This powerpoint presentation begins by listing common types of water storage tanks, and states that all types have unique challenges with short-circuiting and mixing from geometry and typical inlet/outlet (I/O) piping. It states that maintaining water quality in reservoirs takes a combination of mixing system design and operation/fluctuation of the tank. It mentions a 2006 AwwaRF Project on 3DLIF scale modeling titled, "Physical Modeling of Mixing in Water Storage Tanks" by Philip J.W. Roberts et al. Topics outlined include: short-circuiting; hydrodynamic mixing; empirical mixing time equation; mixing time equation is limited to same inlet and tank water temperature; effect of temperature differential between inlet water and tank water; TIDEFLEX "Duckbill" Check Valves; why Duckbill Manifolds are utilized; and, optimized Duckbill Manifold configurations - circular and rectangular reservoirs. Includes figures.