Marine Reaches
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Clallam County SMP Update - Inventory and Characterization Report 4. MARINE REACH INVENTORY This chapter describes the marine shoreline reaches that are within the jurisdiction of the County’s SMP (in WRIAs 18, 19, and a portion of 17, excluding incorporated areas and the Makah Reservation) (see Figure 3-7 for the reach locations). Reaches are described in terms of their physical attributes, ecological condition, and human environment / land use characteristics. Maps are provided in Appendix A. Based upon available County-wide data sources, key physical, ecological, and land use characteristics for each reach are detailed on “reach sheets,” located at the end of this section. A description of the available data sources, including data limitations, is presented in the “reach sheet explainer” following this chapter. The reach descriptions below contain a summary of the data presented within the reach sheets and additional pertinent information, including potential future land use impacts to shoreline processes and management issues and opportunities. 4.1 Reach 1: Diamond Point (Maps 1a to 6a in Appendix A) The “Diamond Point” reach contains 12.5 miles of marine shoreline, which extends along Miller Peninsula from the Clallam/Jefferson county line to the northwest corner of Sequim Bay (approximately one mile south of Travis Spit). The reach contains shoreline along Discovery Bay, the Strait of Juan de Fuca, and Sequim Bay. The reach also contains the mouth of Eagle Creek (Eagle Creek is not a shoreline of the state, except where it enters the Strait of Juan de Fuca). Jefferson County has designated the majority of the adjacent Discovery Bay shorelands as either Natural or Conservancy. The aquatic area is designated Priority Aquatic. These designations provide the highest levels of ecological protection available under the Jefferson County shoreline master program. 4.1.1 Summary of Baseline Conditions The predominant shoreform of Miller Peninsula is bluff backed beach. Over half of the shoreline consists of feeder bluffs, except for the Thompson Spit, Diamond Point, and Travis Spit vicinities. The feeder bluffs, combined with net shore-drift, supply the sands, gravels and cobbles that maintain barrier beaches at the spits and Diamond Point. A majority of the bluffs are considered to be unstable and some areas show evidence of recent slides—particularly on the shoreline west of Diamond Point. The shorelines along Diamond Point, Thompson Spit, Paradise Cove Spit, and Travis Spit are within a tsunami hazard zone and the FEMA coastal 100-year floodplain. Forage fish species such as surf smelt and sand lance spawn in the upper intertidal gravel and gravel-sand beaches of Discovery Bay and Sequim Bay (Figure 4-1). Eelgrass is mapped throughout a majority of the reach, and patches of kelp are mapped along the Strait. The marine shores in this area, and in particular the Discovery Bay and Sequim Bay shorelines, are prime habitat for juvenile salmonids, which use the shallow nearshore waters for migration and rearing. The Jamestown S’Klallam Tribe and Clallam County (2004) identified the nearshore areas between Sequim Bay on the east and Morse Creek on the west as being of particular importance ESA Page 4-1 March 2011 Clallam County SMP Update - Inventory and Characterization Report to Dungeness River salmon stocks. Lagoon/coastal embayment wetland habitat is present at Diamond Point, Thompson Spit, and Paradise Cove. Travis Spit and adjacent shorelines provides habitat for shorebirds and waterfowl, and contains a haulout area for marine mammals. Eagle Creek provides habitat for coho salmon and cutthroat trout. Most of the tidelands within the reach are publicly owned. Some public tidelands areas near Paradise Cove are leased for aquaculture, and some commercial geoduck beds are present throughout the reach, including the northeastern portion of Sequim Bay. Recreational shellfish harvesting is available on almost the entire north shore of Miller Peninsula, and south of Diamond Point on Discovery Bay. Discovery Bay was closed to shellfish harvesting in 2007 because of elevated fecal coliform levels, but has since reopened. The source of the bacteria is not known, but according to the WRIA 17 Watershed Management Plan several drains near Diamond Point carry pollution into Discovery Bay (Cascadia Consulting Group 2003). The reach has no other documented water quality impairments. Sections of the shoreline (6% of reach total) have been armored, presumably to protect adjacent residences. The armoring occurs along Diamond Point and Paradise Cove, which are accretion shoreforms. Approximately 3 docks are located in the Diamond Figure 4-1. Forage fish eggs on gravelly beach substrate Point vicinity, but no other overwater structures are present within the reach. Neither the docks nor the armoring occur along feeder bluffs or in transport zones. A few small segments of bulkhead occur in areas that support sand lance spawning and eelgrass. Page 4-2 ESA March 2011 Clallam County SMP Update - Inventory and