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Source: https://erdc-library.erdc.dren.mil/jspui/ The literature on estimating extreme values of runup on beaches is reviewed. The few available models for estimating beach runup agree with each other and the available data. However, the models are of limited engineering usefulness. Also, the available data are significantly limited. The use of Hunt's Equation to scale beach run up should be carefully examined. Future research on beach run up is recommended and the importance of the engineering applications of such research is outlined. The extreme beach runup data set of R. A. Holman is published in Appendix B.

Source: https://erdc-library.erdc.dren.mil/jspui/ Methods for estimating the volume rate of wave overtopping by irregular seas are reviewed. Four methods are discussed in detail: Shore Protection Manual (SPM 1984), Goda (1971), Battjes (1974), and Owen (1980). Each method is discussed adequately for engineering use, and an example using each method is given. The assumptions made in each method's derivation and the importance of these assumptions are discussed also. Since the four methods were derived for different situations, the methods' ranges of applicability are summarized. The different methods yield results which can vary by more than an order-of-magnitude. For vertical seawalls, the SPM method estimates more overtopping than Goda's method except in very shallow water. For steeply sloped structures, the SPM method estimates less overtopping than Owen's method. For mildly sloped structures, the SPM method estimates less overtopping than Battjes' method except for very low relative freeboards. Published irregular-wave overtopping data are briefly reviewed and shown to be inadequate for evaluating the available methods. Until better data are available, estimates from these methods should be considered to be within a factor-of-three , and more conservatively, an order-of-magnitude of the actual overtopping rate.

Source: https://erdc-library.erdc.dren.mil/jspui/ Coastal response to navigation structures at Murrells Inlet, S. C., is documented herein. Data, which result from a postconstruction monitoring program, consist of beach, inlet, and jetty surveys, aerial photography, visual wave observations, wave buoy results, hindcast wave results, and site inspection trips. These data were collected during the period 1978-1982, approximately 5 years after jetty construction began. Beach change and wave data col.lected indicate that net longshore sand transport at the inlet has not been strongly to the south as previously assumed. The variability of longshore sand transport rate in time and space appears to be very important to coastal response to the jetties. Longshore transport rates are calculated from visual wave observations for 1979-1982. The direction of net transport was northward at all four wave data locations in 1979 and was toward the inlet from both sides during 1980-1982. The only wave data south of the inlet was close enough to be strongly affected by the jetties; therefore, a local reversal in net transport direction could have occurred south of the inlet during 1980-1982. Analysis of hindcast wave data for 1956-1975 indicates that the major southerly growth of the tip of Garden City in the early 1960's may have been in response to an unusually strong period of southerly sand transport. Possible modifications to the navigation project are suggested for further consideration and analysis. Improvements in the Murrells Inlet monitoring data collection program are recommended in light of the conclusions reached in this report.