According to an item in the Marine Business Journal, a legal decision
in a lawsuit pressed by a group called "Northwest Envionmental
Advocates" has potential implications for every pleasure boater
operating in US waters.

In an effort to prohibit the discharge of ballast water from foreign
vessels (and reduce the liklihood of introducing foreign plants and
animals to local eco-systems) the Environmental Advocates sucessfully
argued that any vessel discharging any liquid or material of any type
must first obtain a permit from the state in which the discharge is
going to take place. (As a condition of granting the permit, most
states will demand the right to inspect the vessel, ensure that all
available pollution controls are installed and properly maintained,
and may even want to monitor the discharge- at the vessel's expense).

One small oversight: Unlike previous versions of similar regulations,
the legal ruling does not exempt pleasure vessels from the requirement
to obtain a discharge permit.
As a result, everything from cooling water cycling through an engine
to water running off of a deck can be considered a "discharge" and is
technically subject to state permit!

The NMMA is lobbying congress for a revision of the law.