https://www.assetstore.unity3d.com/en/#!/content/52103
AQUAS is a full featured water system for Unity. It's designed not only for the looks but also for high performance to keep as many resources free for demanding graphics.
For more info please visit the particular asset store pages:
Gaia: https://www.assetstore.unity3d.com/en/#!/content/42618
World Creator: https://www.assetstore.unity3d.com/en/#!/content/55073