Alaro City is a 1,000-hectare development within the Lekki Free Zone which aims to be the largest and most economically sustainable city within Lagos. Arup designed the infrastructure masterplan, and the engineering designs for the infrastructure works including drainage, utilities, paving and roads.

The city is modelled into two major zones, the industrial zone, and the commercial and residential zone, created so future communities can work, live and play all within the development. The infrastructure is designed to enhance the liveability of the city by reducing flood risk and the heat island effect through the creation of green spaces.

Following the site’s terrain and its natural topography, the masterplan by Skidmore, Owings and Merrill in collaboration with CityScape Planner based in Lagos, was designed to accommodate a major drainage system in response to Lagos’ vulnerability to flooding. This was developed into green-ways and retention ponds by Arup to serve as a natural water harvesting process, as well as the major site drainage discharge points designed to control flooding. This sustainable urban drainage system will create green corridors throughout the site and provide recreation space for residents.

A sustainable urban drainage system was also designed for the roads’ main drainage channels. Natural trapezoidal green bio swales and rain gardens were incorporated alongside trees and green landscaping adjacent to the roads and pavements. This green infrastructure will absorb water and are cost-effective compared to typical reinforced concrete channels. For the paving we advised the use of lighter-coloured permeable pavement to reduce the amount of radiation absorbed and to enable rainwater to seep through its porous surface reducing surface stormwater runoff.

Partners & collaborators

Skidmore, Owings and Merrill / CityScape Planner