Ecologically, C. fluminea can outcompete many native clam species for food and space (PNNL 2003). The introduction of C. fluminea into the United States has resulted in the clogging of water intake pipes, affecting power, water, and other industries. Nuclear service water systems (for fire protection) are very vulnerable, jeopardising fire protection. In 1980, the costs of correcting this problem were estimated at 1 billion dollars annually. C. fluminea causes these problems because juveniles are weak-swimmers, and consequently they are pushed to the bottom of the water column where intake pipes are usually placed. They are pulled inside the intakes, where they attach, breed, and die. The intake pipe become clogged with live clams, empty shells, and dead body tissues. Buoyant, dead clams can also clog intake screens.
Location Specific Impacts:
Competition: The indigenous C. leana has disappeared in the Yodo River in the Lake Biwa-Yodo river system. The authors suggest that the invasion of exotic C. fluminea may result in the extinction of the indigenous C. leana.