Dr. Jeff, Izzy and Zoe tested three possible solutions to reduce flooding using the water wave machine. The evidence that helped them determine which worked best was the amount of water that flooded the area representing land. Without any barrier, they collected over 1000 mL of water. The high sea wall was better, but 300 mL was collected. With the rocks, only 100 mL flooded and even less water flooded with the recurved wall.