Storm water runoff treatment system

A hydrodynamic device for treating storm water runoff, comprising:

• a first container;
• a second container disposed within the first container, wherein the first container and the second container form a first region therebetween;
• a first baffle disposed within the second container, wherein the second container and the first baffle form a second region therebetween;
• an inlet attached to or formed integrally with the second container;
• and
• an outlet attached to or formed integrally with the first container.

A hydrodynamic device for treating storm water runoff, comprising:

• a first generally cylindrical container defining a first chamber;
• a second generally cylindrical container defining a second chamber arranged about a central axis, the second generally cylindrical container disposed within the first chamber;
• a first baffle disposed within the second chamber;
• and
• a fluid inlet associated with the second generally cylindrical container such that fluid entering the device flows in a rotational pattern about the central axis within the second chamber.