Construction of Kenya's first eco-city - a residential settlement that is environmentally, socially, economically and culturally self-sustaining - has commenced on the outskirts of Mombasa, with the first phase expected to be ready for occupation by the third quarter of this year.

The whole project will take four to five years to complete.

Going by the name Hacienda, the development, located in the Mwakirunge area of the North Coast, off the Mombas-Malindi highway, will have 6,250 housing units - of two- and three-bedroom flats, and three- and four bedroom bungalows - to be developed in 10 phases.

The plan also includes a hospital, school, playgrounds and recreation facilities, a police station, commercial centres and office blocks, among other vital amenities.

According to Urban Ecology Australia, a non-profit organisation promoting people- and nature-friendly urban settlements, an eco-city is a human settlement that enables its residents to live a quality life while using minimal natural resources.

David Muniu, a director at Hacienda Development Holdings said, "Hacienda has been designed to improve the image and function of Mombasa as a vibrant, modern and environmentally sustainable city in Africa."

Hacienda Development Holdings, the developers of Hacienda say the design of the buildings will make best use of the sun, wind and rainfall to supply the energy and water needs of the residents.

The project's design include the development of wetlands to harvest, biologically treat, and recycle runoff water for household use, a solar/wind power station, and the planting of 10,000 trees.

So far, the developers say they have signed an agreement with the African Conservation Trust for the establishment of a tree nursery on Hacienda's Mwakirunge project.

Trees and shrubs from the nursery will be planted throughout the development to improve the soil quality, prevent erosion and enhance the overall beauty of the estate. The long-term goal of the tree planting is to contribute to Kenya's re-afforestation programme.

Except for the first phase that will use electricity, the entire complex will use solar power and wind, thus conserving the environment.

The company picked the name Hacienda because of the development's "expansive nature, being built on 500 acres of land and expected to host over 6,000 families." Hacienda is a large homestead on a ranch or estate usually in places where Spanish culture has had an architectural influence.

According to Mr Muniu, the housing units are designed for both individual and corporate buyers, ideally as a housing scheme. For individual buyers, the project targets the middle- and upper- income brackets, through the various mortgage packages in the market.

Mr Muniu said they are also targeting East Africans in the diaspora and have sold a number of units to buyers abroad over the Internet.

A two-bedroom flat is going for Ksh2.25 million ($35,714) while a three-bedroom flat is Ksh2.65 million ($42,064). A three-bedroom bungalow will go for Ksh3.65 million ($57,937) and a four-bedroom one Ksh3.9 million ($61,905). All houses and apartment units will have separate sub-leases.

The developers are banking on the affordability, unique architecture, location and the amenities to sell the development.

"This development is one of a kind in Kenya," said Mr Muniu, adding that for comfort, the houses will feature a distinct Coastal design meant to accommodate a "21st century modern lifestyle while at the same time fitting the hot and humid weather of the Coast."