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2. Pre - Engineer Research and Development Center (ERDC)
3. Hydraulics Laboratory - (8/1/1972 - 9/1996)
4. Technical Publication
5. Technical Report

Title:	Design of entrance channel improvements for Ludington Harbor, Michigan : hydraulic model investigation
Authors:	United States. Army. Corps of Engineers. Detroit District. Crosby, Leroy G.
Keywords:	Breakwaters Hydraulic models Channel improvements Ludington Harbor Michigan Entrance channels Water wave absorbers Harbors Water wave experiments Design
Publisher:	Hydraulics Laboratory (U.S.) Engineer Research and Development Center (U.S.)
Series/Report no.:	Technical report (U.S. Army Engineer Waterways Experiment Station) ; H-75-14.
Description:	Technical Report Abstract: A 1:100- scale model of Ludington Harbor, Michigan, including about two-thirds of Pere Marquette Lake and sufficient offshore area of Lake Michigan to permit generation of the required test waves, was used to investigate the effects of a proposed harbor entrance improvement plan on wave action in the harbor. The basic improvement plan consisted of removing 100 ft from the outer end of the south breakwater, deepening the entrance to 29 ft over a width of 600 ft, removing the existing south jetty, and widening the inner entrance channel to 230 ft at a depth of 27 ft. Modifications to the basic plan which were tested consisted of several wave absorber designs along the inner entrance channel and raising the crown elevation of the north and south breakwaters to prevent wave overtopping. A 50-ft-long wave generator and a computer-controlled electrical wave height measuring and recording system were used in model operation. It was concluded from model test results that : (a.) the basic plan of improvement substantially increased wave heights in the entrance channel and in the vicinity of the car ferry docks; (b.) the addition of a 500-ft-long wave absorber along the south side of the entrance channel and a 900-ft-long wave absorber along the north side of the entrance channel (plan 2A) reduced wave heights in the inner entrance and in the vicinity of the car ferry docks to a level less than that for existing harbor conditions; (c.) the channel improvement plan did not significantly change existing current patterns, but current magnitudes along the south beach in the outer harbor were increased; (d.) inclusion of a rubble-mound breakwater by the small boat launching ramp in the outer basin was effective in reducing wave heights at the ramp; (e.) an additional reduction in wave heights in the entrance channel and at the car ferry docks was accomplished by raising the crown elevation of the north and south breakwaters to prevent overtopping; and (f.) raising the crown elevation of the breakwaters altered current patterns slightly (i .e ., more movement from the channel along the beaches toward the breakwaters was noted in the outer harbor).
Rights:	Approved for public release; distribution is unlimited.
URI:	http://hdl.handle.net/11681/13573
Appears in Collections:	Technical Report