Impoundment of vehicles under the authority of the provisions of this article shall be construed as an enforcement procedure for protection of the public peace, safety, welfare and safeguarding of property, and shall be used generally for the prevention and removal of traffic hazards, prevention and abatement of public nuisances arising from traffic law violations, protection of the public rights in the use of streets and thoroughfares in the city, from obstructions placed and left in derogation of those rights, and for safeguarding and protecting recovered stolen vehicles.