Aleutians West Coastal Resource Service Area, Volume II-Appendix C, Mitigation Opportunities in Unalaska June 2008

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1 Preservation of wetlands and associated riparian areas through land acquisition and other methods are potential mitigation projects. This category of mitigation includes: Purchase of land or conservation easements by a project applicant, Zoning restriction by a public entity; and Other non-regulatory mechanisms for habitat protection such as education & voluntary agreements Objectives: variable depending on the specific wetland development for which mitigation is required. An evaluation of the lacustrine and riverine wetland functions that are impacted and for which compensation will be required must be preformed. The feasibility of site preservation would vary considerably with the mechanism employed which varies with the level of protection afforded by the particular mechanism. In theory, the cost of land acquisition depends on the size of the site and the assessed value of the land. Figure 1. Wetlands at head of Unalaska Lake looking northwest. November 29, Figure 2. Wetlands at head of Unalaska Lake from Dutton Rd. May 12, C-12

2 Project 2. Wetland Preservation - Captains Bay/Shaishnikof River Goal: preservation of estuarine and riverine wetlands and other aquatic resources, including adjacent riparian areas. This area, particularly the estuarine area at the south end, is important for marine organisms. Preservation of wetlands and associated riparian areas through land acquisition and other methods as described above (project 1) are potential mitigation projects. Objectives: variable depending on the specific wetland development for which mitigation is required. An evaluation of the estuarine and riverine wetland functions that are impacted and for which compensation will be required must be preformed. The feasibility of site preservation would vary considerably with the mechanism employed which varies with the level of protection afforded by the particular mechanism. In theory, the cost of land acquisition depends on the size of the site and the assessed value of the land. Map 2. Captains Bay/Shaishnikof River Wetland Preservation location C-13

3 Figure 3. Shaishnikof River Wetland. May 13, Project 3. Wetland Preservation - South Channel Iliuliuk Harbor Goal: preservation of wetlands and other aquatic resources, including adjacent riparian areas. This area is important for marine organisms and is also an area of potential further development. A new bridge will be completed in The Little South America (LSA) Boat Harbor construction was expected to begin in 2008, but now may be delayed. Stellar Eider resting reefs will be constructed as mitigation for the LSA Boat Harbor. A large portion of the tidelands has been transferred to the City of Unalaska. Projects that restore and enhance functions that support subsistence salmon and crab, and preserve riparian areas through purchased conservation easements are a possibility in the area. Objectives: variable depending on the specific wetland development for which mitigation is required. An evaluation of the wetland functions that are impacted and for which compensation will be required must be preformed. Since the tidelands are zoned developable and the adjacent uplands are zoned marine dependent/industrial, the likely mechanisms are though zoning overlays. Figure 4. South Channel Iliuluk Harbor Wetland. May 13, C-14

4 Map 3. South Channel Iliuliuk Harbor Wetland Preservation location Project 4. Wetland Preservation Other Opportunities Goal: preservation of wetlands and other aquatic resources, including adjacent riparian areas. The AWCRSA Coastal Management Plan Volume 1 identifies many wetland areas suitable for preservation. These areas are depicted in red on the Coastal Resource Inventory Maps, Supplemental May 2003, Aleutians West-1 and Aleutians West-2. Areas suitable for wetland preservation include, but are not limited to, the head of Kashega Bay, the southwest arm of Makushin Bay, Broad Bay, Nateekin Bay, Summers Bay, Morris Cove, and Usof Bay. Objectives: variable depending on the specific wetland development for which mitigation is required. An evaluation of the wetland functions that are impacted and for which compensation will be required must be preformed. The feasibility of site preservation would vary considerably with the mechanism employed which varies with the level of protection afforded by the particular mechanism. Ownership and zoning is variable and thus the appropriate mechanism will vary. Project 5. Iliuliuk Lake Restoration Goal: restore and enhance lacustrine wetland functions that were lost by isolation from Unalaska Lake. C-15

