All presently installed backflow prevention assemblies which do not meet the requirements of this subchapter but were approved devices for the purposes described herein at the time of installation and which have been properly maintained, shall, except for the inspection and maintenance requirements under § 53.57 of this subchapter be excluded from the requirements of these rules so long as the Director of Community Services is assured that they will satisfactorily protect the potable water supply system of the city. Whenever the existing device is moved from the present location or requires more than the minimum maintenance or when the Director of Community Services finds that the maintenance constitutes a hazard to health, the unit shall be replaced by an approved backflow prevention assembly meeting the requirements of this subchapter at the sole expense of the water user.
('63 Code, § 5-10.109) (Ord. 469-C.S., passed 5-5-88)