Publication Detail

Morphodynamics of Tidal Inlet Systems in Maine

Duncan Fitzgerald, Jonathan M. Lincoln, L. Kenneth Fink, Dabney W Caldwell
19 pp.
MITSG 91-02J

The occurrence of tidal inlets along the coast of Maine is tied closely to the structural geology and glacial history of this region. Most of the inlets are found along the southern shoreline where sand sources were sufficient to build swash-aligned barriers between pronounced bedrock headlands. Along the peninsula coast of Maine, tidal inlets also occur at the mouths of the Kennebec and Sheepscot Rivers where large quantities of glaciofluvial sands were deposited during deglaciation. The hydraulics of Maine's inlets are controlled by their size. Small and medium-sized inlets are dominated by flood tidal currents due to a longer ebb than flood duration. This duration asymmetry is the result of both frictional effects and a truncation of the tidal wave by the shallowness of the entrance channel. These conditions are much less apparent at large inlets which have stronger ebb tidal currents. The ebb dominance of these inlets can be explained in terms of inlet efficiency and filling characteristics of the backbarrier. The mouths of the Kennebec and Sheepscot Rivers are normally tidally dominated (excepting spring freshets), while the Saco River mouth exhibits stratified flow and more estuarine conditions. The history and mechanism of inlet morphogenesis and hydrodynamics are examined.

type: Technical reports

Parent Project

Project No.: 1986-RC-21-PD
Title: Management Guidelines for Tidal Inlet Shorelines for Maine