5 Two sections of Unalaska Lake that where isolated by the development of Broadway Road are potential sites for mitigation. The larger section is known as Iliuliuk Lake. New culverts were installed in recent years improving both circulation and fish passage. However flooding was a significant problem during a 2007 storm event. This project would involve restoring and enhancing the wetland functions and values by correcting problems with water circulation, drainage and adding riparian cover. Figure 5. Iliuliuk Lake facing west from Dutton Road. November 29, Figure 6. Iliuliuk Lake facing west from Dutton Road. May 12, C-16

6 Objectives: increase water circulation, shoreline area and riparian cover; restrict access to portions of lake; remove trash and debris; preserve the site. Implementation of this project would require that access to the land surrounding the lake be obtained through an arrangement with the landowners or one of the formal land acquisition or other preservation mechanisms previously described. The type of acquisition or preservation mechanism will have significant impact on feasibility. Implementation would require coordination with the Army Corps of Engineers because it involves alteration of shorelines, placement of fill, and modification of drainage. Construction of this project would not require any special equipment, skills or expertise that is not locally available. Project 6. Iliuliuk River Restoration Goal: restore and enhance the riverine and riparian functions (fish spawning habitat, erosion control, flood retention, recreation/subsistence use) that have been lost over time by incremental development activity and heavy use. Figure 7 Upper Iliuliuk River. May 14, This project encompasses the length of the Illiuliuk River from the outlet of Unalaska Lake to its discharge into Iliuliuk Harbor, spanning a linear distance of approximately 3,000 feet. This is an important anadromous fish system in the Unalaska Bay area, and due to its location within the village of Unalaska is of high value for recreational and subsistence users (ADFG Anadromous Stream No ). C-17

7 Figure 8. Middle Iliuliuk River - erosion and trampling. May 14, Figure 9. Middle Iliuliuk River facing upstream. May 13, Stormwater run-off controls (paving, storm drain, oil separators) have been installed to help address problems with sedimentation, however many opportunities still exist. The project would involve restoring and enhancing the wetland and riparian functions of the site by correcting problems with shoreline trampling, erosion, and sedimentation. Public access that is designed to control and manage access points, such as a constructed trail or elevated boardwalk, could be incorporated into the project. Objectives: maintain and enhance traditional access while reducing impacts to shoreline associated with existing skiff docks; stabilize and revegetate the river banks and adjacent uplands; restore river substrates for pink salmon spawning; increase shallow water emergent vegetation. C-18

8 Figure 10. Lower Iliuliuk River facing downstream toward mouth. May 13, Depending on the access route that is selected, implementation of this project could require that access to the land along the riverbanks be obtained through an arrangement with the landowners or one of the formal land acquisition or other preservation mechanisms previously described. If access is provided along the base of Haystack Mountain, acquisition would not be necessary as the city of Unalaska owns the land. The type of acquisition or preservation mechanism will have significant impact on feasibility. Implementation would require coordination with the Army Corps of Engineers because it involves alteration of shorelines, placement of fill, and modification of drainage. Many examples of controlled public access with elevated walkways using low impact development techniques such as pin foundations exist in Alaska. The Kenai River Management Plan provides a good example. Project 7. Unalaska Lake Restoration Goal: restore and enhance functions that have been lost (spawning habitat for sockeye) over time due to sedimentation of the lake s littoral zones. C-19

9 Figure 11. Unalaska Lake Restoration. May 14, Sedimentation along the east shore and part of the south shore of Unalaska Lake has filled in areas previously used for spawning. The project would include a limiting factors analysis for sockeye salmon production within Unalaska Lake and then implementation of measures to address the limiting factors (e.g. sedimentation control and substrate enhancement). There is also an opportunity to develop a public access trail along one side of the lake where the City owns the land. Objectives: evaluate sockeye spawning and rearing habitat; evaluate feasibility of improving habitat, including removing sediments; public access trail development; implement a habitat enhancement plan. Because the City only owns the land on one side of the lake, implementation of this project would require that access to the land surrounding the lake be obtained through an arrangement with the landowners or one of the formal land acquisition or other preservation mechanisms previously described. The type of acquisition or preservation mechanism will have significant impact on feasibility. Implementation would require coordination with the Army Corps of Engineers because it involves alteration of shorelines, placement of fill, and modification of drainage. A formalized restoration and enhancement plan would be required. Project 8. Bird Habitat Enhancement/Lake Ilulaq Goal: enhance habitat values by creating habitat (bird nesting) that did not previously exist. Ilulaq Lake is a small lake on the hill above Biorka Drive on Amaknak Island. It has also been known as Chevron Lake and Water Supply Lake. There are no surface water outlets and thus it does not support anadromous fish. However it does provide lacustrine wetland functions of flood attenuation, erosion control and ground water recharge. The site has been identified as a possible location for bird habitat enhancement. C-20

