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WAC 173-26-231 Shoreline modifications
WAC 173-26-231
Shoreline modifications
(1) Applicability. Local governments are encouraged to
prepare master program provisions that distinguish between shoreline
modifications and shoreline uses. Shoreline modifications are generally
related to construction of a physical element such as a dike, breakwater,
dredged basin, or fill, but they can include other actions such as
clearing, grading, application of chemicals, or significant vegetation
removal. Shoreline modifications usually are undertaken in support of or
in preparation for a shoreline use; for example, fill (shoreline
modification) required for a cargo terminal (industrial use) or dredging
(shoreline modification) to allow for a marina (boating facility use).
The provisions in this section apply to all shoreline modifications
within shoreline jurisdiction.
(2) General principles
applicable to all shoreline modifications. Master programs shall
implement the following principles:
(a) Allow structural shoreline modifications only where they are
demonstrated to be necessary to support or protect an allowed primary
structure or a legally existing shoreline use that is in danger of loss or
substantial damage or are necessary for reconfiguration of the shoreline
for mitigation or enhancement purposes.
(b) Reduce the adverse effects of shoreline modifications and, as
much as possible, limit shoreline modifications in number and extent.
(c) Allow only shoreline modifications that are appropriate to the
specific type of shoreline and environmental conditions for which they are
proposed.
(d) Assure that shoreline modifications individually and cumulatively
do not result in a net loss of ecological functions. This is to be
achieved by giving preference to those types of shoreline modifications
that have a lesser impact on ecological functions and requiring mitigation
of identified impacts resulting from shoreline modifications.
(e) Where applicable, base provisions on scientific and technical
information and a comprehensive analysis of drift cells for marine waters
or reach conditions for river and stream systems. Contact the department
for available drift cell characterizations.
(f) Plan for the enhancement of impaired ecological functions where
feasible and appropriate while accommodating permitted uses. As shoreline
modifications occur, incorporate all feasible measures to protect
ecological shoreline functions and ecosystem-wide processes.
(g) Avoid and reduce significant ecological impacts according to the
mitigation sequence in WAC
173-26-201 (2)(e).
(3) Provisions for specific shoreline modifications.
(a) Shoreline stabilization.
(i) Applicability. Shoreline stabilization includes actions
taken to address erosion impacts to property and dwellings, businesses, or
structures caused by natural processes, such as current, flood, tides,
wind, or wave action. These actions include structural and nonstructural
methods.
Nonstructural methods include building setbacks, relocation of the
structure to be protected, ground water management, planning and
regulatory measures to avoid the need for structural stabilization.
(ii) Principles. Shorelines are
by nature unstable, although in varying degrees. Erosion and accretion are
natural processes that provide ecological functions and thereby contribute
to sustaining the natural resource and ecology of the shoreline. Human use
of the shoreline has typically led to hardening of the shoreline for
various reasons including reduction of erosion or providing useful space
at the shore or providing access to docks and piers. The impacts of
hardening any one property may be minimal but cumulatively the impact of
this shoreline modification is significant.
Shoreline hardening typically results in adverse impacts to shoreline
ecological functions such as:
- Beach starvation. Sediment supply to nearby beaches is cut off,
leading to "starvation" of the beaches for the gravel, sand, and other
fine-grained materials that typically constitute a beach.
- Habitat degradation. Vegetation that shades the upper beach or bank
is eliminated, thus degrading the value of the shoreline for many
ecological functions, including spawning habitat for salmonids and forage
fish.
- Sediment impoundment. As a result of shoreline hardening, the
sources of sediment on beaches (eroding "feeder" bluffs) are progressively
lost and longshore transport is diminished. This leads to lowering of
down-drift beaches, the narrowing of the high tide beach, and the
coarsening of beach sediment. As beaches become more coarse, less prey for
juvenile fish is produced. Sediment starvation may lead to accelerated
erosion in down-drift areas.
- Exacerbation of erosion. The hard face of shoreline armoring,
particularly concrete bulkheads, reflects wave energy back onto the beach,
exacerbating erosion.
