The Westerveld Conservation Trust developed a specific ‘Contour Trenching Technique’, which consists of digging trenches of 4 meter wide and 1 meter deep, on contour elevation lines in the landscape.

The water that comes down the hills after heavy rainfalls is collected in the trenches and is brought subsurface. From here, the grounds quickly turn green with low grass. As water stays available, larger bushes start to grow and the area will stay green. The small water cycle is restored.

By doing this within a network of strategic re-greened locations the initiated evapotranspiration and atmospheric cooling ensures regular, more balanced precipitation in the entire targeted region. Within a few years, this method of climate engineering restores the ability of an extended stretch of land to provide local and regional ecosystem services.

By working with the indigenous population to develop simple and diverse business models that capitalize on the value of the re-greened land, multiple goals can be achieved. First of all, the cost of re-greening the land can be recuperated and used to re-green other areas. In that way, the initiative becomes a revolving fund instead of a “one-off-subsidy”.

Furthermore, the businesses can restart local economies, raise the social and economic standard of living, and develop a situation in which good and sustainable stewardship of the local ecosystem is encouraged, by restoring a culture of prevention.


The corridor project in Kenya
This unique method, allowing for rapid and relatively cost-effective implementation, is now being premiered in a large scale project in Kenya named the Hydrologic Corridor, from the east coast area between Malindi and Mombasa and stretching inland beyond the Kilimanjaro mountain range (i.e. 20,000 square kilometres). The project will fully restore the small water cycle in 10 individual project locations each covering an area of some 20 sq kilometres.  Two locations are to be implemented after evaluation.

At the heart of the envisoned area lies the Amboseli ecosystem , a globally important pastoral /wildlife ecosystem that is internationally recognized as a UNESCO Biosphere Reserve because of the ecosystem’s significance as an example of a conservation area that fulfills the three functions of conservation, research and development. 10.000 elephants inhabit the area of the National Parks. The last drought reduces it population from 40.000 to 10.000.

The area that is targeted- we will call it “the corridor” – encompasses a surface of approx. 20.000km2.  The hydrologic entry of this corridor is situated at the Indian Ocean at the latitude of coastal towns of Mombasa and Malindi ending in the area around the Kilimanjaro.
It is one ecological system as it forms an area where the oceanic winds flow land inwards. These are normally cooled by forested land and reaching the Kilimanjaro mountain on top of which they descend as snow.  Due to extensive deforestation this entire system is abrogated. Indian Ocean winds are not sufficiently cooled by vegetation anymore, creating torrential rainstorms generating more erosion and aggravating deforestation. This will lead into irreversible desertification and the final destruction of one of the most functional for climate regulation and beautiful wildlife regions of the world.

This process can and has to be reversed! The project proposes to implement a thought through method: by re-greening strategic spots in the area, a network of hydrogenating plots is put to work on a smoothly interrelated climatological level, finally restoring the envisaged ecological system.

The net result of the project is that by re-greening approx. 900km in approx. 20.000km2 of land can be restored into prosperous forested grassland. This size of re-habilitated land surface cover will have a major impact on the cooling of the region and Africa as a whole.
Purpose of the project
To bring a land surface cover of approx. 900 km2 in evergreen administration, resulting in the rehabilitation of the ecological system encompassing approx. 20.000km2 called the Malindi- Kilimanjaro Corridor

  • Developing a sustained and proven concept in purpose and method of climate management that can be deployed anywhere in the world in unhampered continuation
  • The work method that is introduced here combines three essential elements:
  • Deployment of hydrologic intake units adjacent to large surface water bodies
  • Deployment of a hydrologic network transmitting a rainfall to the hinterland

The places and distances of the plots are selected for their ability to interconnect at a climatological level.  Each re-greened plot creates a colon of evaporation. These colons connect into an evapotranspirational grid creating a atmospheric cooling stabilising the regional climate.
With the expansion of this evergreen network the impact on continental level will be noticeable.
This method of climate engineering will be assessed by Wageningen University and Research Center and will be authenticated as a proven method applicable all over the world thereafter.


Project partners

  • Kenya Wildlife Service, National Park Management
  • Olgulului Group Ranch, landowner and business partner
  • Imbirikani Group Ranch, landowner and business partner
  • ICRAF Word Agroforestry, Scientific Research partner
  • Fleckvieh Nairobi, Business partner cattle
  • Royal Haskoning / DHV, Operational business partner
  • Triodos Bank, Banking partner
  • Wageningen University, Scientific Research partner