Template:SPU 5027
From Salish Sea Wiki
Nearshore Strategies Data Report
Cereghino et al 2012 completed a soundwide analysis to identify and describe beach sites in Puget Sounds as part of a nearshore ecosystem restoration strategy (using remote sensing data c. 2000-2006). The following narrative was developed to support distribution and use of analysis results:
- Beach Site 5027 is a 14.07 km long beach system containing 7760 meters of barrier beach (55%) and 4 creek mouths, one of 30 beach sites located in the North Central Sub-basin. Based on these attributes it ranks 91 out of 100 in terms of size and complexity among all Puget Sound Beach systems. Over five generations of beach development, 28 percent of beach length now has some indicator of sediment supply degradation, and 56 percent of the nearshore zone has estimated impervious levels higher than 10 percent. Property boundaries now legally segment the shoreline with an average of one property every 91 meters. Based on these metrics, this site ranks 60 out of 100 in terms of estimated degradation among all beach sites in Puget Sound. The PSNERP Strategy Analysis places this site in Degradation Group D11, a group of 36 sites where parcel density and nearshore impervious levels indicates slightly above average levels of shoreline development but where sediment supply degradation is still very low. Based on this grouping we recommend this site for a restoration-based strategy, where there may be the opportunity through a combination of protection and restoration efforts to recover the full operation of ecosystem processes thereby recovering ecosystem services that are either degraded or at risk. The site faces a moderate risk from jetty development impounding sediment, has no impacts from active shoreline railroad, and faces a slight risk from predicted future population growth.
This site is among 518 littoral cells that contained barrier-type embayments. Historically this system contained 3 barrier-type embayments, with an embayment shoreline of 8.22 km, encompassing 58.4 hectares of tidal wetlands - considering the length of beach this is the equivelent of one embayment every 4 km. This system is one among 29 barrier embayment complexes in the North Central Sub-basin. Based on these metrics this site ranks 76 out of 100 in terms of size and complexity among all Puget Sound barrier embayment systems. The PSNERP Strategy Analysis placed this site in Potential Group P9, a large group of 69 sites with large embayments and wetlands at a typical density, identified as noteworthy sites for their high potential to provide ecosystem services.
Site 5027 currently has 1 embayment--2 less than under historical conditions. This has been accompanied by a 76 percent loss of wetland area and a 78 percent loss of embayment length, based on comparison to historic maps. None of the remaining embayment shoreline length has evidence of shoreline modification. Based on these metrics, and the general development status of the drift cell, the PSNERP Strategy Analysis ranked this system 60 out of 100 and placed this site in Degradation Group D2, a large group of 64 barrier embayment systems with extremely high loss of embayment shoreline length, perhaps indicating fill, but with moderate to low degradation across the drift cell and remaining embayments. Based on this grouping, the site is recommended for a restoration-based approach, where there may be the opportunity through a combination of protection and restoration efforts to recover the full operation of ecosystem processes thereby recovering ecosystem services that are either degraded or at risk.
