The Kochi Naval Base in Kerala has two jetties, i.e., the North and South jetty. The existing North Jetty was small to cater to the increased requirement of berth space. A modern jetty meeting the requirements is constructed after demolishing the existing North Jetty. This article presents the study of the performance of 27.5 m deep prefabricated vertical drains (PVDs) to accelerate the consolidation of very soft clay with a non-homogenous soil profile present below the jetty. The total area for improvement was 23,664 Sq.m and maximum depth of improvement was 27.5 m below the working platform. The working platform level is»1.5 m above the existing ground level. The soft clay has the parameters; average value tip resistance (qc) = 0.6 MPa, average coefficient of vertical consolidation (Cv) = 0.7m2/yr, average coefficient of horizontal consolidation (Ch) = 4.0 m2/yr, and coefficient of primary consolidation (Cc/1 + eo) = 0.20. The clay was low to medium sensitive with a sensitivity value of 2.0. To accelerate consolidation settlement, PVDs were installed 27.5 m deep, where the maximum expected total consolidation settlement after the preloading period is»1.4 m, and the residual settlement after 50 years is less than 10 cm. To ensure the stability of the surcharge during pre-loading, the surcharge was placed in two stages, stage I consisted of a 3 m surcharge with a waiting period of 2.5 months to achieve 65% degree of consolidation and stage II up to the required level to achieve 95% consolidation with consolidation period of 7.0 months with total pre-loading period of \(\approx 9.5 \)  months. The settlement and water levels were monitored to ensure the performance of ground improvement work. 33 surface settlement plates and four piezometers were used in the monitoring campaign. Ten CPTs and an additional three oedometer tests will be carried out after surcharge removal to measure the soil parameters after improvement. This paper shows that PVDs can be effectively installed down to 27.5 m under the ground in the case of soft clay with a non-homogeneous soil profile.