Assertion: tower's structure | /r/CapableOf | rely to keep phreatic surface
Facets:
value: on a pervious foundation
type: LOCATION
value: to a minimum
type: TRANSITIVE-OBJECT
value: generally
type: DEGREE
Source sentences:
text: They are only suitable for downstream and centreline dams as upstream structures generally rely on a pervious foundation to keep the phreatic surface to a minimum, and thus increasing impoundment stability (Vick 1990).