Although a larger channel will increase friction presented to the flow within
it, it can be inferred that alignment of the channel almost parallel to shore makes
the inlet an efficient bypasser during ebb flow. At that stage of tide, an ebb
current of any strength would reinforce wave action and the wave-induced
longshore current directed to the east to transport material down the coast.
Therefore, it may be feasible to maintain the inlet with less dredging by allowing
the channel to remain oriented toward the east than it is to dredge and realign the
channel straight out toward the sound. Likewise, the orientation toward the east
makes it difficult for sediment streaming off of the spit on the east side of the
jetty to turn almost 180 deg and enter the inlet entrance.
Finally, development and maturation of the existing flood shoal has served to
block sediment transport into Goldsmith Pond, resulting in sediment deposition
within the channel since 1993. The limiting depth that has resulted from the
development of this feature has also served to accentuate asymmetries in flood
and ebb current velocity (discussed in Chapter 5). At present, given the rapid
eastward migration of the inlet entrance and the apparent increases in in-channel
sedimentation rates, Goldsmith Inlet can be said to be an autonomic system,
where changes within it promote a positive feedback cycle, thereby increasing
the observed rates of change. Maintenance of the inlet mouth in an eastward
orientation may only require minor dredging, thereby reinforcing the autonomous
behavior. An eastward orientation would maximize sediment bypassing while
allowing a minimal amount of sediment to enter the inlet channel.
Chapter 4 Morphology Change, and Channel Shoaling and Migration