These wetlands are complexes of Lyngbye's sedge (T6) and Alkaligrass (T4; usually Puccinellia grandis or P. Hulténii), and, in the case of  T4-6, Ramensk's sedge (T5; Carex ramenskii) components.  The component covering the most ground is named first, except in the case of  the single T4-6 wetland at the mouth of the Swanson River where all three components are present at greater than 10% ground cover.  These components are inundated by the tide relatively infrequently, but all retain water for days following flooding (Vince and Snow, 1984).

A T46 and the single T64 wetland are adjacent, just west of the Warren Ames Memorial Bridge at about river mile 4.5 along the Kenai River.  The single T4-6 and the other T46 wetland occur at the mouth of the Swanson River.

The T4 component loosely corresponds with Vince and Snow's 'Outer Mudflats Zone 2', estimated to be inundated on higher spring tides, or an average of 15 times per summer on the Susitna Flats (with a range of 10-20 times per summer), in upper Cook Inlet, Alaska.  Vince and Snow found that water was retained for 2-5 days per inundation.

The T5 component corresponds with Vince and Snow's 'Outer Sedge Marsh Zone 3', estimated to be inundated on only the highest spring tides, or an average of 3 times per summer on the Susitna Flats (with a range of 0-5 times per summer), in upper Cook Inlet, Alaska.  Vince and Snow found that water was retained for 2-3 days per inundation.

The T6 component corresponds with Vince and Snow's 'Inner Sedge Marsh Zone 7', estimated to be inundated on only the highest spring tides, or an average of 2 times per summer on the Susitna Flats (with a range of 0-5 times per summer), in upper Cook Inlet, Alaska.  Vince and Snow found that water was retained for greater than 5 days per inundation.