[3] The project will also involve the reclamation of 700 hectares (1,700 acres) west of and abutting the expressway dike, separated from the shoreline by a 100-to-150-meter (330 to 490 ft) channel in Taguig and Muntinlupa.
[5] When constructed, it is expected to ease traffic congestion along the Muntinlupa and Calamba areas and to serve as a flood control measure for communities on the western shore of Laguna de Bay.
[13] The project most directly intended to prevent the water volume displaced by the expressway dike from causing larger-scale flooding on the lake's eastern shore is the construction of a 20-kilometer (12 mi) "Pacific spillway."
Earlier attempts to construct a large dam in Tanay's Barangay Laiban have raised concerns among various stakeholders because of its potential environmental impact[10] and because it would affect the ancestral lands of the Remontado Dumagat people.
[21] In the aftermath of the floods brought about by Typhoon Trami (Maring)[22] in August 2013, President Benigno Aquino III made plans for the dike project public.
[23][24] Media outlets referred to the proposal as a "megadike,"[24][25] but Public Works Secretary Rogelio Singson corrected this, saying it would be called a "road-ring dike.
[28] The DPWH later announced[29] that it would make the "necessary clarification" regarding the project's environmental impact, specifying that concerns raised in the meeting had included "the height of the dike, the construction of water circulation, the separation between the low-lying communities and the new islands that would be created as part of the reclamation, the establishment of pumping stations, among others.
[34] On July 28, 2014, President Aquino cited the expressway dike in his 5th State of the Nation Address as one of the infrastructure projects approved by his administration as part of its disaster preparedness efforts.
[35] Cosette Canilao, Public-Private Partnership (PPP) Center executive director, identified the 14 companies that bought bid documents as of August 18, 2014:[36]