1. It shall be unlawful for any person to divert water from its natural watershed in such manner that it flows into a drainage district, or so to divert water in a drainage district as to prevent it from following the course laid out for such water by the department and cause it to flow into any stream, ditch or ditches into which it does not naturally or was not designed to flow.

2. It shall be unlawful for any person without authorization to interfere with, fill up, alter or change any drainage ditch or other structure constructed under the provisions of title 19 of this article or lawfully constructed under the provisions of the conservation or the drainage laws or any other general or special statutes, or without authorization to open or close gates or other regulating works in connection therewith or to construct unauthorized ditches or drains or other interference. This shall not be held to prevent the private construction of drainage works within a district, provided that such construction is done in accordance with plans approved by the department and with its written consent.

3. It shall be unlawful to build or maintain across or in such drainage ditch any bridge or culvert which unduly impedes the flow of water in such ditch. No bridge or culvert across or in any drainage channel or ditch within or without a drainage district and necessary to the proper drainage thereof, shall hereafter be built, rebuilt or altered by any person or authority except with the written consent and approval of the department.