All tests and analyses of the characteristics of waters and wastes, to which reference is made in Sections 11-4-1, 11-4-3 and 11-4-5, shall be determined in accordance with “standard methods for examination of water and sewage” and shall be determined at the control manhole provided for in Section 11-4-5 or upon suitable samples taken as such control manhole. [Prior code § 11-4-6.]