10 Figure 12. Lake Ilulaq. May 12, Objectives: evaluate bird habitat; evaluate feasibility of improving habitat, including placement of nesting islets; implement a habitat enhancement plan. The riparian area is designated open space on the City Zoning maps. Implementation would require coordination with the Army Corps of Engineers because it could involve alteration of shorelines, and placement of fill. A habitat enhancement plan would need to consider reports of the need for bunker-c oil cleanup and WWII ordinance in the lake. Project 9. Kelp Nerocystis luetkeana, Alaria sp., and Laminaria sp. Bed Enhancement Goal: increase the functional value of certain marine intertidal sites by creating kelp beds that provide habitat for invertebrates, shellfish, finfish and other marine life. Many areas in the Unalaska Bay vicinity are suitable for Kelp bed enhancement. Three potential areas that were previously identified for deployment of artificial kelp substrates are Captains Bay, South Channel, and Dutch Harbor, but many others exist and may be more appropriate depending on the need for mitigation. This project would involve placement of artificial and rubble substrates at the appropriate depth for colonization by kelp (primarily Nerocystis luetkeana, Alaria sp., and Laminaria sp.). C-21

11 Objectives: identify appropriate sites for deployment of kelp substrates; design and construct kelp substrates; deploy substrates at appropriate sites. Implementation of this project is relatively simple. A formal project plan, including designs and cost estimates would be developed in consultation with resource agencies. The design of kelp substrates would be guided by evaluating substrates at a reference area located in a similar environmental setting. Implementation would require coordination with the Army Corps of Engineers because it involves placement of fill in navigable waters. Use of the tidelands would require permission from the landowner, for the most of Unalaska Bay this would be either the State of Alaska or the City of Unalaska. Construction of this project would not require any special equipment, skills or expertise that is not locally available. Artificial reef material, including quarry rock, is available locally. Figure 13. Kelp Beds. May 14, Project 10. Red King Crab Paralithodes camtschaticus Habitat Enhancement Goal: increase the functional value of certain marine nearshore sites by creating artificial reefs. The use of artificial reefs for enhancement of marine populations has received considerable attention in recent years (for examples see Jensen 2002). Such structures may be assembled from a variety of components including natural (logs and rocks), seminatural (concrete blocks, modules, or concreted boulders), and non-natural (tires, coal ash, wrecked ships, junked cars, and derelict oil platforms). Reefs have been constructed for a variety of recreational and C-22

12 commercial uses, including fisheries enhancement, scuba diving, aquaculture, habitat restoration, environmental mitigation, resource conservation, and research (Seaman 2002). Generally, production can be improved by use of highly complex structures that provide high levels of structural heterogeneity at appropriate scales. Such structures probably function to reduce mortality during critical life stages by reducing predation, and providing improved foraging opportunities (Bohnsack et al. 1997). Most studies of artificial reefs to date have focused on highly mobile fauna such as reefassociated or pelagic fishes. Those dealing with benthic resources have addressed fouling organisms (Foster et al. 1994), or epibenthic prey species (Jara & Cespedes 1994) of very low motility. Few have studied the use or impacts of artificial structures on commercially significant decapod crustaceans, which are highly motile within limited ranges. Notable exceptions include studies of Florida spiny lobsters Panulirus argus (Herrnkind & Butler 1986, Butler & Herrnkind 1997, Herrnkind et al. 1997a, Herrnkind et al. 1997b). These researchers have demonstrated that habitat availability limits the abundance of juvenile lobsters, and enhancement with appropriate artificial substrates can greatly increase abundance, whereas artificially increasing the abundance of juveniles by seeding is not effective. Such increases occur primarily through settlement rather than by immigration (Herrnkind et al. 1997a). This project would involve placement of artificial reefs at the appropriate depth for red king crab settlement. Structures that provide a greater variety of interstices in a more compact structure are recommended. Such structures might include crushed rock or gravel, or specifically designed man-made substrata. Objectives: identify appropriate sites for the deployment of red crab substrates; design and construct red crab substrates; deploy substrates. Implementation of this project is relatively simple. A formal project plan, including designs and cost estimates would be developed in consultation with resource agencies. The design of red crab substrates would be guided by evaluating substrates at a reference area located in a similar environmental setting. Implementation would require coordination with the Army Corps of Engineers because it involves placement of fill in navigable waters. Use of the tidelands would require permission from the landowner, for the most of Unalaska Bay this would be either the State of Alaska or the City of Unalaska. Construction of this project would not require any special equipment, skills or expertise that is not locally available. Artificial reef material, including quarry rock, is available locally. Project 11. Small Estuary Enhancement/Captains Bay Goal: increase the functional value of an estuarine intertidal site by enlarging and enhancing it by providing the necessary hydrological control, geometry, bathymetry and substrate for establishment of estuarine conditions, including brackish water habitat and salt marsh vegetation. C-23

