ARQ & Partners provides specialist structural engineering solutions where conventional solutions appeared too costly. Wadi Minqal road crossing presented considerable challenges since the roadway passes relatively high over the wadi bottom necessitating high and therefore costly piers if conventional construction techniques are followed. In addition, the wadi bed consists of non-uniform deposits including deep clays that results in additional foundation costs. The Contractor, Strabag, approached our team to develop an alternative solution and we designed a structural steel arch bridge to avoid the high piers and poor founding conditions in the wadi. The bridge abutments also presented difficult founding conditions, as investigations revealed extensive cavities in the limestone rock mass, which required consolidation grouting to limit settlement under load. Considerable cost savings were also introduced in reservoir design by the simple method of considering the reservoir roof as a structural tie, transforming the walls from cantilever walls to propped cantilevers with associated savings in material costs.