Related Clues:

• Glen Canyon ___
• Job for a snake
• China's Three Gorges ___
• Stream obstruction
• Beavers' structure
• Beaver-built barricade
• River restraint
• A mad animal mum
• Shut out, obscure
• Cod clue to shut out
• Stop up, obstruct
• Barrier to hold back water
• Water retainer
• Mother of quadruped
• Barrier against water