(b) Integrity of Structure. Good. During its 40-year lifetime, the breakwater has 

 weathered numerous severe storms with little displacement of stone. Parts of the breakwater 

 may have experienced slight subsidence but there is no observable damage. No maintenance 

 has been performed. 



(8) Effect of Structure on Environment. 



(a) Physical. Since construction, the rate of volume cliange of the beach 

 material has greatly increased. There has been accretion of beach material within the 

 protected zone greater than the erosion which had occurred previously. Survey profiles 

 shown in Figures 39 and 40 indicate that the buildup of material (profiles 14, 15 and 16) 

 was provided from material eroded from the adjacent sections of the beach to the north and 

 south (profiles 10, 11, 12, 18 and 19). 



The erosion rate north of the breakwater increased after construction of the breakwater. 

 Material from the beach north of the breakwater moves southward to the beach abreast of 

 the breakwater but does not return to the north during periods of reversal in the direction 

 of wave approach (as it did before construction of the breakwater). 



At the south end of the breakwater, there has been a tendency for waves to work around 

 the breakwater, over the bar and to wash out the beach just opposite its southerly end as 

 shown in tlie beach profiles. 



From 1938 through the 1950's as part of various protection and improvement plans, 

 seawall modifications and rockfill groins were constructed and various quantities of sand 

 were placed between the groins along the beach. Two areas were filled: north of the 

 breakwater and at the south end of the beach behind the breakwater. The groins, built to 

 retard the rate of erosion in these areas, have had limited success. 



In 1971 more sand was brought in by truck and placed on the beach opposite the fuU 

 length of the breakwater from the seawall towards the ocean. During a coastal storm in 

 February 1972, a substantial amount was lost. 



Tlie structure is not a hazard to navigation, although small-craft operations have been 

 restricted by shoaUng near the breakwater. Recreational activities, bathing in particular, 

 have benefited. 



(b) Biota. In the absence of recorded data, oral reports indicate a general 

 increase in marine hfe and bird population near the breakwater. Kelp and other vegetation 

 have been noted on the stone at the structure toe. 



(c) Aesthetics. The townspeople requested the breakwater rather than a higher 

 seawall, for aesthetic reasons. No known aesthetic objections. 



(9) Engineering. District Waterways Engineer, Massachusetts Department of Public 

 Worlis, 100 Nashua Street, Boston, Massachusetts 02114. 



(10) Construction Contractors (built in three stages). 



(a) Stage 1, Merritt, Chapman and Scott Corporation, New York, New York 

 10001 (discontinued operations). 



72 



