The city in which the fire hydrant is located is liable for the property damage (cost of repairs) to your car.Contact the city's claims department and be sure to follow all of their procedures for filing your property damage claim.  If you don't follow their procedures or miss a filing deadline, your claim will be denied.If the city denies your claim despite you complying with all of their procedures, you can then file a lawsuit against the city for negligence and seek compensation for the cost of repairs to your car.