Date:   October 11, 2023

To:       Doug Sherrod 

             President, Silver Beach Association Board of Directors

From: Sean Davy

            Chair, East Brander Tidal Wetland Subcommittee

Re:       Summary of Subcommittee activities, findings and recommendations

cc.        EBTW Subcommittee members: Pete Dandridge, Lynn King, Suzanne Sarka, Steve Koller, Martin Malinow, Karin Lissakers, Melinda Sultan

Subsequent to the SBA Annual meeting in 2022, I was asked to Chair a subcommittee to investigate the health of the East Brander Tidal Wetland (“EBTW”) and to determine if any remedial action was warranted.  Further below is a bullet point summary of the subcommittee activities, findings and recommendations.  

Background: One of the SBA’s properties is the 0.75-acre tidal wetland, the “East Brander Tidal Wetland” (EBTW) located along the west shore of West Neck Harbor on the east side of East Brander Parkway. To the south of the pond is the lawn of a private residential property. To the east is a small narrow beach, a living shoreline, which separates most of the pond from West Neck Harbor. To the north of the pond is a private residential property separated from the wetland by a wooden bulkhead. A narrow ditch approximately mid-way along the pond's eastern shore extends to West Neck Harbor. The SBA owns 0.53 acres of the property and the neighbor on the south side owns 0.23 acres.

The EBTW is in the Central Zone of the Peconic Bay Estuary System and, like other wetlands in the system, has suffered from the encroachment of development, hardened shorelines, pollution from non-point sources, and climate change.

The developer’s plot from the 1920’s shows a viable channel from the wetland into West Neck Harbor that would have allowed tidal recharging; however, over time, that opening has accreted significantly such that regular flushing occurs only during extreme tidal conditions such as northeasters with their accompanying and strong winds, and, only then, through a minimal ditch subjected to incremental infilling.

Over the last forty years, the SBA has been documenting residents’ reports of possible algal blooms, mosquito hatches, and odors emanating from the wetland that are potentially secondary evidence for non-point source pollution.

In response to residents’ concerns and in an effort to maintain the EBTW as a vital and healthy ecosystem, the SBA has made periodic efforts to address these concerns.

·        1990: The SBA worked with Shelter Island Town officials and Suffolk County Vector Control to reopen/repair the channel to West Neck Harbor.

·        1993: With DEC approval, a backhoe was used to reopen the channel.

·        1998: DEC permit issued which was valid through 2003 to reopen the channel. The SBA was unable to procure the funding necessary to carry out dredging and remediation of the dredging materials.

·        2008: Costello Marine Contracting was asked to bid on permitting and dredging the channel. The $8,000 estimate was beyond the capacity of the SBA.

·        2010: To remediate runoff and flooding into the wetland from the surrounding properties and from East Brander Parkway, the SBA lobbied the Town of Shelter Island to contract Cashin Associates, Inc to conduct a field investigation of the wetland. Their report identified associated wetland plants and marine animals, documented salinity and water temperature, and identified the site as a “Coastal Salt Pond” with a S1S2 NYSDEC Natural Heritage rarity ranking. Cashin further characterized the EBTW as a “healthy ecosystem”.

·        2011: SBA personally undertook the goal of permitting from the DEC; however, the financial commitment for the now required survey and Environmental Impact Study were prohibitive.

·        2013: Town of Shelter Island installed catch/storm basins along the border between East Brander Parkway and the berm on the east side of the wetland to help offset potential non-point source pollution of the wetland.

Subcommittee activities:

·       Members met with Alexa Fournier, Restoration Planning and Policy Manager at NYS Department of Environmental Conservation, Brookhaven, to review the wetland. She and her colleague surveyed the site and described the EBTW as reasonably healthy. They identified an assortment of grasses and vegetation indicative of a saltwater environment and active but not thriving shellfish and crustacean life. The DEC expressed that dredging would help conditions but likely require significant maintenance.  They also felt that a bubbler could help increase dissolved oxygen content in the water reducing potential mosquito hatches and possible algal blooms and associated odors.

