NARBERTH, PA — Waves of muddy water cresting at heights from four to seven feet swept parked cars from their driveways into Mill Creek — and took out the entire Narberth cruiser fleet while they were at it. Among the flood's casualties were the entire fleet of four Narberth patrol cars, another two Lower Merion patrol cars costing more than $25,000 each, Narberth police department's $9,000 speed signal display, extensive damage to Hollow Road pumping station, and at least one Bala Cynwyd business. Narberth Police Lt. Arthur Pavoni said his officers are now patrolling the borough in borrowed Lower Merion patrol cars "Until we can get some new ones in. All four police cars are going to be a total loss. None of them are usable." The cost, said Pavoni, would be about $20,000 per patrol car, but add onto that another $8,000 to $9,000 per car to equip it with all the necessary police radios and equipment.