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Assalam O Alykum In one of our planned project on which construction not yet started , the problem is that water table is very high that is 2.5m from the average NGL ground level ( +0.2m). The Building is double basement+ ground + seven stories. The client already refuses to go for Tension piles. Therefore, we are going to proceed with the raft foundation. Ground level is +0.7m and the bottom of raft is = 9.60. The total water pressure = 9.6-2.5=7.1x10 = 71 Kn per meter square approximately. I made exercise and it has been found that we cannot stop dewatering unless at least 4 roofs are casted ( upto 2nd floor )to get the factor of safety 1.1 against uplift. ( Concrete volume) On the other hand, client wants to stop dewatering as soon as possible maximum up to ground floor is casted because it has cost 7000 SR per day. What we suggest is after casting the ground floor stop the dewatering but make the holes in the raft foundation at every 2m x 2m grid interval x+y. If in case water table rises The building will sink but not float , but how we can protect the water proofing under the raft. The magna dense aggregate that has the density 40 Kn per meter cube is also not easily available that can increase the dead weight of structure. Can anybody advise