Ediz Hook Phase 3 Beach Restoration And Nourishment: Intertidal Morphology Monitoring Summary

Shoreline morphology monitoring associated with a small-scale beach nourishment on Ediz Hook, near Port Angeles, Washington, suggests that there were persistent changes to shoreline morphology and beach grain size during the project period (April 2014 – July 2017). Changes were most dramatic and persistent within the nourishment area, but there was a measurable change in grain size to the west of the nourishment area that is attributable to alongshore transport of sediment1. The beach to east of the nourish area may have been influenced by alongshore transport of the nourish material, but these monitoring data are inconclusive, suggesting that the effect size is small. In the nourishment area the beach accretion was associated with a change in the median grain size of the middle intertidal (between Mean Low Water and Mean High Water) from ~50 mm to approximately ~10 mm. In the area to the west of the nourishment zone the median grain size of the middle intertidal dropped from ~15 mm to ~9 mm. Both observations suggest improved habitat quality for forage fish spawning.