Answer: impounding

AnswerCrossword Clue
impounding(of a dam) Hold back or confine (water)
impoundingIMPOUND, to seize and retain in legal custody
impoundingSeize and take legal custody of (something, esp. a vehicle, goods, or documents) because of an infringement of a law or regulation
impoundingShut up (domestic animals) in a pound or enclosure