How to Fill Sandbags
Fill the bags one-half to two-thirds full. The bag, when filled, should lie fairly flat. Over-filled bags are firm and don't nestle into one another; tight bags make for a leaky sandbag wall. Tying is not necessary.
How to Stack Sandbags
Stack sandbags so the seams between bags are staggered. Flip the top of each bag under so the bag is
sealed by its own weight.