·       Site visit with Stephen Schott, Marine Botany/Habitat Restoration Specialist from Cornell University, whose observations were largely consistent with those of the DEC.

·       Frequent visits to the EBTW to gauge the degree of tidal flow. It was clear that the ETBW does get irregular salt water exchange during extreme high tides and during storms, especially when accompanied by wind that increases tidal surge.  The topography of the beach is such that the wetland sits somewhat lower than the beach and, consequently, during the more typical tidal flows of the summer months, water exchange is less likely, resulting in the increased water temperatures and decreased levels of oxygen levels more typically associated with deteriorating water conditions.

·       A lot survey was conducted by Peconic Surveyors and privately funded to confirm and mark the boundary lines to the property. An updated survey is required for any application to the DEC to do any remedial work of any sort on the EBTW.

·       As suggested by Steve Schott from Cornell, an application to the Peconic Estuary Partnership mini-grant program for a $25k grant to test and dredge a channel for the EBTW, as well as install a bubbler to increase dissolved oxygen.  Such application was later denied.

·       Investigation of the efforts by the Menantic Creek Keepers. Menantic Keepers decided to track temperature and dissolved oxygen levels within the creek given their similar concerns that the creek that is not thriving as it once did.  The Menantic group has raised private funds to install monitoring equipment (approx. $3k per unit) that automatically records these measurements. The maintenance of this equipment is substantial and has required a group of individuals to clean and download data weekly.

·       A request was made to the DEC to do one-off tests of the EBTW to determine if fecal coliform is present.  The EBTW was tested in mid-August and mid-September and results were a Fecal Coliform Bacteria level with an MPN (most probable number) of 2.9 FC/100mL and 3.6 FC/100mL respectively. For context, the drinking water standard is less than 1 colony of Total Coliform Bacteria/ 100 ml and swimming water must not exceed 200 bacterial colonies/100mL.  Accordingly, the readings reflect negligible contamination.  

·       Purchase of an inexpensive dissolved oxygen and temperature gauge to manually check the EBTW.  

o   A reading was taken on September 8th at 2pm during low tide with an air temp of 82 degrees. The dissolved oxygen was 3.5 mg/l at the edge of the EBTW in very shallow water and the temp of the water was 86 degrees.  The EBTW clearly had not had a good tidal exchange in a good while as the channel from the beach was extremely dry.  This reading seems to be exemplary of the extreme conditions experienced in late summer.  One would expect the reading of the interior of the EBTW to be somewhat higher.  

o   A second reading was taken on September 29th at 9am (mid-tide).  The EBTW was getting slow trickle from the tide at the time and had clearly received some tidal exchange in the intervening weeks.  The water level was a few inches higher generally.  The dissolved oxygen reading at the same spot was 6.3 mg/l with a water temperature of 62 degrees and an air temperature of 60 degrees. 

** Please see attached information with respect to dissolved oxygen levels. Generally, a reading below 3 suggests a challenging environment for sustaining sea-life.

Recommendations: If there were no budget constraints to our effort, it may be worthwhile to dredge a channel to increase tidal exchange to the EBTW.  It was in that spirit that we applied for a PEP mini-grant.  We know, however, that any such dredging would only prove temporary and a channel would have to be continually maintained.  In essence, we would be fighting nature.  In reality, we do have budget constraints and our observations indicate that the EBTW does in fact get some periodic tidal exchange.  That fact together with the dissolved oxygen and fecal coliform testing that raised no significant red flags, makes dredging less compelling.   Accordingly, our recommendations are as follows:

·       Dissolve the Subcommittee and revert future activities to the Board and volunteers informally.

·       Explore private funding for a bubbler to increase oxygenation and prevent an unhealthy drop in oxygen from lack of flow and higher temperatures.

·       Continue regular observations of the tidal flow to track the ongoing health of the EBTW.

·       Periodically test dissolved oxygen and temperature during the course of 2024 to better understand the seasonal variations.   Given the small size of the EBTW, we do not feel that expensive and time-consuming testing is warranted as is being undertaken by the Menantic Keepers.

·       Make the health and observations of the condition of our wetlands a regular Board discussion