CFR›Title 40›Chapter I›Part 450 ContainsSubparts A–BCorpusDaily eCFRDisplayed edition2026-04-27Last updated2026-04-27 PART 450—CONSTRUCTION AND DEVELOPMENT POINT SOURCE CATEGORY Subparts A Subpart A—General Provisions Sections 450.10–450.11 B Subpart B—Construction and Development Effluent Guidelines Sections 450.21–450.24 Authority33 U.S.C. 1311, 1312, 1314, 1316, 1341, 1342, 1361 and 1370.Source74 FR 63057, Dec. 1, 2009, unless otherwise noted. Previous 449 Part 449—Airport Deicing Point Source Category Next 451 Part 451—Concentrated Aquatic Animal Production Point Source Category