HIGH WATER IN COHASSET
Edward N. Wadsworth
Chair, Cohasset Central Cemetery Flood Mitigation Committee
Cohasset Central Cemetery is an ancient cemetery, its use dating back to the first decade of the 18th Century. It is a private cemetery listed on the National Register of Historic Places, a quite unusual credential for a cemetery and one that speaks to its very considerable historic merit. It consists of approximately 4.2 acres of gentle hillside and flatland assembled from several gifts of land at various times from municipal and private sources. It is an attractively landscaped cemetery and, besides playing a prominent role in the annual Cohasset Memorial Day festivities, is generally viewed as a valuable asset of Cohasset.
The most recent additions to the cemetery land occurred around the middle of the 19th century and includes land at the northern edge of the cemetery known as “Seaside”. As the name implies, Seaside borders water, namely Little Harbor, a significant tidal inlet not-with-standing the diminutive in its name.
It is Seaside where material flooding difficulties were identified. First, the coastal tide zone was simply very low, sufficiently so that some flooding occurred of areas inhabited by graves during the course of astronomical high tides (“King Tides”) and even during relatively minor storms. Second, for much of the flood prone area of the cemetery, the gradient was so very slight that virtually any flood waters would spread significantly inland.
The cemetery Board of Directors was not unmindful of an apparent increase in cemetery flooding, nor was it unmindful of the increasing public awareness and concern regarding Global Climate Change and its component, Sea Level Rise.
Beginning in early 2017, cemetery flooding became a regular reporting item at every Board meeting. And, influenced by photographs of the flooding effect of winter storms, the Board concluded both that the flooding was a cemetery problem that required addressing currently (i.e., not waiting for the impact of further Sea Level Rise) and that two director representatives should begin discussion with John Cavanaro, a highly regarded local engineer familiar with Little Harbor, as to possible ways to mitigate the flooding.
The discussion below will concentrate on the noteworthy elements of our flooding mitigation project existing primarily because cemeteries and graves are involved. Also, of course, the project lived by the overarching dictum that the integrity of the more than 100 individual graves in the impacted area would be scrupulously maintained at all times.
GRAVE SITE ELEVATION
Our deliberations strongly indicated, as engineering design features, that all new fill should be placed on top of the existing ground level and that all memorial material should be elevated to be on top of the new surface directly above where it had previously been located. Also, the selected design establishes a relatively solid basis which would be very helpful in the event that additional ground level elevation is required in the future.
The project design called for a 390 foot long stone retaining wall to be built just inland of the Little Harbor coastline, with approx. 26,000 square feet of cemetery land covered with new fill nestled behind the wall. Our Board had readily bought into the scientific conclusion that sea level height will continue to increase, but also that there is no way to be precise because of the unknown and currently unknowable variables. To assist us, we engaged the engineering consulting firm of Woods Hole Group of Bourne, Massachusetts which have developed a relevant expertise in the topic. Working with the Woods Hole Group and John Cavanaro, we fashioned a proposal which met the following criteria: it fit very well with the topography of the effected cemetery property; it remained within the financial goals we had established for the project and, with respect to Flood Mitigation: it met desirable flood mitigation targets (1) immediately following the completion of the project, and (2) during future years assuming the sea level continues to rise. Note that the target in (1) immediately above is the flooding that accompanied Winter Storm Riley, which seriously battered both Little Harbor and Cohasset Harbor in March of 2018. That is, the project, is designed so as initially to defeat flooding as great as that which occurred during Winter Storm Riley.
The Contracting Firm that we engaged, Iaria Bros. of Hingham, Massachusetts, proved to be a propitious selection because they carried out their responsibilities with creativity and diligence. The basic approach adopted was generally to proceed east to west making a single pass during which all of the construction of the new wall, the addition of the new fill and the resetting of all memorial materials occurred. In addition, some landscaping was accomplished although this could be accomplished at other times. After an area had been substantially completed, it was hydroseeded. Once the grass grew a bit, but for the handsome new stone wall along the edge of Little Harbor, the area was virtually indistinguishable from the same area prior to the project. Also, besides allowing for the quick recovery from the working area as an aesthetic matter, dealing with a relatively small number of memorials at a time made it far easier to insure that the memorials were reset accurately.
Matters involving cemeteries and graves, particularly when family members are involved, can be difficult. It is important to identify and respond to situations requiring special care and consideration. Also, whether to take the lead and publicly announce a project or whether to be reactive and respond to public disclosure by another party is a decision that should explicitly be made, and should depend on evaluation of a number of local features. For instance, if information disclosed by another party is materially incorrect, steps should almost surely be taken to correct the inaccuracies.