Muddy Waters

 is a challenge in Survivor. It premiered in  and reappeared in  as a post-merge reward challenge.

Rules
The contestants are divided into equal teams. One at a time, they race through an obstacle course. They crawl under a low cage (or walk across a series of balance beams), clamber up a steep slope and slide down into a mud pit. They then search for a bag of balls buried in a designated mud pit. Upon retrieving the bag of balls, the contestant crawls under a wooden bar by digging through a pit of rice. Upon reaching the mat, the next team-mate may begin the course. Once all teammates have reached the end, the balls must be thrown into a narrow tube about as high as a basketball hoop. The first team to sink all their balls into the tube wins the challenge.

Survivor: Philippines
This challenge debuted in as a reward challenge in Little Miss Perfect. Jonathan Penner pioneered the strategy of finding all the ball-bags in the mudpit and placing them in a corner, allowing the contestants that followed to simply grab a bag of balls on their way through. The strategy gave his team a strong lead, and Penner, Carter Williams, Denise Stapley and Malcolm Freberg won the challenge.

Survivor: Caramoan
The challenge reappeared in, again as a reward challenge, in Zipping Over the Cuckoo's Nest. Malcolm Freberg utilised Penner's successful strategy from the previous season to find all ball-bags in one go. However, the opposing team adopted the strategy partway through the challenge, and Reynold Toepfer found all the bags first. This gave Reynold, John Cochran, Dawn Meehan, Erik Reichenbach and Phillip Sheppard a lead, and they won the challenge.

Trivia

 * This challenge was used in both seasons filmed in the Philippines.
 * This challenge has only been used as a post-merge reward challenge.
 * Malcolm Freberg is the only contestant to compete in this challenge twice.