- Ground water impacts. Erosion control structures often raise the
water table on the landward side, which leads to higher pore pressures in
the beach itself. In some cases, this may lead to accelerated erosion of
sand-sized material from the beach.
- Hydraulic impacts. Shoreline armoring generally increases the
reflectivity of the shoreline and redirects wave energy back onto the
beach. This leads to scouring and lowering of the beach, to coarsening of
the beach, and to ultimate failure of the structure.
- Loss of shoreline vegetation. Vegetation provides important
"softer" erosion control functions. Vegetation is also critical in
maintaining ecological functions.
- Loss of large woody debris. Changed hydraulic regimes and the loss
of the high tide beach, along with the prevention of natural erosion of
vegetated shorelines, lead to the loss of beached organic material. This
material can increase biological diversity, can serve as a stabilizing
influence on natural shorelines, and is habitat for many aquatic-based
organisms, which are, in turn, important prey for larger organisms.
- Restriction of channel movement and creation of side channels.
Hardened shorelines along rivers slow the movement of channels, which, in
turn, prevents the input of larger woody debris, gravels for spawning, and
the creation of side channels important for juvenile salmon rearing, and
can result in increased floods and scour.
Additionally, hard structures, especially vertical walls, often
create conditions that lead to failure of the structure. In time, the
substrate of the beach coarsens and scours down to bedrock or a hard clay.
The footings of bulkheads are exposed, leading to undermining and failure.
This process is exacerbated when the original cause of the erosion and
"need" for the bulkhead was from upland water drainage problems. Failed
bulkheads and walls adversely impact beach aesthetics, may be a safety or
navigational hazard, and may adversely impact shoreline ecological
functions.
"Hard" structural stabilization
measures refer to those with solid, hard surfaces, such as concrete
bulkheads, while "soft" structural measures rely on less rigid materials,
such as biotechnical vegetation measures or beach enhancement. There is a
range of measures varying from soft to hard that include:
- Vegetation enhancement;
- Upland drainage control;
- Biotechnical measures;
- Beach enhancement;
- Anchor trees;
- Gravel placement;
- Rock revetments;
- Gabions;
- Concrete groins;
- Retaining walls and bluff walls;
- Bulkheads; and
- Seawalls.
Generally, the harder the construction measure, the greater the
impact on shoreline processes, including sediment transport,
geomorphology, and biological functions.
Structural shoreline stabilization often results in vegetation
removal and damage to near-shore habitat and shoreline corridors.
Therefore, master program shoreline stabilization provisions shall also be
consistent with WAC
173-26-221(5), vegetation conservation, and where applicable, WAC
173-26-221(2), critical areas.
In order to implement RCW
90.58.100(6) and avoid or mitigate
adverse impacts to shoreline ecological functions where shoreline
alterations are necessary to protect single-family residences and
principal appurtenant structures in danger from active shoreline erosion,
master programs should include standards setting forth the circumstances
under which alteration of the shoreline is permitted, and for the design
and type of protective measures and devices.
(iii) Standards. In order to
avoid the individual and cumulative net loss of ecological functions
attributable to shoreline stabilization, master programs shall implement
the above principles and apply the following standards:
(A) New development should be
located and designed to avoid the need for future shoreline stabilization
to the extent feasible. Subdivision of land must be regulated to assure
that the lots created will not require shoreline stabilization in order
for reasonable development to occur using geotechnical analysis of the
site and shoreline characteristics. New development on steep slopes or
bluffs shall be set back sufficiently to ensure that shoreline
stabilization is unlikely to be necessary during the life of the
structure, as demonstrated by a geotechnical analysis. New development
that would require shoreline stabilization which causes significant
impacts to adjacent or down-current properties and shoreline areas should
not be allowed.
