Try this to get the information from the horse's mouth and avoid paywalls altogether.
https://vapassengerrailauthority.or...d Long Bridge Project,VA, and Washington, DC.Embedded with the above is a link to the ROD (Record of Decision) with lots of detail. I have not read it and may never. Appears to be the usual 95 pages of fluff with 5 pages of real information. Near the bottom is an aerial with the alignment. I have suffered through too many of these things when I had to. (I have also long since given up on considering the Washington Post anything but a bird cage liner way overimpressed with themselves.)
Then there is this:
https://railroads.dot.gov/elibrary/...appendix-b-section-106-programmatic-agreement
This is over 200 pages, again primarily a cure for a severe case of insomnia. The long winded title is, "PROGRAMMATIC AGREEMENT AMONG THE FEDERAL RAILROAD ADMINISTRATION, THE DISTRICT OF COLUMBIA STATE HISTORIC PRESERVATION OFFICE, THE VIRGINIA DEPARTMENT OF HISTORIC RESOURCES, THE NATIONAL PARK SERVICE,
NATIONAL CAPITAL PLANNING COMMISSION, AND THE VIRGINIA DEPARTMENT OF RAIL AND PUBLIC TRANSPORTATION REGARDING THE LONG BRIDGE PROJECT IN WASHINGTON, D.C. AND ARLINGTON COUNTY, VIRGINIA". Seeing all the preservation, planning, and historic association names listed just tells us it will be entirely fixated on visual issues, with the general mindset that all would be negative. There are things in these that leave me thinking some of these people are seriously demented. There is a list of "Historic Properties" that begins on page 32 of the pdf file. In that list, item 33 is the "Richmond, Fredericksburg and Potomac Railroad Historic District" described as being "Along CSXT right-of-way in VA from Arlington County to the City of Richmond, VA"!! What?? The entire railroad is a historic district. This has to be driving CSX nuts.
In this document, going to pages 37 and 38 of the pdf file we have a letter from the GOVERNMENT OF THE DISTRICT OF COLUMBIA STATE HISTORIC PRESERVATION OFFICER where they recommend use of multiple through plate girder spans to be visually similar to the existing railroad bridge. Why oh why? So everything looks like it was built in the 1920's? When I was still there working on WMATA and their bridge parallel and between the existing highway and railroad bridge was built, I thought at the time two more tracks for the railroad would be good, and the new railroad bridge should be looking like the WMATA bridge. Then it would be nice to replace the existing railroad bridge with a similar looking structure. Being deck structures rather than through structures would be nicer for everyone and a solid deck with direct fixation track would be quieter and lower maintenance. Just for info, the WMATA bridge had a grade of 0.2% up toward the middle with a very long vertical curve at the crest which is a profile that would be quite feasible for freight.
By the way, the through truss draw span in the existing bridge is non-functional. It has been locked down for years.
Another random piece of information: The state line between Virginia and the District of Columbia and with Maryland is the low water south side of the Potomac River. Also, pre multiple merger days, the change of track ownership between the Pennsylvania Railroad and the RF&P was at the same point, or possibly the south end of the bridge itself. Either way, consequently, the RF&P was entirely within Virginia. When electrified, the power necessary to get freights into Potomac yard was owned by the PRR even though the track underneath was owned by the RF&P.