Was the Lewis and Clark journey successful?

The expedition's goal as stated by President Jefferson was "to explore the Missouri River, & such principal stream of it as, by its course & communication with the water of the Pacific ocean may offer the most direct & practicable water communication across this continent, for the purposes of commerce." In addition, the expedition was to learn more about the Northwest's Natural Resources, inhabitants, and possibilities for settlement. They were able to prepare 140 maps, document over 122 species of animals and 178 plants and achieve friendly relations with the Native Americans they encounters; however, they did not find an all-water route to the Pacific Ocean.