Hydropower Improvement Act sponsor, U.S. Sen. Lisa Murkowski, R-Alaska speaks on the Senate floor about energy resources (oil and ANWR mainly), March 17, 2011. Image credit:Youtube
The Hydropower Improvement Act of 2011, an update of a stalemated 2010 version, "seeks to substantially increase the capacity and generation of renewable hydropower resources in the US." There's a press release posted at various locations, such as International Water Power & Dam Construction.
With US public support fading fast for nuclear power, timing of this reintroduction has to be intentional. Note: last year's version was referred to the Senate Energy & Natural Resources Committee as S. 3570: Hydropower Improvement Act of 2010, per GovTrackUS; but, no public draft of this bill, indexed now as S. 629, is yet available. Anyway, the cast of Senate supporters are from Alaska, Washington, Oregon, New Mexico, Idaho, & Rhode Island, pretty much as you'd expect.The Columbian has an opinion piece on it (someone must have shown them a draft).
How to see if you are interested and offer comments? PopVox provides a place to register organizational interest and comments. As time goes on, that site lets you track support, showing results by state on a map.
If you happen to reside in one of the States where a sponsoring senator is based, go for it.
Other than that join the Sierra Club.
This is an insiders game for the time being; and comments left here have little impact.