When at least seventy percent of the qualified electors who are owners or part owners of land bordering on any existing or proposed road or highway have signed the original petition and thereby released all their claims to damages arising from altering, discontinuing, or laying out such road or highway, it is not necessary to post copies of the petition as provided for in section 24-07-09, nor to post notices or serve notices as provided for in section 24-07-10, except that the notices must be served personally or left at the abode of such occupants as may have failed to sign the petition and whose land borders on the road or highway proposed to be opened, altered, or discontinued. The general knowledge, and the fact, that seventy percent of the qualified electors have signed the original petition in compliance with this provision must be deemed sufficient notice to all concerned and for all intents and purposes.