After an excavation is commenced, the permittee shall prosecute with diligence and expedition all excavation work covered by the excavation permit and shall promptly complete such work and restore the street to its original condition or as near as may be so as not to obstruct the public place or travel thereon more than is reasonably necessary. In no case shall the excavation extend more than 30 days under the permit hereunder unless the permit is specifically renewed by the City Commission.
(1990 Code, § 4.20)