13 This project could be done at small estuaries within the Unalaska area where creeks discharge into marine water ands site conditions are suitable. This project would involve placement of artificial reef structures adjacent to existing small estuarine areas of non-anadromous streams to increase retention of tidal water and thereby enhance the estuarine habitat. Objectives: evaluate coastal engineering and hydrology of the site; create an artificial reef/levee to impound water; create a lagoon area for brackish water to accumulate and promote salt marsh type vegetation; stabilize and revegetate disturbed areas; transplant emergent and submerged salt marsh vegetation into lagoon areas; remove trash and debris from area. The design of the sites would be guided by evaluating a reference salt marsh located in a similar environmental setting. Implementation would require coordination with the Army Corps of Engineers because it involves modification of shorelines, dredging and placement of fill in navigable waters. Use of the tidelands would require permission from the landowner, for the most of Unalaska Bay this would be either the State of Alaska or the City of Unalaska. Map 4. Captains Bay Small Estuary Locations C-24

14 Project 12. Artificial Benthic Reefs - Fish Habitat Goal: increase the functional value of marine areas by providing substrate for colonization and cover for fish, eventually resulting in enhanced fish production that could be utilized by recreational, commercial and subsistence fishing interests. Three potential areas for deployment of artificial benthic reefs are Captains Bay, South Channel, and Dutch Harbor. This project would create a new type of habitat where either none or a different type previously existed. Objectives: identify appropriate sites for deployment of artificial reefs; design and construct artificial reefs, deploy reefs at appropriate sites. Implementation of this project is relatively simple. A formal project plan, including designs and cost estimates would be developed in consultation with resource agencies. The design of the artificial reef substrates would be guided by evaluating substrates at a reference area located in a similar environmental setting. Implementation would require coordination with the Army Corps of Engineers because it involves placement of fill in navigable waters. Use of the tidelands would require permission from the landowner, for the most of Unalaska Bay this would be either the State of Alaska or the City of Unalaska. Construction of this project would not require any special equipment, skills or expertise that is not locally available. Artificial reef material, including quarry rock, is available locally. Project 13. Fish Passage Restoration - Morris Cove Goal: restore the functional value of Morris Cove Lake and the small stream that drains it. The functions include access for anadromous fish to spawning and rearing habitat. Full restoration of the site would include rechanneling the stream into the historical streambed. Morris cove is located in the Summer Bay area. The lake and the small stream draining from the lake have historically provided spawning and rearing habitat for pink, coho and sockeye salmon (ADFG ). This project would involve maintenance of fish passage at a small stream that drains Morris Cove Lake. The stream mouth has been cleared several times but it has not lasted. The project would include restoration of the trampled riparian area and removal of debris. An additional, optional component of this project would be to restore and rechannel the stream into its historical streambed, which would create a watercourse of greater length and provide more habitat. Many interviewees favor this option, believing that re-routing might result in a more permanent solution to fish passage. Objectives: maintain access for anadromous fish during periods of migration; avoid unnecessary damage to adjacent meadow and riparian areas; avoid disturbance of archeological sites in area. C-25