Claim: Tocoma Dam in Brazil impounds the Caroni River, the country's second most important river and one of its longest.
Evidence: Tocoma Dam Caroní River The Caroní River is the second most important river of Venezuela, the second in flow, and one of the longest, 952 kilometres (592 mi) from the Tepui Kukenan, where it originates with the same name Kukenan, up to its confluence with the River Orinoco to which it belongs.