(B) New structural stabilization
measures shall not be allowed except when necessity is demonstrated in the
following manner:
(I) To protect existing primary structures:
- New or enlarged structural shoreline stabilization measures for an
existing primary structure, including residences, should not be allowed
unless there is conclusive evidence, documented by a geotechnical
analysis, that the structure is in danger from shoreline erosion caused by
tidal action, currents, or waves. Normal sloughing, erosion of steep
bluffs, or shoreline erosion itself, without a scientific or geotechnical
analysis, is not demonstration of need. The geotechnical analysis should
evaluate on-site drainage issues and address drainage problems away from
the shoreline edge before considering structural shoreline stabilization.
The erosion control structure will not result in a net loss of
shoreline ecological functions.
(II) In support of new nonwater-dependent development, including
single-family residences, when all of the conditions below apply:
- The erosion is not being caused by upland conditions, such as the
loss of vegetation and drainage.
- Nonstructural measures, such as placing the development further
from the shoreline, planting vegetation, or installing on-site drainage
improvements, are not feasible or not sufficient.
- The need to protect primary structures from damage due to erosion
is demonstrated through a geotechnical report. The damage must be caused
by natural processes, such as tidal action, currents, and waves.
The erosion control structure will not result in a net loss of
shoreline ecological functions.
(III) In support of water-dependent development when all of the
conditions below apply:
- The erosion is not being caused by upland conditions, such as the
loss of vegetation and drainage.
- Nonstructural measures, planting vegetation, or installing on-site
drainage improvements, are not feasible or not sufficient.
- The need to protect primary structures from damage due to erosion
is demonstrated through a geotechnical report.
- The erosion control structure will not result in a net loss of
shoreline ecological functions.
(IV) To protect projects for the restoration of ecological functions
or hazardous substance remediation projects pursuant to chapter
70.105D RCW when all of the conditions below apply:
- Nonstructural measures, planting vegetation, or installing on-site
drainage improvements, are not feasible or not sufficient.
- The erosion control structure will not result in a net loss of
shoreline ecological functions.
(C) An existing shoreline stabilization structure may be
replaced with a similar structure if there
is a demonstrated need to protect principal uses or structures from
erosion caused by currents, tidal action, or waves.
- The replacement structure should be designed, located, sized, and
constructed to assure no net loss of ecological functions.
- Replacement walls or bulkheads shall not encroach waterward of the
ordinary high-water mark or existing structure unless the residence was
occupied prior to January 1, 1992, and there are overriding safety or
environmental concerns. In such cases, the replacement structure shall
abut the existing shoreline stabilization structure.
- Where a net loss of ecological functions associated with critical
saltwater habitats would occur by leaving the existing structure, remove
it as part of the replacement measure.
- Soft shoreline stabilization measures that provide restoration of
shoreline ecological functions may be permitted waterward of the ordinary
high-water mark.
- For purposes of this section standards on shoreline stabilization
measures, "replacement" means the construction of a new structure to
perform a shoreline stabilization function of an existing structure which
can no longer adequately serve its purpose. Additions to or increases in
size of existing shoreline stabilization measures shall be considered new
structures.
(D) Geotechnical reports pursuant
to this section that address the need to prevent potential damage to a
primary structure shall address the necessity for shoreline stabilization
by estimating time frames and rates of erosion and report on the urgency
associated with the specific situation. As a general matter, hard armoring
solutions should not be authorized except when a report confirms that
there is a significant possibility that such a structure will be damaged
within three years as a result of shoreline erosion in the absence of such
hard armoring measures, or where waiting until the need is that immediate,
would foreclose the opportunity to use measures that avoid impacts on
ecological functions. Thus, where the geotechnical report confirms a need
to prevent potential damage to a primary structure, but the need is not as
immediate as the three years, that report may still be used to justify
more immediate authorization to protect against erosion using soft
measures.
(E) When any structural shoreline stabilization measures are
demonstrated to be necessary, pursuant to
above provisions.
- Limit the size of stabilization measures to the minimum necessary.
Use measures designed to assure no net loss of shoreline ecological
functions. Soft approaches shall be used unless demonstrated not to be
sufficient to protect primary structures, dwellings, and businesses.
