With these dynamics in mind, numerous federal, state, and tribal agencies in the U.S. have been working with their counterparts in Canada to reduce TDG levels. And I'm happy to say, these actions are helping out. In fact, in 2003 several improvements on Canadian projects will start to take effect.

At some Canadian and U.S. dams, additional powerhouses and turbines are being built. This allows more water to pass through the powerhouse rather than over a spillway. A nice side benefit is that these improvements can generate additional and needed electricity for homes and businesses.

Similarly, there are dams where managers are running the water through existing powerhouses even when there isn't a demand for electricity.

Structures are also being added to dams to "strip" some TDG out of the water. Spill deflectors (also called flip lips) are examples of such structures. And lastly, hydroelectric operators have found that sometimes changing which gates water flows through helps.

The transboundary gas group has an excellent web site for finding out what actions are taking place, and where.