Stage III (constructed between 2017-2020) - the final stage of this ambitious project - presented the contractor (Odebrecht), the owner and design team with further challenges. As Stage III was located in the remotest regions, the ability to control concrete mix designs and batching processes was complicated so the design team of Petra opted to use a combined approach incorporating both Xypex Admix C-500 NF and the Xypex Concentrate/Modified coating system on the elevated aqueducts, pump stations, flood gates and hydroelectric plants. Stage III presented other challenges as the concrete design had higher compressive strengths than the previous stages thus needing more rigorous surface preparation than before. Additionally, the extreme heat during application required strict compliance to the Xypex coatings curing procedure. Stage III used 17 tonnes of Xypex Admix C-500 NF, 45 tonnes of Xypex Concentrate and 15 tonnes of Xypex Modified.