In all cases in which the Board causes the demolition and removal of any building or structure to be carried out, or directs other remedial steps to be taken as may be necessary to abate the nuisance and remove the hazards, it shall be conclusively presumed that the public nuisance and the fire and safety hazard and danger to life, health or other property, created and maintained by the continued presence of the building or structure in a condition as is found to exist, constitute a clear and present danger amounting to a situation of emergency involving the public health, safety and general welfare, which requires entry upon private property for the summary abatement and removal of the danger, in the public interest.
(`86 Code, § 5-91)