Section 9. Whoever, by himself, his agents or servants, deposits in or along any ditch or drain constructed under section four any material which will obstruct the flow of water therein shall be punished by a fine of ten dollars, and shall be liable in tort to the commonwealth, the county, city or town controlling the ditch or drain for all damages caused thereby, for the cost and expense of removing the obstructing material and of restoring the ditch or drain to its former condition.