Pleasure Beach - A Barrier Beach Earthcache
Welcome to Pleasure Beach this earthcache is located at a city park at one of my favorite shorelines! Please enjoy the views, take some notes and learn a little bit about this local beach and why it's essential for nearby local wetlands! Note that as this is an earthcache there is no container to be found at the posted coordinates. In order to log this cache as "found" you must send the cache owner answers to the logging requirements at the end of the description and in accordance with updated guidelines published on 10 JUN 19 you must post a photo of your visit with your submission log. Your answers are most easily sent via the message center feature. If you have any questions or concerns, please reach out to me!
NOTE: PLEASE DO NOT CLIMB THE SAND DUNES AS THEY ARE HIGHLY SUSCEPTIBLE TO DAMAGE. FOLLOW ALL POSTED SIGNS AND RESTRICTIONS.
Background
Pleasure Beach is both a public and private beach. The northern section of the beach originating at the end of Dock Road is a private beach. To access the beach from this parking lot you must be a member of a local beach association. Please use the posted parking and access points when going for this Earthcache. The southern portion of the beach is open to the public via the Waterford Parks Department. Additionally all water below the high tide line is public property and may be tranversed at will. A parking fee may apply. Pleasure Beach is located along Long Island Sound and on a clear day you can see Orient Point on Long Island!
A Beach in Constant Flux
Pleasure Beach, like all beach environments, exists in a constant state of flux and changes. The dynamic nature of the beach is due to both erosion and weathering as well as anthropological causes. Below are some recent examples of this dynamic nature:
- In 2012, tidal waves from Hurricane Sandy deposited large amounts of sand on top of the back dunes on the south side of the beach, and moved significant volumes of sand into the private parking lot at the end of Dock St.
- In the mid 1990s the Waterford Association artificially built up the local sand dunes to help protect the local wetlands (a process which will be discussed in further detail below).
- In the last decade, water currents have flattened the once steep "Kiddie Beach," creating expansive sand bars and new sand spits.
Img 1: Satellite photography showing the damage caused by Hurricane Sandy to Pleasure Beach
Despite it's changes, the beach remains critically important to protecting the wetlands behind the beach. These wetlands colloquially known as the "Clam Pond," are a critical habitat for migratory birds.
A Barrier Beach
Barrier Beaches are narrow and elongate beaches situated parallel to the shoreline. By definition, the beach provides a barrier between the mainland and adjacent nearshore wetland, such as a salt marsh or mudflat and marine waters offshore. Barrier beach systems are comprised of several distinctive topographic elements: the beach and dune complex, (which will be described in detailed below), tidal inlets, and wetlands such as mudflats or salt marsh. Classic barrier beaches occur along the length of the Atlantic Coastal Plain. Below you see the components of a barrier beach.
Img 2: Composition of a stereotypical Barrier Beach
In a natural barrier beach system the primary process of sediment distribution is longshore transport. In longshore transport, waves breaking on shore carry sand parallel to the coast helping to create the elongate form of the barrier beach. This phenomenon is exhibited in extensive beaches along the Atlantic coastal plain. Sediment transport in barrier beaches relies heavily on the morphology of the beach and what is referred to as "wave climate" which includes wave height and period (time between waves). These factors can vary seasonally or during storms. Due to its positioning in Long Isalnd sound, Pleasure Beach sees relatively little wave action compared to less sheltered beaches which open up directly onto the open ocean. As such the dunes here are comparatively small and take much longer to build.
Sand Dunes
Between the ocean and the wetlands you should be able to observe a sand dune. In its most simple terms a dune is a a hill made of sand. Beach dunes are critically important because they act as a reservoir of sand that nourishes the beach as sand naturally erodes away from storms, waves and wind. Additionally they protect the coastline from high-energy events such as hurricanes and tsunamis. They act as a breakwall to disperse energy and insultate the shoreline.
Coastal sand dunes formed during a time of low sea level where sand and sediments on the foreshore became exposed and in conjunction with sufficient winds, this sand was transported up the beach face via a geologic process known as saltation. Once sufficient wind mobilizes sand particles they become trapped in vegetation or drift wood at the back of the beach, sand then continues to accumulate among the vegetation and over time slowly builds up the dunes we see today.
Img 3: Saltation
Sand dunes serve an important purpose by protecting inland areas from coastal water intrusion. They are able to absorb the impact and protect inland areas from high energy storms and act as a resilient barrier to the destructive erosive forces of wind and waves. The below diagram shows the different parts of a typical beach dune.
Img 4: Composition of a Sand Dune
As a byproduct of being made of sand, dunes are particuarly susceptible to erosion. Local vegetation, particularly dune grass, is essential to anchoring the hill in place. As such you should only walk on marked paths as exploring the dunes could cause unnecessary erosion of this critical environment. On barrier beaches dunes seperate brackish and salt water. As storms erode away the foreshore (pictured above) sand from the backshore can move into the foreshore to replenish the beach. In certain cases of heavy storms (i.e. hurricanes) dunes are artificially replenished in an effort to protect sensitive coastlines and residential areas.
Logging Requirements
Please answer the following questions, to your best ability, using the information above and your observations at the posted coordinates. Any "Found It" logs that fail to submit the answers to the CO in a timely manner are subject to deletion. I will attempt to reach you to resolve any discrepancies prior to taking this course of action.
- In your owns words explain why sand dunes are important to preserving the shoreline.
- Estimate the height of the sand dune at GZ in relation to the high tide line on the beach. At high tide what level of storm surge could the dune withstand?
- What man-made structures have been erected at Pleasure Beach to prevent dune erosion during storms? Why do you think they are effective? Would a solid barrier be more effective?
- Post a photo of yourself or a recognizable personal item at Pleasure Beach!
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