When there is confined water at the bottom of foundation pit in the basement excavation and foundation construction process, if the design is inconsiderate or the construction operation are improper, piping will occur caused by drilling through confined aquifer. According to the engineering case of a foundation pit piping treatment in Ningbo, steel casing, high pressure jet grouting pile and double fluid grouting comprehensive processing technology are presented in this paper, the above technologies can effectively deal with the similar accidents.