N.D. Cent. Code § 49-06-07
If, within thirty days after the service of the order, as set forth in section 49-06-06, the public utility fails, neglects, and refuses to file a bond or undertaking with the commission, then the commission immediately shall fix, determine, and prescribe temporary rates to be charged by such public utility pending the final determination of said rate proceeding. The temporary rates, so fixed, determined, and prescribed shall be sufficient to provide a return of not less than five percent per annum upon the original cost less accrued depreciation of the physical property of said public utility used and useful in the public service. If the duly verified reports of said utility to the commission do not show the original cost, less accrued depreciation, of said property, the commission may estimate said cost less depreciation and fix, determine, and prescribe rates as hereinbefore provided. In determining the original cost or in estimating the cost as herein provided, the commission may take into consideration any report, annual or otherwise, filed with it by any utility, together with any other fact or information which the commission may acquire or receive from an investigation of the books, records, or papers of such public utility and from an inspection of its property, or from the examination of any report, annual or otherwise, made by the public utility and filed with the state tax commissioner, or any report, annual or otherwise, made by the said public utility to the federal power commission, federal communications commission, or federal securities and exchange commission.
N.D.C.C. § 49-06-07