As a resident of the town of Lavallette, I have been drawn in to numerous conversations (and speculation) concerning the contrast between what happened in the neighboring towns of Ortley Beach and Lavallette during Sandy. As a recap, Ortley beach got steamrolled, with many houses knocked off their foundations and/or obliterated by the storm, while a stone-throw away in Lavallette, most damage was limited to that by flooding, with only a few homes mechanically disturbed by the storm. So, why the stark difference in damage?
The explanation lies in the past, long before the full-tilt development of the barrier island took place. Ortley Beach, and some of the northern section of Seaside Heights, is the site of the old Cranberry Inlet, that used to connect central Barnegat Bay and the Atlantic Ocean, and is therefore a relatively level, low-lying area. This inlet was closed off in the early 1800’s by a series of storms that transported and deposited sand in its channels. There were a few natural and human attempts to reopen it many years ago, but all failed against nature’s will to keep it closed. A vegetated marsh developed in the area, which was eventually filled (but not significantly elevated) for development. Most of Lavallette, in contrast, lies on a relic dune system that lay to the north of Cranberry Inlet, much as the dunes of Island Beach State Park lie to the north of Barnegat Inlet today.
So, what does all this mean in the context of Sandy and other large-scale coastal storms? Well, first of all the roads in Ortley are relatively level from bay to beach, having been built on level-filled marshland. I am not sure how well these photos illustrate this point (it is fairly obvious when viewing these areas in person), but they are pictures of 6th Avenue in Ortley Beach and Philadelphia Avenue in Lavallette; one must walk uphill on most streets in Lavallette to get to the beach, while the same path in Ortley ranges from a slight incline to just about level.
Here are two Illustrations of what these areas generically look like in cross-section during normal conditions:
The following two illustrations depict what I can best interpret as having occurred during Sandy:
It is also extremely important to note that, while both towns possessed engineered dunes prior to Sandy, both towns lost their dunes during the storm (with exception of a select area on the north end of Lavallette which escaped relatively unscathed due to a higher elevation and a resilient dune). Walking the beaches of both towns shortly after Sandy, it was obvious that once the dunes in Ortley gave way, the surf had a straight-shot into the town, bowling over just about everything in its path; many homes were simply crushed and dismantled by the relentless wave action, and some of the better-built houses a few lots from the beach were carried and deposited on Route 35 North (!) when they were ripped off their foundations. In Lavallette, the rise of sand that once was the relic dune system appeared to survive (in most places partially, in some places fully), which was enough to dampen the wave action a bit, resulting in over-wash style waves rolling into the town vs. the full-force surf that steamrolled through Ortley.
A few realities are important to acknowledge here:
First, even with massive dunes slated to be built in both towns, low-lying areas such as Ortley Beach will remain relatively vulnerable to massive storm surge and surf in the future if their as-yet-to-be-constructed engineered dune system gives way as it did during this storm. That is not to say that dunes are futile or should not be built, but we need to engineer a substantial and functional dune and not just lump a small pile of sand, plant a little dune grass, and call it a day. We also must make sure we consider multiple lines of defense such as continued efforts to elevate homes, better protect infrastructure and utilities, and at least consider bulkheading or seawalls (acknowledging hard-armarment of shorelines is a controversial issue and can do more harm than good if engineered poorly, which I will likely address at a later time) under or behind the engineered dune line if we are steadfastly against abandoning/relocating barrier island communities.
Secondly, neither town will be safe from future storm surge events that fill the bay via the inlets, as I have previously discussed in this past entry.
Thirdly, had the storm surge and wave action been a few feet higher during Sandy, Lavallette (and other towns that fared similarly well due to similar profiles) may have suffered a similar fate as Ortley as there is most certainly an upper limit to how much water and force the relic dune system under the first few rows of ocean-block homes can handle; even though it fared well in this storm, it is surely not impervious to nature’s fury.
Finally, there is no one-size-fits-all solution to the issue of barrier island community vulnerability. While some basics apply to all (dunes generally good, low-lying areas exposed to waves bad, etc.), the same approach applied to all areas will not necessarily yield equal protection. Some additional analysis, creative thinking, and effort will be necessary to bring certain more-vulnerable areas up to equal resiliency.