Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Built Environment (hierarchy name)
4. Single Built Works (hierarchy name)
5. single built works (built environment)
6. [single built works by specific type]
7. [single built works by function]
8. hydraulic structures
9. [hydraulic structures by form]

Anotations

Scope note:

Barrier on waterways such as rivers, lakes or at the seashore that incorporate sluices for controlling water levels to prevent flooding or to harness water power. For hydraulic structures that connect higher and lower sections of artificial waterways for transferring watercraft from one level to another, use 'locks.'