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PUGET SOUND NEARSHORE ECOSYSTEM RESTORATION PROJECT (PSNERP)POTENTIAL RESTORATION AND PROTECTION PROJECTS
www.pugetsoundnearshore.org
Processes Restored
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Conditions Improved
RESTORATION AREA: 3-5 ACRES
• Restored coastal embayment that provides valuable nursery habitat for threatened species of juvenile salmon such as Chinook, increasing their survival and supporting population recovery in Puget Sound.
• Restored sand and gravel beaches that serve as spawning grounds for forage fi sh (e.g., surf smelt and Pacifi c sand lance), which are a key element of the marine food chain.
• Restored intertidal and shallow subtidal areas that are habitat for recreationally and culturally important shellfi sh such as oysters, mussels, and clams.
• Improved resiliency of the shoreline to respond to changes in the environment such as rising sea levels and increasing frequency of storm events.
• Improved public access to the shore and recreational opportunities.
• Movement of sand and gravel along shorelines.
• Natural erosion and accretion of beaches.
Twanoh State Park is located on the south side of Hood Canal near Union. Tidelands in this area support clams, oysters, and mussels as well as surf smelt spawning. The shellfi sh beds are an important recreational and Tribal resource. The development of this park dates back to the early 20th century and includes several historic park structures and view corridors. A notable feature is a saltwater wading pool created by enclosing a historic lagoon. More recent alterations include shoreline and streambank armoring to protect parking areas, a boat launch, and pile-supported dock. Construction of State Route 106 fi lled in some intertidal area on the west side of the park. The restoration project will improve the beaches and nearshore damaged by the fi ll and shore armor.
Twanoh State Park Beach Restoration
For more information, contact Curtis Tanner, Local Project Manager at [email protected] or (360) 902-2815
Key Design ElementsImage above depicts major project features. See design report for additional details.
www.pugetsoundnearshore.org
SO
UR
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: PS
NE
RP
(20
11);
US
DA
-NA
IP (
2009
)
The partial restoration alternative would be similar but with more limited removal of shoreline armor and fi ll. The boat ramp replacement and State Route 106 culvert replacement are not part of this alternative.
Both alternatives include gravel trails from the parking lots to the beach and creek mouth. Additional trails along the northern beach would lead visitors to the shoreline and provide access to picnic areas, the tide channel, and lagoon shore.
The full restoration alternative would remove armor along the shoreline and stream mouth, excavate fi lled areas, and remove pavement to recreate natural beaches. The saltwater pool would be restored to a natural tide channel and lagoon. To allow for natural sediment transport, the boat ramp would be replaced with a raised boat ramp. The culvert that conveys Twanoh Creek beneath State Route 106 would be replaced with a larger culvert or bridge. Installation of large wood and native plantings would further enhance shoreline habitat.
Replace Twanoh Creek culvert beneath Hwy 106 (F)
Replace boat rampwith raised boat ramp (F)
Hood CanalHood CanalHood Canal
Beach nourishment (F/P)
Excavate fill and regrade to natural beach profile (F/P)
Remove pavement (F/P) Restore tide channel and lagoon (F/P)
Remove rockarmoring (F/P)
Remove pavement (F/P)
Large wood placement (F/P)
106
N
=F/P Included in both Full & Partial Restoration
= Unique to Full RestorationF
= Unique to Partial RestorationP
Twanoh State Park Beach Restoration
