approaches including the use of helicopters (e.g., McGehee and Mayers 2000)
and innovative intertidal deployment techniques have been adopted.
The measurement program had two objectives, the first being to investigate
coastal processes associated with waves, currents, and sediment transport in the
proposed project area. The approach was to obtain detailed field measurements
from the proposed project area suitable for estimating sand transport rates in the
surf zone and near a submerged jetty. The analysis of these measurements
provides information needed to test hypotheses concerning mechanisms for
southward sediment bypassing of the north jetty and on the relative importance
of cross-shore and longshore sediment transport on Ocean Shores Beach. The
second objective of the measurements was to provide information to verify wave,
current, and transport numerical models, thereby advancing their value as design
tools to aid in the optimization of project performance.
Overview
Data collection included deployment of (a) SonTek Hydra arrays to measure
waves, currents, and suspended sediment concentrations (SSC) in the intertidal
Profiler (ADP) and Hydra systems to measure waves, currents, and SSC in
deeper water. Description of the methods of deployment may also be found in
Osborne et al. (2002b).
Seven tripods equipped with ADP/Hydra systems were deployed near the
inlet entrance from September to November 1999 at approximately the same time
as five tripods deployed by the U.S. Geological Survey (USGS) on the ebb shoal
to the north and south of the inlet as part of its nearshore processes study in 1999.
These data have been described previously by Hericks and Simpson (2000) and
analyzed by Osborne, Hericks, and Kraus (2002a). Further analysis of the USGS
data set has been presented by Sherwood et al. (2001).
In winter and spring 2001, four Hydra systems were deployed and recovered
multiple times near the mean lower low water (mllw) shoreline along north beach
north of the north jetty. The systems are referred to hereafter as Surf and Inter-
tidal Dynamics Sensor Platforms (SIDSEP). At the same time, two ADP/Hydra
systems referred to hereafter as High-Energy Sub-Tidal Tripods (HESTT) were
deployed and recovered by an HH-60J helicopter in deeper water. In spring
2002, three additional HESTT (sta OS 7, OS 8, OS 9 as described in Chapter 4
of Volume I) were deployed by helicopter along North Beach and two Hydra
platforms were deployed by research vessel inside the entrance to Grays Harbor
at Damon Point (sta DP 1, DP 2). Figure D1 indicates the approximate
deployment locations for the SIDSEP (sta OS 1, OS 2, OS 3, OS 4), HESTT
(sta OS 5, OS 6, OS 7, OS 8, OS 9) and Damon Point platforms (sta DP 1, DP 2).
Table D1 indicates deployment/retrieval dates and time, location, and elevations.
The SIDSEP were located at elevations from +0.3 to -0.3 m (+1 to -1 ft)
mllw and from 80 to 140 m (262 to 460 ft) offshore of the mhhw contour (+9.4 ft
mllw). The position of sta OS 3 was shifted north in the spring deployment to
bring it in line with the USGS' Middle instrument transect). Station OS 5 was
located north of the submerged portion of the jetty approximately 610 m
(2,000 ft) offshore of the mhhw line at a bottom elevation of -5.5 m (-18 ft) mllw.
D2
Appendix D
Field Data Collection
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