So I bought a Tracker 175 last month and two days after getting it took it down to Lake Marion. Went into Stumphole with raised motor and idled to the places I've found these last few years back in there. No problems. Pretty slow fishing so decided to go to Jacks Creek, where I've never been because I've never felt entirely comfortable on that bigger water in my Gheenoe. Long story short, I got out of the river channel (which I think is poorly marked) and realizing I was in 6 feet of water, slowed to just above idle but didn't raise the motor and hit a stump at less than 10mph destroying my prop. It took 2 hours to limp back to Stumphole landing, and a trip to Columbia to get a new prop and salvage the weekend trip.

Can someone clarify the navigation hazards, specifically the rock piles, at either end of the canal? Also, I understand red and green navigation bouys, but do not understand the poles with square placard on top, some with numbers, most with nothing.
If I'm not mistaken, on most lakes an underwater obstacle is marked with a white buoy/orange diamond. I realize as well, that Lake Marion is one big underwater hazard and no way can they mark everything. There are rock piles on each end of the canal and on both sides as I understand. A friend told me if going from the canal to Moultrie, "Don't get out of the 'lane' because there are rock piles just under the water. On the other end, outside of the canal toward Harrys near the Marion dam there are several markers that say "ROCK" but is that it? Do those poles identified only with a number indicate an underwater hazard?

Is there any newer maps or software that offers some level of safe navigation or am I missing something, or is that just the hazard of fishing the Santee lakes?

I've puttered all over up in and near Stumphole in my little Gheenoe with a 9.9 hp but suddenly feel helplessly in danger of prop and engine damage in this newer boat. Yet I see people running at speed in bass boats, center consoles, deep V's etc. Am I missing something obvious?