There could be some major changes in store for the upper Mississippi River.
The House of Representatives has approved an upgrade that would be the nation's costliest waterway navigation project. It is a 3.6 billion dollar undertaking to help shippers navigate the upper Mississippi and Illinois rivers.
The money would be used to replace older locks. Barge operators and farmers want to speed grain to Gulf of Mexico ports, and the Mississippi is the cheapest route for shipping corn and soybeans, coal, chemicals and construction materials.
Government scientists, however, contend that grain exports probably won't increase enough to economically justify the cost of the lock overhaul plan.
Environmental and taxpayer groups also have opposed the project.
The Senate is expected to take up its version of the proposal this summer