Rap in Arrow Canyon Damn?

Hi all, I had thought I'd heard a whisper that there's a way to get to the Swamp Cave without the slog through the canyon (albeit a pretty cool slog).  I have a group that I'd like to take to the Swamp Cave later this month and wondering if the rumors of a shorter approach (4x4 roads no problem) by rapping in from the damn are true?  Looking at Google maps it looks like there may be some access roads that come near the damn from the south but I don't want to spend a whole day trying to find the approach beta with a limited time window.  

Any help/beta most appreciated.

-Ben

Dam dude. 

Well, technically:

“Dam, dude!”

The info you seek is in the Mojave Limestone guidebook.  But having done the rappel approach, I will offer the following:

1. While you will save hiking time, you will not save any overall time.  It takes longer to drive to, drive out, and is especially tedious to ascend back out if people in your party don't know how to jumar.  On that note, take a rope to jug just in case the one currently in place is missing or in poor shape.

2. Take a vehicle that you don't care about any scratches.  The BLM has not done a great job of maintaining that road.  Your vehicle will be scratched.  A lot.

3. Parking is at a premium.  There may be 3 spots total.  Although I doubt it's ever crowded.

4.  Approach is from the northwest on an unmarked road, not the south.

Absolutely do not go out that way if it has rained recently. I attempted to access it after recent rains, and the dirt road was a horrendous mud pit. We had to park pretty early before actually reaching the dam. Additionally, the dam was filled with water once we walked through all the mud. We managed to circumvent the dam with some scrambling, but it wasn't worth it because there was more water in the canyon below. We ended up bailing before ever getting to the wall. I think it had been raining for a few days before this so I'm sure it would be fine if it hasn't rained recently, but I won't ever try to access from that side again. It's a nice walk and straightforward approach if you just go the standard way.

Appreciate the beta, everyone, and sorry about the poor spelling.  With everything said above it looks like I should probably just hike in.  Everyone is a climber for the most part so not worried about that part but I do have a pretty nice truck that I'm not looking to scratch up.  

This is for a bachelor party with a few trad climbers so I was trying to make the sport-wanker approach as easy as possible given our presumed fatigue.  It's a beautiful hike once you get to the canyon, though.  I don't have the Mojave Limestone book, just the limestone bible.  

Thanks again, everyone.