If you have a water purification filter you wont have to take all your water with you. Tons of spots to refill bottles along the Sespe River. The map I use for that area is the Tom Harrison map of the Sespe Wilderness.They might have it at the Ranger station at Wheeler Gorge on the Hwy 33 on your way to the Piedra Blanca Trailhead. You can camp right next to the tub if its not busy. There is a drain you can open on the bottom of the tub to drain the old water and refill it with fresh water but it turns white quickly. I love this spot have fun!