By 2050 the sea level will rise with 3 metres. For this project, we from Deltaworkers have looked at solutions to defend Mumbai against this sea level rise with international proffesionalls from India. With these professionals we came to the conclusion that a dike to protect the peninsula would be the best solution. The focus for this project is on the sea part of that dike. For the research of the dike we have looked at existing sea dikes and dams to conclude what would be the best solution for a dikeprofile. There has also been taken into account that the dike has to be environmentally and economically adaptable. Next to this dike there has also been looked into a sluice to keep the Mumbai Harbour intact. With all of the above mentioned point taken into mind, we from Deltaworkers think we put up a very good way to keep Mumbai safe from 3 metres of sea level rise.