Remission of rates shall only be made on recommendation of the public works committee and adopted by the city council; provided, that a consumer whose meter bill is excessive over bills of the preceding three months, and the consumer declares that his or her use of water was not in excess of previous months, the superintendent shall investigate such premises; if he finds leaky pipes and said leaks are so concealed that the consumer would not ordinarily in the occupation of the premises discover said leaks, then and in that event, the superintendent may grant said consumer credit for a part of the water so used. In the adjustment of an excessive bill caused by a leaky water pipe, or other common causes, the superintendent shall, by considering the past three months use of water, so make an adjustment that the city and the owner each shall stand one-half of the loss by leakage over and above the ordinary use of water; provided, that all pipes and fixtures on the premises shall have been immediately repaired, upon the consumer discovering, or being notified of said leak. In the event of a broken pipe caused by freezing, floods, slides, or other unforseen cause, adjustments may be made by the superintendent in conformance with foregoing paragraph, when in his judgment, proper precautions were taken to protect said water pipes from such damages.