The Lagoons project, which is now part of the larger Mohammed bin Rashid City development, was previously being developed by Dubai Holding subsidiary Sama Dubai. Its work on the project stalled in early 2009 before building started and as Dubais property market slumped.
Emaar has already started some early works on the site and has tendered several buildings including six residential towers, 29 villas and three hotels.
Emaar and Dubai Holding have considered working together before. In 2009, the two companies were in advanced negotiations to consolidate their real estate businesses, forming a new company with total assets of AED194bn ($53bn), including the Lagoons. The proposed merger never happened.