In his book "The Untold Story of Shiloh: the Battle and the Battlefield", Timothy Smith, a staff member at Shiloh NMP writes on page 22:
"Similarly, the entire Bloody Pond phenomenon could be a myth. There is no contemporary evidence that indicates that the pond became blood-stained. In fact, there is no contemporary evidence that there was even a pond on this spot. The sole account came from a local citizen who years later told of walking by a pond a few days after the battle and seeing it stained with blood."
On page 149 he wrote:
"For example, Reed (appointed secretary and historian of the newly created Shiloh NMP on March 26, 1895) marked the Bloody Pond, which is today one of the most popular sites in the park. However, no after-action report mentioned the pond, and the account of bloodstained water came only from a local resident who walked the field after the battle. In addition, other people reported similar instances of bloodstained water at other locations. But Reed marked this particular pond, and it has become known to history as Bloody Pond"