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Sustaining Coastal Landforms
January 2001
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a PDF file.) 
Coastal landforms are valuable environmental, aesthetic, and recreational
resources that are subject to natural processes as well as the effects
of human activities. Beaches, dunes, barrier beaches, coastal banks,
saltmarshes and coastal floodplains are appreciated by the general
public and regulated by government agencies to ensure protection
of the bene-ficial functions of these landforms. Yet, in spite of
these efforts, coastal landforms are vulnerable to human alterations,
resulting in less stable landforms and lessening the value of these
resources for future generations.
For example, seawall or revetment construction on an eroding shore
may eliminate the fronting beach and alter the adjacent property.
Home construction in a dune field may alter the form of the dune,
eliminate stabilizing vegetation, and alter depositional patterns
of dune sands.

Revetment construction on an eroding coastal
bank in Eastham, MA, has resulted in the loss of the coastal beach
fronting the structure.
Photo by Jim O'Connell, WHOI Sea Grant
To counteract the negative effects of human activities
some communities are adopting procedures designed to re-establish
sustainability of coastal landforms damaged by previous activities.
Removing roads from barrier beaches or elevating structures in dune
fields are two such examples where dune growth and migration of
dune sands may be maintained.
Are activities on coastal landforms detracting from
or adding to the beneficial functions of these landforms on both
a short term and a long-term basis? To address this question WHOI
Sea Grant has undertaken a Coastal Landform System Sustainability
Project, focusing on the management of coastal landforms on Cape
Cod. The project began with a workshop held during October 1997,
"Coastal Landform Management in Massachusetts," that addressed
the science and management concerns of shoreline change and monitoring
changes in coastal landforms. The format of the workshop allowed
participants to assume the various roles of landowner, coastal resource
manager, commercial or recreational user, and public rights advocate
in an effort to negotiate an action that imposed a minimal impact
on the sustainability of the coastal landform.
A follow-up activity to the workshop was development
of the Coastal Landform System Sustainability Project with participation
by WHOI Sea Grant staff, the Cape Cod Commission and the local conservation
commissions in each Cape Cod town. The objectives of the project
were to:
1. Quantify, on a town-by-town basis, the gains and
losses of Cape Cod coastal landform system sustainability resulting
from decisions of local resource management and regulatory agencies;
2. Identify the state and local policies and/or regulations
(or lack thereof) that have resulted in these gains and losses;
3. Describe permit conditions and/or technical approaches
that may assist in maintaining coastal landform system sustainability;
and
4. Identify future research needs that will add to
our understanding of the interaction between coastal landform function
and human actions that may assist in optimum management of our coastal
landform systems.
To achieve the project goals, a questionnaire was
developed to provide the data necessary to estimate the gains and
losses of coastal landform sustainability. The conservation agent
for each town completed a questionnaire for each activity permitted
by the community's conservation commission. A ranking scheme was
developed to evaluate the degree of impact from an activity on a
coastal landform. In this project, 318 Orders of Conditions (permits)
issued during 1999 for activities on or adjacent to coastal landforms
by the participating 15 Cape Cod towns were analyzed. Collectively,
47 specific activities were permitted.
The results of the analysis are presented in the attached
Table 1. Positive ratings suggest the
coastal landform and the system in which it resides are being sustained
(i.e., the beneficial functions of the landforms are being protected
by the decisions). Conversely, negative ratings suggest that the
sustainability of the landform and its system are not being adequately
protected (i.e., the beneficial functions of the landforms are being
diminished by the collective decisions). Although positive ratings
exist within the data set presented in Table
1, cumulative negative ratings were summed for all coastal landforms.
What this suggests is that, collectively, the natural functioning
of certain coastal landform systems are not being sustained on Cape
Cod.
This project documents the types of activities presently
taking place on and adjacent to the coastal landforms on Cape Cod
and their potential effects, as well as potential mitigation being
required by local conservation commissions to minimize these effects.
It also documents the trade-offs and balances that may be necessary
in the application of performance standard-based regulations governing
activities proposed on coastal landforms. As our quantitative understanding
of coastal landform function is still evolving, particularly on
a small scale lot-by-lot basis, many decisions may be made using
best professional judgment without the predictive capability of
knowing what the impact will be on the applicant's or neighboring
property and resources.
Massachusetts regulations, policies, and bylaws governing
activities on coastal landforms are based on identification of their
critical characteristics to preserve certain public interests (e.g.,
storm damage prevention, flood control, preservation of wildlife
habitat). These standards are based on requiring the mobility of
coastal landforms. Yet, it appears that in a strict sense we are
not sustaining our coastal landforms. If we desire our decisions
to ultimately maximize or optimize coastal landform system sustainability
in the face of continuing development on and adjacent to these valuable
landforms, we must begin an intensive program to research and monitor
the impacts -- positive and negative -- of small scale activities
to help guide our future decisions.
It is hoped that the results of this Sea Grant study
will assist local, state, and federal coastal resource managers
and regulators, as well as the public, to gain insight into the
interactions of human activities and the natural functioning of
coastal landform systems leading towards improved coastal resource
management.
References:
Coastal Landform Management in Massachusetts: Proceedings
of a Workshop held at the Woods Hole Oceanographic Institution,
Woods Hole, MA, USA, October 9-;10, 1997. T.I. Crago and S.D. DeRosa
(eds.), WHOI Technical Report WHOI-98-16, 1998, 118 p.
Coastal Landform System Sustainability Project: An
Analysis of Activities Permitted on Coastal Landforms on Cape Cod,
MA, in 1999, J.F. O'Connell, WHOI Technical Report WHOI-2000-09,
2000, 56 p.
For more information about WHOI Sea Grant's Coastal
Landform Sustainability project, coastal processes, or any other
information included in this Focal Point, please contact the WHOI
Sea Grant Program at the address listed below.
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