HomeMy WebLinkAbout01282013 Coastal Management Plan Work Group Minutes
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MINUTES: Coastal Management Plan (CMP) Work Group – January 28th, 2013
PRESENT: Sarah Oktay, Carl Borchert, John Stover, Jamie Feeley, Emily MacKinnon, Kirk Riden and Bobby DeCosta
ALSO PRESENT: D. Anne Atherton, Pete Kaiser, 1-2 other public members
Meeting called to order at 5:05 pm
The agenda was approved with a motion by Carl and second by Emily
Sarah welcomed the newest CMPWG member Kirk and Julia Knisel of MA CZM.
The Committee read over the minutes from January 14th and decided to wait to vote on them until Bobby arrived and
could participate in discussion/vote.
Julia Knisel made a presentation to the Committee and public on the new shoreline change maps that have been
produced. MA Coastal Zone Management secured funding from NOAA to contract with the United States Geologic
Survey (USGS) to measure erosion and shoreline change along coastal MA. The collection of this data has revealed
certain trends such as the changes created from the armoring of coastal banks and erosion control projects which
decrease the amount of sediment contributed to the adjacent coastal system. CZM is hoping that these new maps will
help communities with questions regarding future development in coastal areas as well as retrofitting existing
development in coastal areas.
Julia explained how CZM measured the changes in shoreline position using reference points such as documented mean
high water or a visual indication (wet/dry line) from aerial photographs. The first delineations of historic shorelines in
MA were done in 1989 and the state has been continuing to measure the position of the shoreline with varying
consistency across the state. In 1997 they began to more accurately measure the rates of change and in 2001 created
the web browser for Shoreline Change in MA. 1994 had been the last delineated shoreline for Nantucket until now, 2009
shoreline data is available.
Nantucket has 86 miles of shoreline that has been delineated. This data will enable the Committee to take a closer and
more accurate, up to date look at the erosion or accretion trends of each Sector over the years. These trends can be
interpreted to give a clearer picture of how different management practices (structures) have impacted different areas
of the island. This should be done keeping in mind long and short term trends, storm events, seasonal changes to the
shoreline, etc.
Julia suggested that the Committee also continue to collect local knowledge and expertise on the history of Nantucket’s
shorelines. This may be very valuable to apply to project citing and permitting agency review of development proposals.
Julia also highlighted the fact that the statewide average erosion rate is approximately 0.5 ft/yr while Nantucket
experiences averages up to 10 times that in some areas. Nantucket has a must more natural setting than the majority of
the state with fewer structures and much more exposure. Julia also reminded the Committee to continue thinking about
sea level rise and the inundation maps available for planning purposes.
CZM has offered to create maps of specific areas to look at more closely, near Town infrastructure, etc. to further assist
the Committee.
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John commented that our draft Plan should definitely reference this data and include an appendix of the shoreline
change maps.
Sarah reminded everyone that the shoreline change maps represent the change in shoreline which does not necessarily
represent specific bank or dune erosion, rather it is representing beach erosion.
D. Anne asked if there was a methodology/process in place to assess cumulative impacts along a stretch of managed
shoreline. Julia responded that this is really only possible if monitoring is required when a project is constructed. Dave
suggested that specific transects could be examined to see long term changes to adjacent properties, but Julia
reinforced that the state’s data is not frequent enough to give a clear picture of how a specific structure impacts
adjacent properties. She also suggested that this would be a good reason to form a volunteer group to work on
collecting beach profiling data around the island. This has been done in previous years by the UMASS Field Station.
Pete added that beach profiling is only as valuable as the monitoring conditions are consistent. It always needs to be
done during similar conditions and without including extreme circumstances.
Bobby added that impacts of erosion control structures can only be implied so far away from the site. There are too
many variables to make direct association beyond neighboring properties unquestionable. Some impacts are more
obvious than others, such as the initiation of nourishment at Baxter Road causing the accretion of beach and dune at
Codfish Park.
