The indie retailer's water bottling business Montgomeryshire Natural Spring Water Company was named Supreme Supplier of the Year and Ethical Supplier of the Year.
It produces The Co-op's own-label water Fairbourne Springs from a bottling plant on the grounds of its HQ in Churchstoke on the Welsh borders.
A percentage of sales from the brand funds PlayPump water pumps in Africa that double as children's roundabouts.
The Co-op and Somerfield customers have provided drinking water for one million Africans as a result of the initiative.
Montgomeryshire also bottles water for Musgrave Retail Partners GB and Nisa-Today's. It beat suppliers including Coca-Cola and Heineken to the award.