There are some low areas in loop 3 that collect water pretty easily. Stay off of the trail for a few days after a good rain to make sure that you don't ruin anything and can make it all the way through.
Trail is broken up into 3 sections. Loop 1 is a short, fast, starter loop with some twists and turns but not very hard at all. Loop 1 is approx 0.6 miles long.
Loop 2 is a little longer and more challenging. 1.5 miles of pretty open singletrack with 4 log pile obstacles with the occasional "optional" route to hit a few log hops. A generally flat and fast section. Links right back up with the start of loop 1 or you can continue on to loop 3.
Loop 3 is the most challenging loop at Bass River. Tight, technical sections in the beginning followed by some flowy hills and burms. This section has more climbing to it but the hills are generally small and you can get up them pretty easily. The end of this loop connects back to where loop 2 ended and where loops 1 and 3 begin. Loop 3 is approx 2.1 miles long.
Aside from the singletrack aspect of it there are a lot of the two-track areas from 4-wheel drive vehicles that have been made over the years that are fun to explore. You can ride back into the recreational area for miles and never hit the same road/two track. There are trails that take you by the Grand River, basins, larger hills, rock gardens, and forest.