Four conceptual design alternatives were developed and include configurations with a tidal channel to the north and south of the site. The advantages (benefits) and disadvantages of each of the four alternatives are listed in Table 2 of the Design Report. However, analysis of nearshore processes indicate that all of the concepts will require some extent of protective berms to maintain existing park benefits and ongoing maintenance. The first alternative (Figure 13 in the report), similar to the original concept has a tidal channel to the north of the site, but proposes to outlet the channel north of the existing boat launch. There are a number of benefits to this design alternative. Grain size distribution of the sediment in the north of the site indicates a lower energy regime with less annual transport and therefore less likelihood of the tidal channel filling with sediment. The boat launch would act as a groin and maintenance on the ramp could support maintenance of the spit seaward of the channel and parking lot. This configuration would likely reduce the potential for natural wood accumulation within the tidal channel. Access to the channel for maintenance could be done when boat ramp maintenance is completed to reduce costs. Potential negatives for this design alternative are that northern facing channels in the Whidbey Basin tend to become filled with sediment and potentially close off after time. This channel configuration may lead to scour at the base of the bluff. The turn around and parking area would likely lose space in this configuration and require additional fill to prevent frequent flooding. The access road would need to be elevated, including a bridge over the stream crossing. Two pedestrian bridges would also be required. The perennial marsh would still be disconnected from tidal influence in this alternative. The other three alternatives evaluated a channel to the south with varying degrees of inundation of the park. All three of these alternatives take advantage of the low-lying marsh on the south side of the park which already experiences regular flooding from storm surge overwash of the barrier beach. The narrowest portion of the barrier beach is on the south side of the park indicating this is a transport zone and accumulation rates are lower so material can move across the beach and not deposit on the beach or in the new tidal channel. A channel on the south side of the park is away from major infrastructure, such as the boat launch, parking, turnaround, and smaller restroom so the channel can be wider and allow for natural channel adjustment. A channel on the south end of the park might be able to connect perennial stream to the new salt marsh. The three alternatives for the south tidal channel are summarized as follows: A. Alternative 2A (Figure 14) provides a minimal tidal marsh (approximately 2.5 acres) which is confined by a protective berm to the south of the picnic shelter. This option would not require any additional infrastructure changes, but provides the smallest net ecological benefit. In addition, tidal currents will be lowest because of smallest tidal prism which will present challenges for maintaining an open tidal channel. B. Alternative 2B (Figure 15) provides a larger tidal marsh (approximately 4.4 acres) and flushing of the marsh on the east side of the road. This option can combine the changes to the road with a protective berm to reduce the potential for flooding of the road. While this option provides a larger net ecological benefit, the tidal currents may still be reduced as compared to Alternative 1 or 2c. C. Alternative 2C (Figure 16) maximizes the ecological benefits while decreasing the changes to the park infrastructure as compared to Alternative 1. The marsh area for this alternative is approximately 8 acres. The existing perennial marsh is closest to the shoreline in the south of the site and may be able to connect to tidal channel in this configuration. The existing spit is narrowest at this location, indicating sediment accumulation rates are lower, so the channel may stay open for longer periods without maintenance. This configuration would place the channel farthest away from existing infrastructure, thus less impact to existing recreation at the site. There are some potential design constraints with this alternative, including the need for creating a sharp turn in the channel to avoid the roadway while connecting the channel to Puget Sound. Also, southerly facing channels allow for wood and other debris to enter estuary and accumulate as can be seen in reference sites (Figures 4 to 7). Our analysis showed that of the four alternatives developed, alternative 2C has the highest likelihood of maintaining a tidal channel opening through natural processes, but it would still require a significant amount of construction of new infrastructure to minimize potential flooding. While the report highlights this alternative for the conceptual design, SRSC is recommending WA State Parks consider an in-depth analysis if SLR impacts to the future viability of the Park before proceeding with a restoration alternative that makes public investment where those investments would be at risk and on going maintenance of any action will be required. This project would have benefitted Chinook, coho, chum and pink salmon, along with steelhead.