The owners of at least ¾ of the assessable area of the assessment district shall not be required to present sealed proposals, but may upon making an oath that they are such owners, within 10 days after the publication of the notice of award, elect to enter into a written contract with said director to do the whole work specified in said award at the price or prices at which the same has been awarded.
Should such owners not enter into such a contract for said work within said time the awardee to whom the contract has been awarded shall enter into a contract for said work within seven days after the expiration of the time within which said owners might have entered into a contract for the same.