- Ensure that publicly financed or subsidized shoreline erosion
control measures do not restrict appropriate public access to the
shoreline except where such access is determined to be infeasible because
of incompatible uses, safety, security, or harm to ecological functions.
See public access provisions; WAC
173-26-221(4). Where feasible, incorporate ecological restoration and
public access improvements into the project.
- Mitigate new erosion control measures, including replacement
structures, on feeder bluffs or other actions that affect beach
sediment-producing areas to avoid and, if that is not possible, to
minimize adverse impacts to sediment conveyance systems. Where sediment
conveyance systems cross jurisdictional boundaries, local governments
should coordinate shoreline management efforts. If beach erosion is
threatening existing development, local governments should adopt master
program provisions for a beach management district or other institutional
mechanism to provide comprehensive mitigation for the adverse impacts of
erosion control measures.
(F) For erosion or mass wasting due to upland conditions, see WAC
173-26-221 (2)(c)(ii).
(b) Piers and docks. New
piers and docks shall be allowed only for water-dependent uses or public
access. As used here, a dock associated with a single-family residence is
a water-dependent use provided that it is designed and intended as a
facility for access to watercraft and otherwise complies with the
provisions of this section. Pier and dock construction shall be restricted
to the minimum size necessary to meet the needs of the proposed
water-dependent use. Water-related and water-enjoyment uses may be allowed
as part of mixed-use development on over-water structures where they are
clearly auxiliary to and in support of water-dependent uses, provided the
minimum size requirement needed to meet the water-dependent use is not
violated.
New pier or dock construction, excluding docks accessory to
single-family residences, should be permitted only when the applicant has
demonstrated that a specific need exists to support the intended
water-dependent uses. If a port district or other public or commercial
entity involving water-dependent uses has performed a needs analysis or
comprehensive master plan projecting the future needs for pier or dock
space, and if the plan or analysis is approved by the local government and
consistent with these guidelines, it may serve as the necessary
justification for pier design, size, and construction. The intent of this
provision is to allow ports and other entities the flexibility necessary
to provide for existing and future water-dependent uses.
Where new piers or docks are allowed, master programs should contain
provisions to require new residential development of two or more dwellings
to provide joint use or community dock facilities, when feasible, rather
than allow individual docks for each residence.
Piers and docks, including those accessory to single-family
residences, shall be designed and constructed to avoid or, if that is not
possible, to minimize and mitigate the impacts to ecological functions,
critical areas resources such as eelgrass beds and fish habitats and
processes such as currents and littoral drift. See WAC
173-26-221 (2)(c)(iii) and (iv). Master programs should require that
structures be made of materials that have been approved by applicable
state agencies.
(c) Fill. Fills shall be located,
designed, and constructed to protect shoreline ecological functions and
ecosystem-wide processes, including channel migration.
Fills waterward of the ordinary high-water mark shall be allowed only
when necessary to support: Water-dependent use, public access, cleanup and
disposal of contaminated sediments as part of an interagency environmental
clean-up plan, disposal of dredged material considered suitable under, and
conducted in accordance with the dredged material management program of
the department of natural resources, expansion or alteration of
transportation facilities of statewide significance currently located on
the shoreline and then only upon a demonstration that alternatives to fill
are not feasible, mitigation action, environmental restoration, beach
nourishment or enhancement project. Fills waterward of the ordinary
high-water mark for any use except ecological restoration should require a
conditional use permit.
(d) Breakwaters, jetties, groins, and
weirs. Breakwaters, jetties, groins, and weirs located waterward of
the ordinary high-water mark shall be allowed only where necessary to
support water-dependent uses, public access, shoreline stabilization, or
other specific public purpose. Breakwaters, jetties, groins, weirs, and
similar structures should require a conditional use permit, except for
those structures installed to protect or restore ecological functions,
such as woody debris installed in streams. Breakwaters, jetties, groins,
and weirs shall be designed to protect critical areas and shall provide
for mitigation according to the sequence defined in WAC
173-26-201 (2)(e).
(e) Beach and dunes management.
