Construction World December 2022

SANI PASS PHASE 2 ROADWORKS (KM13,6 TO KM25) T he Sani Pass , which was bui l t in the 1950s , remains a problemat ic drive in 4x4 vehicles , wi th al l the

• Company entering: Royal HaskoningDHV • Client: KwaZulu-Natal Department of Transport • Consulting Engineers: Royal HaskoningDHV in Joint Venture with Semenya Furumele Consulting • Main Contractor: Leomat Construction • Geotechnical Consultants: ARQ Consulting Engineers PROJECT INFORMATION

chal lenges , bad weather, and treacherous condi t ions that one would expect f rom a pass wi th an al t i tude of 2 876 m above sea level . In 2005, Lesotho and South Af rica s igned a cooperat ion agreement to improve commercial , social , and economic opportuni t ies and access ibi l i ty between the SADC countries . Included in that agreement was the upgrade of Sani Pass to improve road drainage, prevent gravel loss , and l imi t eros ion caused by high- intens i ty storms and flooding. As per the agreement , South Af rica wi l l sur face the P318 up to Sani Top, and Lesotho wi l l sur face the road to Mokhot long, wi th the ul t imate goal of having a sur faced road al l the way to Maseru. The project compri ses three phases : • Phase 1 – From km 0.0 ( junct ion wi th Main Road P126 f rom Himevi l le) to km 13.6 (Good Hope Trading Post ) . • Phase 2 – From km 13.6 to km 25.0 (SA Border Post ) . • Phase 3 – From km 25.0 to km 33.0 (summi t at Lesotho Border Post ) . Phase 1 was completed approximately 12 years ago, Phase 2 was recent ly completed ( the roadworks port ion i s included in thi s submi ss ion) , and construct ion of Phase 3 i s yet to begin. Thi s submi ss ion i s for Phase 2 of the Sani Pass upgrade project . I t involves roadworks between the Good Hope Trading Store at km13,6 and the South Af rican Border Post at km 25.0. The sect ion of the P318 in quest ion begins at km13.6 at an elevat ion of 1,577m. I t general ly fol lows the

southern banks of the Mkhomazana River as i t cl imbs the escarpment in a series of steps wi th relat ively long sect ions of moderate gradients interspersed wi th short sect ions of steep gradients . Temperatures in the Drakensberg range f rom -20°C to 35°C. The area's cl imate i s defined by high annual rainfal l of 1 800 mm and severe storms in the summer months . Winter brings cold temperatures and snowfal l , and the upper sect ions of the Pass are f requent ly covered in ice. The exi st ing gravel narrow track and drainage system could not handle the high- intens i ty water run-of f on steep gradients , resul t ing in excess ive scour and gravel loss . Gravel i s a non- renewable resource, and good qual i ty gravel i s especial ly hard to come by in the Drakensberg. The eroded gravel eventual ly sett les in local streams and rivers , part icularly the Mkhomazana River, caus ing sedimentat ion and pol lut ion in the lower reaches and negat ively impact ing aquat ic biodivers i ty. Furthermore, the dust created by pass ing vehicles negat ively impacted the biodivers i ty of the adjacent vegetat ion. 

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21 st Best Project Awards 2022