While lawmakers look ahead and review spending proposals in the next federal budget, Michigan U.S. Senator Carl Levin says the Great Lakes should be high on the priority list.

Already in place is the Great Lakes Restoration Initiative. Levin calls that an important effort that not only helps protect the Great Lakes but works to preserve them as well. Supporters say a healthy water system is essential in order to maintain environmental stability.  With so much of the state's tourism and recreation economy tied the lakes, they say keeping them in good shape will help assure economic vitality.

Of the entire world's fresh water supply the Great Lakes make up 21% of it.

Michigan U.S. Senator Carl Levin - Photo by Getty Images