No county, city, town or other public body, or person shall discharge, or suffer to be discharged, directly or indirectly into any waters of the district any sewage, industrial wastes or other refuse which may or will cause or contribute to pollution of any waters of the district, provided, that this provision shall be applicable only to such part or parts of the waters of a district as shall be bounded and described in a notice, published in a newspaper or newspapers having, in the aggregate, general circulation in all of the counties and cities within which or bordering upon which such part or parts of the waters of the district are located, to the effect that the commission has provided facilities reasonably sufficient in its opinion for the disposal of sewage, which by discharge from public sewer systems might cause or contribute to pollution of the bounded and described part or parts of such waters, and that pollution of the same is forbidden by law. Such a notice shall constitute prima facie evidence of the existence of facilities sufficient for the disposal of such sewage. The provisions of this section shall not prohibit the disposal of sewage and industrial wastes in the manner in which the same is now being disposed of, or in any other reasonable manner, by any county, city or town, no part of which constitutes a part of any district, or by any person in any such county, city or town, no part of which constitutes a part of any district.