In making any excavations in any street, alley, or public place, Company, its successors and assigns shall protect the site while work is in progress by guards, barriers or signals, shall not unnecessarily obstruct the use of the streets, and shall back fill all openings in such manner as to prevent settling or depressions in surface, pavement or sidewalk of such excavations with same materials, repair of any defects caused by the Company, and restore the affected property to its original condition as nearly as practical, subject to City ordinances and design standards, provided such ordinances and design standards are commercially reasonable.