Abstract: A basement of a highrise building experienced float up damage during the construction. This paper analyzes possibly factors that leading to the accident. The paper presents the importance of estimating the groundwater level during the construction as well as the applying the proper basement construction methods. Factors, such as, seasonal precipitation, topography and environment adjacent to the basement, that affecting the groundwater proof and drainage design are discussed. Understanding geotechnical and hydrological conditions during the design and construction is critical.

Key words: Basements, Float up Accidents, Groundwater Proof and Drainage, Sink Effect