is located on Lake Merritt (a large body of inland salt water) within the city of Oakland, CA. It was built in 1909 as part of a movement to enhance the City of Oakland. The building is U-shaped and has two stories, each of approximately 8500 square feet (790 square meters). Voters approved a plan in 2002 to return the dormant historic boat house to near its original design. The new design required installation of micropiles for seismic upgrade of the building. The general contractor installed a coffer dam, dewatered the area, and began excavation to expose the foundation to complete this work. Once exposed, it became evident the building’s substructure had many problems. Cracking, spalls, and signs of corrosion were observed throughout.
Severe spalling and structural deficiencies were uncovered once excavation began and the substructure was exposed in December 2006. Thorough investigations were immediately employed to determine the extent and causes of the deficiencies. Plans and specifications were developed by February 2007. The project was bid in March and awarded to an experienced concrete repair specialist contractor in April. The repair contractor mobilized in April, started excavating in May, and completed the repairs in September 2007. A challenging job was completed in very tight working conditions. The project was completed on time, within budget, and without any injuries to the work crew.”