Washington's beaches and their associated dunes lie along the Pacific
Ocean coast between Point Grenville and Cape Disappointment, and as
shorelines of statewide significance are mandated to be managed from a
statewide perspective by the act. Beaches and dunes within shoreline
jurisdiction shall be managed to conserve, protect, where appropriate
develop, and where appropriate restore the resources and benefits of
coastal beaches. Beaches and dunes should also be managed to reduce the
hazard to human life and property from natural or human-induced actions
associated with these areas.
Shoreline master programs in coastal marine areas shall provide for
diverse and appropriate use of beach and dune areas consistent with their
ecological, recreational, aesthetic, and economic values, and consistent
with the natural limitations of beaches, dunes, and dune vegetation for
development. Coastal master programs shall institute development setbacks
from the shoreline to prevent impacts to the natural, functional,
ecological, and aesthetic qualities of the dune.
"Dune modification" is the removal or addition of material to a dune,
the reforming or reconfiguration of a dune, or the removal or addition of
vegetation that will alter the dune's shape or sediment migration. Dune
modification may be proposed for a number of purposes, including
protection of property, flood and storm hazard reduction, erosion
prevention, and ecological restoration.
Coastal dune modification shall be allowed only consistent with state
and federal flood protection standards and when it will not result in a
net loss of shoreline ecological functions or significant adverse impacts
to other shoreline resources and values.
Dune modification to protect views of the water shall be allowed only
on properties subdivided and developed prior to the adoption of the master
program and where the view is completely obstructed for residences or
water-enjoyment uses and where it can be demonstrated that the dunes did
not obstruct views at the time of original occupancy, and then only in
conformance with the above provisions.
(f) Dredging and dredge material
disposal. Dredging and dredge material disposal shall be done in a
manner which avoids or minimizes significant ecological impacts and
impacts which cannot be avoided should be mitigated in a manner that
assures no net loss of shoreline ecological functions.
New development should be sited and designed to avoid or, if that is
not possible, to minimize the need for new and maintenance dredging.
Dredging for the purpose of establishing, expanding, or relocating or
reconfiguring navigation channels and basins should be allowed where
necessary for assuring safe and efficient accommodation of existing
navigational uses and then only when significant ecological impacts are
minimized and when mitigation is provided. Maintenance dredging of
established navigation channels and basins should be restricted to
maintaining previously dredged and/or existing authorized location, depth,
and width.
Dredging waterward of the ordinary high-water mark for the primary
purpose of obtaining fill material shall not be allowed, except when the
material is necessary for the restoration of ecological functions. When
allowed, the site where the fill is to be placed must be located waterward
of the ordinary high-water mark. The project must be either associated
with a MTCA or CERCLA habitat restoration project or, if approved through
a shoreline conditional use permit, any other significant habitat
enhancement project. Master programs should include provisions for uses of
suitable dredge material that benefit shoreline resources. Where
applicable, master programs should provide for the implementation of
adopted regional interagency dredge material management plans or watershed
management planning.
Disposal of dredge material on shorelands or wetlands within a
river's channel migration zone shall be discouraged. In the limited
instances where it is allowed, such disposal shall require a conditional
use permit. This provision is not intended to address discharge of dredge
material into the flowing current of the river or in deep water within the
channel where it does not substantially affect the geohydrologic character
of the channel migration zone.
(g) Shoreline habitat and natural systems
enhancement projects. Shoreline habitat and natural systems
enhancement projects include those activities proposed and conducted
specifically for the purpose of establishing, restoring, or enhancing
habitat for priority species in shorelines.
Master programs should include provisions fostering habitat and
natural system enhancement projects. Such projects may include shoreline
modification actions such as modification of vegetation, removal of
nonnative or invasive plants, shoreline stabilization, dredging, and
filling, provided that the primary purpose of such actions is clearly
restoration of the natural character and ecological functions of the
shoreline. Master program provisions should assure that the projects
address legitimate restoration needs and priorities and facilitate
implementation of the restoration plan developed pursuant to WAC
173-26-201 (2)(f).
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