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The 2016 Drainage Manual is the current standard, in use since December 31, 2016. Prior to that, the 2009 Drainage Manaul was the standard, and before that, the 1994 Drainage Manual.
The 2009 manual contained special provisions relating to development in the Salmon Creek Drainage Basin (beginning on page 271); the Green Cove Creek Basin (beginning on page 295); and the McAllister/Eaton Creek Basin (beginning on page 308).
Entire 2009 Drainage Manual (PDF) | Individual Volumes of the 2009 Drainage Manual | Documents Related to the 2009 Drainage Manual | 1994 Drainage Manual (PDF)