Port Townsend Ecosystem
- Salish Sea References
- Wiki Rules
The Port Townsend Ecosystem Site is a coastal watershed defined by a single beach drift cell. Sediments flow from south to north from a divergence at Fort Townsend State Park, to the convergence at Point Wilson, at Fort Warden State Park. Marina development on the Kai Tai Prairie barrier beach may interupt littoral drift, effectively creating two independant drift cells. Watershed drainage is concentrated to two significant historical barrier embayment sites, the Kah Tai Lagoon, and the Glen Cove Lagoon. A third embayment has been converted to the Point Hudson Marina.
Should the Port Townsend Watershed include the other side of the Pt. Wilson Convergence?
Notes on Workgroups and Efforts
- The most significant coastal management actions in this system appear to be the restoration of the barrier embayment at the mill site, and protection of the two largely intact sediment sources, and managing stormwater within the Pt. Townsend Community.
- This site makes me wonder about what we know about Enhancing habitat functions on urban shorelines, as there has been some experimentation on the Seattle Waterfront by Seattle Public Utilities
- Washington State Parks has been exploring modifying their water access site at Fort Townsend Park, with the potential to restore erosion and sediment inputs.
- Jefferson County has been finishing up their Shoreline Management Plan as required under the Shoreline Management Act.
- What is the status of the City of Port Townsend SMP?
- Is there potential for a Natural Resource Damage Assessment at Port Townsend Mill?
- What are the community groups active in this ecosystem site?
- The Northwest Maritime Center Dock completed in 2004 was designed to demonstrate low impact methods of dock construction combined with eelgrass restoration. Some monitoring was completed by Pacific Northwest National Laboratory Marine Science Lab.
- Adjacent to Kah Tai lagoon is the Kah Tai Prairie Preserve under managment.
Notes on Natural History
- Sand lance and surf smelt spawning have been observed with concentrations between Fort Townsend and the Mill, and in the crook below Fort Warden.
- Some sand lance spawning has been observed along the Port Townsand waterfront.
- No 'haulout sites' have been identified along this shoreline in the State Priority Species and Habitats database.
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.