(a) Persons authorized to construct or to repair highways may make or clear any watercourse or place for draining off the water therefrom into or through any person’s land so far as necessary to drain off such water and, when it is necessary to make any drain upon or through any person’s land for the purpose named in this section, it shall be done in such way as to do the least damage to such land.

(b) Nothing in this section shall be so construed as to allow the drainage of water from such highways into, upon, through or under the yard of any dwelling house, or into or upon yards and enclosures used exclusively for the storage and sale of goods and merchandise.