BEACH EROSION S TUDIES 
Beach erosion control studies of specific localities are usually made 
by the Corps of Engineers in cooperation with appropriate agencies of the 
various Stetes by authority of Section 2 of the River and Harbor Act approved 
3 July 1930. By executive ruling the costs of these studies are divided 
equally between the United States and the cooperating agencies. Information 
concerning the initiation of a ccoperative study may be obtained from any 
District or Division Engineer of the Corps of Engineers. After a report on 
a cooperative study has been transmitted to Congress, a summary thereof is 
included in the next issue of this bulletin. A summary of reports trans- 
mitted to Congress since the last issue of the Bulletin and a list of 
authorized cooperative studies follow: 
SUMMARIES OF REPORTS TRANSMITTED TO CONGRESS 
PLUM ISLAND, MASSACHUSETTS 
The area studied comprises the northerly .7 miles of the Atlantic 
Ocean shore of Plum Island within the limits of the City of Newburyport 
and Town of Newbury. The island extends southward from the mouth of the 
Merrimack River for a total length of about 8 miles. Its northern end is 
about 3.7 miles south of the Massachusetts-New Hampshire border. Develop- 
ment which includes a United States Coast Guard Station is concentrated in 
the northern 2 miles of the island. Other than the Coast Guard Station pro- 
perty, this shore frontage is almost entirely privately owned. The remainder 
of the island to the south, with minor exceptions, is a wild life sanctuary 
under Federal control. The population of the City of Newburyport and the 
Town of Newbury in 1950 were 14,111 and 1,94) respectively. 
Plum Island is a sandy barrier island with a narrow sand beach backed 
by dunes. It is separated from the mainland by Plum Island River and a wide 
marsh. The northern end of the island is split by a shallow body of water 
known as the Basin which projects southward from the Merrimack River 
estuary. The width of the island between the Basin and the Atlantic Ocean 
is about 350 feet at the narrowest part. The north end of the island at 
the Merrimack River has a width of about 0.6 mile. 
In recent years, the ocean shore line along the northern end of Plum 
Island has been subject to intermittent erosion and accretion, with shifting 
of the eroding area alongshore and a resulting gradual recession of the shore 
as a whole. Storm waves accompanying high tides pass over the beach berm 
and erode the dunes. Large volumes of material are removed in localized 
areas during severe storms. Shifting of the areas of erosion is associated 
with changes in the offshore bar. Eroding areas are incompletely restored 
due to a deficiency in the rate of supply of material to the area. The 
deficiency in supply is estimated at about 36,000 cubic yards annually. 
Adequate protection can be provided to the shore in the problem area by re- 
storing a suitable protective beach by artificial placement of sand fill. 
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