Dave brought up the Cisco area and stated that when Hummock Pond was not opened for a period of 10 years the
erosion adjacent to the pond increased a lot. A significant amount of sand was always deposited adjacent to the cut as a
result of the openings.
John reiterated the importance of the Committee trying to document as many “stories” and “anecdotes” as possible
from local history.
Sarah raised the importance of trying to document the movement of the shoals around the island as well since they
have such a significant impact on the erosion of our shorelines.
Bobby and Pete both spoke of their own experience on the water out and around the shoals over the years and the very
apparent stability of the shoals. Their stability suggests the presence of more stable glacial deposits beneath the sand at
these locations. Bobby added that the Miacomet Ripp (point of breakers) is another area that has not experienced the
same erosion as areas immediately adjacent, suggesting a difference in sediment/stability.
John asked if the CMPWG should recommend further investigation of these shoals. Bobby emphasized the importance
of at least being aware of them and making sure that they are not lost or impacted by any coastal projects.
Sarah agreed that CMPWG could at least make a recommendation that more data/information be collected on the
offshore shoals, their substrate and how they affect erosion or accretion. She also suggested that several coastal geology
texts show soil maps of the island and offshore areas and that these may give some indication of general soil types in
these areas.
Bobby brought up the benefit to water quality in Sesachacha Pond from almost 20 years of openings. Sarah agreed but
stated that while Sesachacha is a naturally salty pond, Hummock and Miacomet Ponds maintain a freshwater
ecosystem/ecology that may not benefit from annual openings in the same way. Dave brought up the 10 year period
when Hummock Pond was not opened to the ocean and the increase of erosion adjacent to the pond along the south
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shore that seemed directly related. There was more discussion about the potential benefits or impacts from pond
openings. Emily added that Dr. Jim Sutherland has collected water samples from Hummock Pond pre and post opening
for the second year in a row and when he has finished analyzing the data he will be including it in a report to be released
in the coming weeks. Emily will make sure his findings are announced/shared.
Jamie Feeley suggested that since Bobby was now present they get back to reviewing the January 14th 2013 minutes.
Jamie stated that at the last meeting Bobby had introduced the idea of ranking specific erosion control structures within
each sector. This was accurately represented in the minutes. However he wanted to clarify the minutes to represent his
uneasiness with this idea. He had stated that he didn’t think such a ranking would necessarily be fair and would be too
subjective since many of these systems have never been used in specific areas of the island.
Bobby suggested that maybe for systems/methods that have not been used on the island it could be emphasized that
we have no data on this method and therefore the Committee can not make a recommendation on it.
John also reminded everyone that as times change the need/rank for certain systems will likely change.
Bobby agreed and suggested being more general, but stated that there are specific scenarios when specific methods
have been shown to be unfavorable or not appropriate such as beach nourishment on the cobble bottom habitat in
Sconset.
Jamie said that he just does not want to create a ranking system or structure for judging these methods in one area that
then has to be applied to other sectors where it is not as appropriate.
Bobby then suggested that the Committee could try to only focus on those methods that would be absolutely prohibited
from specific areas because of data that has already been collected.
Sarah suggested that as a way of being more general the Committee could link specific resources with specific methods
that should be avoided. The Committee will discuss this further as drafting of the Plan continues.
Jamie was satisfied that his concerns would be included in the January 28, 2013 meeting minutes and so, the January 14,
2013 minutes were unanimously approved with a motion from Bobby and a second from Jamie.
Bobby suggested using the next meeting to focus on completing the preliminary draft for Sector 2. The Committee
agreed with this idea. Sarah also stated that she will redistribute the minutes from December 10, 2012 when no quorum
was present so that the material can be discussed again and included in future minutes and drafting of the Plan.
The next meeting will be held Monday February 11, 2013 5-7pm with a location TBA.
Adjourned at 6:55 pm (with a motion from Bobby and a second from Carl).
Respectively submitted,
Emily MacKinnon