IV. Retreating Shorelines
231.
As said earlier, beach nourishment has been eyed by the U.S. Army Corps of
Engineers as a method to dispose of the 265.5 million m 3 (300 million cu.yd) of
dredged material it picks up annually. This material is usually dumped at sea
damaging benthic life. Such disposal can also help portuary development and
marsh creation. Under the proper circumstances the use of dredged material for
beach nourishment not only contributes to the development and maintenance of
waterway transportation, but also provides hazard reduction and recreational
benefits consistent with environmental mandates and the material laws governing
coastal systems. Beach nourishment is the least-cost environmentally acceptable
disposal alternative. Despite its current prevalence, beach nourishment cannot be
considered a panacea for dredged material disposal ills. For three out of every
four navigation projects, the dredged material is not a practical, cost-effective,
and permissible source for beach nourishment supply. Most frequently, the
material is too fine-grained to be effective for shore protection. Other constraints
are excessive cost, unallowable environmental effects, and technical limitations.
3.1.4
Nature of "Beach Fill"
Material to be used, carefully selected as to nature and source site, may be
brought to the beach to be restored and dumped offshore, leaving it to the sea to
carry it to the shore and insuring its geographical distribution. It may also be
deposited at a single location on the beach; called stockpiling, it allows the
artificial supply point to act as a distribution center or feeder beach. Still another
approach is to spread directly the material on the endangered beach, restore it
stande pede and take simultaneously appropriate "soft" measures to protect it.
Finally the continuous supply method involves creation of a fixed, or semi-fixed
plant which first intercepts and then passes on the littoral drift to the down-drift
side.
In some cases a combined approach has been taken, e.g. offshore dumping and
on-shore nourishment. Beach nourishment has even been called upon to restore
lake beaches, for instance in the Province of Qu6bec (Lac St. Jean).
The beach nourishment approach has been also used on lakes shorelines ; this has
been the case at Lac St. Jean in Canada and on the shores of Lake Michigan, for
instance in Evanston, Fort Sheridan, Highland Park, Lake Bluff, Illinois Beach
State Park and at several beaches of Chicago (Illinois).
Sand nourishment of Chicago beaches between 1961 and 1964 involved
deposition of 381.000 m 3 (498.300 cu.yd).
While the technique is the same for lake and oceanic beaches there are some
environmental differences to be reckoned with.
231.
As said earlier, beach nourishment has been eyed by the U.S. Army Corps of
Engineers as a method to dispose of the 265.5 million m 3 (300 million cu.yd) of
dredged material it picks up annually. This material is usually dumped at sea
damaging benthic life. Such disposal can also help portuary development and
marsh creation. Under the proper circumstances the use of dredged material for
beach nourishment not only contributes to the development and maintenance of
waterway transportation, but also provides hazard reduction and recreational
benefits consistent with environmental mandates and the material laws governing
coastal systems. Beach nourishment is the least-cost environmentally acceptable
disposal alternative. Despite its current prevalence, beach nourishment cannot be
considered a panacea for dredged material disposal ills. For three out of every
four navigation projects, the dredged material is not a practical, cost-effective,
and permissible source for beach nourishment supply. Most frequently, the
material is too fine-grained to be effective for shore protection. Other constraints
are excessive cost, unallowable environmental effects, and technical limitations.
3.1.4
Nature of "Beach Fill"
Material to be used, carefully selected as to nature and source site, may be
brought to the beach to be restored and dumped offshore, leaving it to the sea to
carry it to the shore and insuring its geographical distribution. It may also be
deposited at a single location on the beach; called stockpiling, it allows the
artificial supply point to act as a distribution center or feeder beach. Still another
approach is to spread directly the material on the endangered beach, restore it
stande pede and take simultaneously appropriate "soft" measures to protect it.
Finally the continuous supply method involves creation of a fixed, or semi-fixed
plant which first intercepts and then passes on the littoral drift to the down-drift
side.
In some cases a combined approach has been taken, e.g. offshore dumping and
on-shore nourishment. Beach nourishment has even been called upon to restore
lake beaches, for instance in the Province of Qu6bec (Lac St. Jean).
The beach nourishment approach has been also used on lakes shorelines ; this has
been the case at Lac St. Jean in Canada and on the shores of Lake Michigan, for
instance in Evanston, Fort Sheridan, Highland Park, Lake Bluff, Illinois Beach
State Park and at several beaches of Chicago (Illinois).
Sand nourishment of Chicago beaches between 1961 and 1964 involved
deposition of 381.000 m 3 (498.300 cu.yd).
While the technique is the same for lake and oceanic beaches there are some
environmental differences to be reckoned with.