Because of its sensitive location near the Prime Minister’s office, this river improvement and public greenspace project in the Ethiopian capital had to forgo typical stone blasting in favor of specialized large-scale earth blasting and excavation to remove 210,000 cu m of stone to develop key areas of the park. The approach is a partnership between a Chinese special blasting team and the Ethiopian Safety Bureau. 

Photo courtesy of CCC First Highway Engineering Group Co. Ltd. (CFHEC)

In one of those cleared areas, a cantilevered, hyperboloid, 184-m-long reinforced concrete retaining wall, 10 m high at its tallest point, was used to create an amphitheater. Multilayer wooden formwork supported the interior of the wall while shaped-steel formwork was used for the outside. BIM aided in the creation of specially shaped concrete structural steel bars, with an eye toward material waste reduction. The amphitheater design references a calla lily, Ethiopia’s national flower. To reduce environmental impacts, wastewater was treated at the site before being discharged into a sewage pipeline.

Photo courtesy of CCC First Highway Engineering Group Co. Ltd. (CFHEC)

Collaboration between Chinese and Ethiopian teams enhanced other endeavors, including a joint effort by engineers to safely transplant—using nutrient solutions, rooting and protective agents—trees and plants from a mountainous area 500 km away that were needed to create the park’s natural landscapes. The project team dug an artificial lake that is now the largest in the country. An aeolian sand anti-seepage blanket secures the lake bottom. The greenspace also houses a newly built, partially underground sewage treatment plant. Its design and footprint, smaller than is typical for Ethiopia, is being used as a technical model for future plants.

Project features include an artificial lake, fountain, waterfall, and a multi-use venue with country-specific artistic elements.
Photo courtesy of CCC First Highway Engineering Group Co. Ltd. (CFHEC)