Characterization Report Half of the shoreland area within the reach is heavily forested, which provides habitat for a diversity of wildlife species and helps stabilize erosive bluffs. Outside of the shoreland zone, the majority of Miller Peninsula upland area is forested. Land use along the shoreline is primarily undeveloped open space, with pockets of residential development. This is consistent with the zoning which is either R5 or open space. The densest concentration of residential development is located in the Diamond Point vicinity, with more sparse development in the Travis Spit vicinity and northeast Sequim Bay. The north, central portion of the reach is the undeveloped Miller Peninsula State Park, managed by Washington State Parks. More than half of the land in shoreline jurisdiction in this reach is publicly owned. A majority of the adjacent tidelands are also mapped as publicly owned. The uplands are accessible to the public; however, there are limited opportunities to access water from the uplands because of the presence of steep, unstable bluffs. Public shorelines in the northern portion of the reach can be accessed via a trail from Panorama Vista County Park. The shoreline along Discovery Bay can be accessed at one location, via an informal trail at within the site of the future Miller Peninsula State Park. 4.1.2 Future Land Use and Potential Effects on Shoreline Ecology There are a substantial number of undeveloped and underdeveloped parcels on this reach. Under current zoning regulations, approximately one-third of the shoreland area has potential for new residential development. The developable land is generally located along bluffs in the eastern and western portions of the reach, in areas that are mainly forested. Vacant parcels in the along Discovery Bay feeder bluffs are mostly 1- to 5-acre lots that cannot be subdivided under current zoning regulations. The lots are rectangular in size with narrow water frontages (approximately 150 feet). Development in these lots could result in relatively dense shoreline development as well as removal of forest cover near the erosive feeder bluffs in this area. Vegetation removal along bluffs tends to accelerate erosion, which can put adjacent homes and other structures at risk. The Washington State Parks Commission has put plans for development of Miller Peninsula State Park on hold due to budgetary constraints (WSP, 2011). The development would likely increase managed public access to the area, which would be a benefit to the community, but could lead to adverse effects on the quality of the nearshore environment if not properly designed and managed. Clearing, grading, impervious surface and shoreline modification could reduce the amount or quality of the forested habitat or create other adverse impacts on shoreline ecology. State park planners have mapped sensitive ecological features, opportunities and constraints for consideration in the initial planning stages. The residential land on Diamond Point has already been platted into small (approximately quarter-acre) parcels, and most of the homes are built within 50 feet of the ordinary high water line. Infill development on scattered vacant parcels could occur in the future. Few of the homes in this reach have a dock or other overwater structure since most of this reach is subjected to the strong wind and wave conditions that are prevalent along the Strait. There is some potential for new dock construction on the Discovery Bay shoreline since it is somewhat more protected ESA Page 4-3 March 2011 Clallam County SMP Update - Inventory and Characterization Report (from wind and waves), but the absence of docks along the Bay suggests that conditions are generally unsuitable for docks. Diamond Point landowners whose homes are close to the shore may seek to construct bulkheads or other shoreline armoring structures to protect their property from storm activity or changes in sea level, particularly on parcels bordering the Strait. An increase in armoring and/or overwater structures in the area may adversely impact sediment delivery and transport processes which could impact submerged aquatic vegetation communities and/or forage fish spawning habitat, which would in turn reduce the quality/suitability of this reach for salmonid rearing and migration. The nature and degree of the impact would depend on the type of armoring and its location relative to the ordinary high water line among other factors. There is a significant amount of undeveloped land in the Travis Spit vicinity, some of which are large parcels that may be subdivided into 5-acre lots under current zoning regulations. Similar to the southwestern portion of the reach, many parcels are rectangular in shape with water frontage widths averaging 150 feet. Potential shoreline impacts resulting from development on these parcels are similar to those described on the Discovery Bay shoreline. An area near Travis Spit is mapped as a waterfowl concentration area, and changes in the development density in this vicinity could reduce the quality or suitability of the habitat for waterfowl species.