I've fished it several times in my kayak. I've only done the 20 miles from hwy 16 to hwy 4 once. All the other times I've put in at hwy 16 and either gone up river to the dam or down river about 3 or 4 miles and back. Fishing is great and it's a beautiful place. If the flow is under 250 cm and you did the 20 miles down river you may have to drag or walk your raft thru some shallows but none over 50 yds, most under 10 or 20. Not what I would call an actual portage tho. You would never be on dry ground, just some places where you would be pulling over a shallow gravel bar or some shallow, larger rocks. It's a fun river. I would do it in that boat. I just bought a canoe and will probably be taking it down there next month for another 3 day trip (even tho I said I wouldn't do another one after my last trip). Here's my post from that trip https://r.tapatalk.com/shareLink/topic? ... source=app
After thinking about it. That boat may be difficult to navigate a few areas where there's longer, narrow stretches (maybe a hundred yds long) that have a some low over hanging trees and such. They're plenty deep enough but kinda narrow for that raft and the trees would add to the difficulty. I still think it's quite doable but may be a little more effort than you're looking for.
And heres a link to check water flow below PK
USGS Current Conditions for USGS 08088610 Brazos Rv nr Graford, TXhttps://waterdata.usgs.gov/tx/nwis/uv/?site_no=08088610
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