The Supreme Court has ruled, the fat lady has sung, in the PPL Montana vs. the State of Montana case. The Supreme Court overturned lower court rulings that the “Great Falls” section of the river, and possibly other disputed sections, were navigable, and therefore that the riverbed was owned by the state. A key point of the decision was that navigability must be determined on a section by section basis, not on rivers in their entirety.
The decision laid out some legal principles which could have repercussions in North Carolina. Basically, it enumerated three distinct issues:
1. The title to riverbeds is determined under the equal-footing doctrine. The State owns the riverbed if that section of the river was navigable in the customary mode of trade and travel under natural and ordinary conditions at the time of statehood. For NC, that was 1789. This is based in the U. S. Constitution and is interpreted by federal case law. (In NC, riverbeds that are not navigable and therefore not owned by the State are owned by adjoining property owners.)
2. The pubic trust doctrine applies to the public's right to use the waters of rivers for fishing, boating, swimming, recreation, etc. This is governed by state law.
3. Admiralty jurisdiction gives the federal government the authority to regulate waters which have become navigable since the date of statehood, or which could become so by reasonable improvements.
The Pee Dee River has always been widely regarded as navigable from its mouth to Cheraw, SC, and is still so regarded by the US Army Corps of Engineers. The report of the Army Corps regarding the upper Yadkin River, from Wilkesborough to near Salisbury, in 1879, which the Yadkin Riverkeeper previously produced, concluded that that section of the river could be made navigable with improvements (i.e., it was not navigable in its natural condition at the time of statehood).
The Army Corps also reported on the lower Yadkin - upper Pee Dee River in 1888. That report concluded that the entire section of the river from near Salisbury to the SC line was unworthy of improvement [to make it navigable]. The report also noted that that section of the river was more suited to the development of water power than navigation, and that local citizens were more interested in fish having free passage up and down the river.
The Yadkin River has not been found to have been navigable by boats used in 1789 in its natural and ordinary condition at the time of statehood (1789), and is therefore not owned by the State. This is what Alcoa has said all along. Alcoa bought, paid for, pays property taxes on, and owns the riverbed under their project. The people of NC and the riparian owners have the right to use the waters of the river, and significant time was spent during the relicensing process on developing license terms to accommodate and enhance public use of the river.
I haven't checked it all out, but I assume Progress Energy owns the riverbed under their section of the river, and that other adjacent landowners own the remainder of the riverbed. Here's a good explanation of Water Law in North Carolina.
yadkin river of opportunity riverofopportunity.com