The beach under study,, located at the head of Quincy Bay is 

 partially protected against wave action during the dominant north- 

 east storms by islands and by extensive shoal areas in front of the 

 beacho Littoral currents are relatively weak in the study area. The 

 shore consists of a highway embankment located over former beach and 

 marsh areas. The seaward face of this embankment along most of the 

 length of the study area is protected by a low stepped concrete wall 

 which is in need of repair During storms accompanied by extreme 

 high tides s storm waves break over this wall flooding the highway and 

 adjacent low-lying residential areas „ Fronting the seawall is a 

 narrow public beach which is mostly under water at high tide. The 

 lowering of this beach by erosion has exposed the toe of the seawall 

 to incipient undermining at a number of points,, The water is now 

 polluted by raw sewage discharged into Boston Harbor * However, 

 sewage treatment plants now under construction or proposed, will 

 materially reduce and probably ultimately eliminate the existing 

 pollution o In spite of the present undesirable characteristics of 

 the existing beach, it is now used extensively as a recreational 

 bathing beacho 



The division engineer recommended the construction of a concrete 

 encased steel sheet pile bulkhead immediately seaward of the existing 

 seawall throughout the greater portion of its length and the back- 

 fill of the space between the two structures to an elevation of +15 feet. 

 No provision was made for tie-backs, presumably because the sand fill 

 seaward of the bulkhead will also have an elevation of +15 feet or 

 3 feet below the top of that structure „ The Board nevertheless believed 

 that tie -backs should be included in the bulkhead design as a measure 

 of reasonable prudence and recommends that they be so included when 

 the detailed design of the structure is undertaken » 



The artificial sand fill proposed by the division engineer will 

 raise and widen the beach thereby constituting a material improvement 

 of the beach as a recreational facility., The Board was of the 

 opinion that this fill is also an essential part of the plan for the 

 protection of this shore and the installations immediately behind it„ 

 Without this protective fill the proposed bulkhead would be in- 

 adequate to withstand the direct attack of storm waves „ The alterna- 

 tive would be the construction of an expensive seawall with a 

 foundation level considerably below sea level and with adequate pro- 

 vision for protection at its toe„ Such a seawall would probably 

 hasten the present processes of erosion which would in turn result 

 in the ultimate loss of the existing beach with consequent increased 

 cost of maintenance of the wall itself „ 



The Beach Erosion Board noted that the recommended plan includes 

 two impermeable stone groins adjacent to the yacht club area The 

 stated purposes of these groins are to maintain a steeper beach slope 

 in the area between them, and prevent the movement of beach material 



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