The ceiling under the architect-engineer services contract is US$600m (£395m).
USAID administers the US foreign assistance programme, providing economic and humanitarian assistance in more than 80 countries worldwide.
Tetra Tech's services including design, construction supervision and related work will support USAID in providing access to clean water, sanitation, health care, schools, energy and transportation infrastructure. At the same time, it will help to build local capacity, strengthen local institutions, empower women and promote long-term sustainability.
“Tetra Tech is proud of our 40 years of service to USAID, and we are honoured to have been selected for this important USAID contract,” said Dan Batrack, Tetra Tech’s chairman and CEO. “Projects under this contract combine our international development experience and our expertise in engineering and infrastructure development to provide innovative solutions that improve the quality of life in the developing world.”