Section 7910 - Cross connections with unsafe water supplies(a) Cross connections between safe and unsafe water supply distributing systems shall not be permitted unless such connections have the written approval of the Division of Public Health.(b) No plumbing, fixture, construction, valves, fitting, device, apparatus or connection that will provide a cross connection between a safe water supply and a sewage system or will permit or make possible the back flow of sewage or waste into a water supply system shall be installed. 47 Del. Laws, c. 184, §§ 6, 7; 16 Del. C. 1953, § 7910; 70 Del. Laws, c. 147, § 21.;