Kruzof Island Inventory and Watershed Action Plan

Transcription

1 Kruzof Island Inventory and Watershed Action Plan USDA FOREST SERVICE TONGASS NATIONAL FOREST SITKA RANGER DISTRICT February

2 Overview The Kruzof Island Inventory and Watershed Action Plan (WAP) area (Figure 1)includes six 6 th field hydrologic unit code (HUC) watersheds, one of which (Iris Meadows) is a high priority for protection and restoration on Sitka Ranger District and the Tongass National forest as a whole. A Hydrologic Condition Assessment, incorporating this area was completed as part of the Kruzof Island Landscape Assessment (USDA-FS, 2006). The subwatersheds contained in this report are all contained within the old Kruzof Island 5 th field HUC contained in that report, however, updates to the HUC boundaries at all fields have been made in the intervening years to match national standards. Though some boundaries and acreages have changed slightly, the analysis in that report remains relevant. The Kruzof Island watersheds analysis area, hereafter known solely as the Analysis Area in this document, consists of six 6 th field HUC watersheds, three that flow into saltwater along the eastern shore and three that flow into the western shores of Kruzof Island in Southeast Alaska (Figure 2). Total watershed area within these watersheds is approximately 89,221 acres (135.2 square miles), however all of the watershed boundaries encompass some saltwater areas. For the analysis and summaries in this report, only total land areas will be used. Therefore, the total Analysis Area is approximately 65,844 acres (102.9 square miles). The center of the Analysis Area is located about 15 air miles northwest of the city of Sitka. The Analysis Area is predominantly administered by the Sitka Ranger District of the Tongass National Forest, with a small portion designated as a State Marine Park (1,103 acres; 1.7%), which is administered by the State of Alaska. Historically it was used primarily for subsistence purposes prior to European settlement. Beginning in the late 1950s through the early 1970s, timber production occurred within the Analysis Area under management by the USDA Forest Service, with a total harvest of 6,473 acres. Today, it continues to provide important recreational, subsistence and natural resource opportunities to local residents. Though timber harvest has been curtailed throughout the entire area due to economics and legal factors, current Land Use Designation (LUD) under the 2008 Tongass Land and Resource Management Plan (TLMP) allow for timber management in over half (56%) of the area (Figure 3). The USDA Forest Service has determined that the Analysis Area is vital to the subsistence, recreation, and ecosystem integrity of the area. The Analysis Area and its components have changed significantly since the peak of timber harvest around 1970, and as a result, the USDA Forest Service has identified several predominant issues affecting the current and future landscape and its uses. The issues described in this analysis serve as the basis for recommending actions to rehabilitate many of those ecosystem components in accordance with the Forest Plan. 2

3 Figure 1. Kruzof WAP: Vicinity Map. 3

4 Figure 2. Kruzof WAP: Watersheds. 4

5 Figure 3. Kruzof WAP: Land Use Designations. 5

6 Today, approximately 9.8% percent of the overall Analysis Area and 13.5 percent of the overall riparian old-growth habitat is in a second-growth, even-aged forest structure, which previously served as valuable deer winter habitat. Due to the volcanically formed landscapes over much of the Analysis Area, traditional timber stands only covered slightly over have (52%) of the area (Figure 4). These stands are categorized as consisting of high, medium and low productive old growth (POG), which contains greater than 9000 board feet per acre. The remaining 48% of lands is comprised of muskeg and scrub forest stands. It is recognized that much of the harvested forest stand structure will continue to be even-aged until thinning occurs. Wildlife emphasis thinning treatments to enhance upland deer and bear habitat, as well as Riparian emphasis thinning to enhance tree growth and stream habitats are recommended in this analysis. Approximately 3,400 acres of upland habitat (Figure 7) and 1,460 acres of riparian habitat (Figure 6) are recommended for this type of thinning. Timber production from the Analysis Area has not occurred in the last 40 years, peaking around The Analysis Area is now primarily in the Modified Landscape (ML), Semi-Remote Recreation (SM) and Special Interest Area(SA) Land Use Designations (LUDs), with minor acreage in the Old Growth Habitat (OG)LUD. Only the Special Interest Area and Old-Growth Habitat LUDs do not allow for future commercial timber harvest (Figure 3). Hydrologic connectivity and wetlands are integral parts of watershed function in the Analysis Area. Landslides and soil erosion from timber harvest have been identified as a source of resource damage to downstream ecosystems, and isolated sections of road and stream crossing structures are also contributing sediment. According to the most recent GIS inventory analysis, the Analysis Area contains 222 landslides, which encompass 297 acres. 48 of these landslides, with a contributing area or 73 acres, have reached stream channels and have in some way impacted immediate or downstream habitats. Through field reconnaissance, it has been determined that sufficient regrowth of vegetation has occurred within the vast majority of these landslides and no stabilization efforts are recommended at this point. Furthermore, the majorities of the 72 miles of roads within the area have overgrown with vegetation, are currently in a stable condition or were recently maintained. However, approximately 10 miles of road segments throughout the system are currently contributing, or at-risk of contributing, sedimentation to aquatic habitats (Figure 11). In addition to sedimentation concerns, the road system contains 8 fish stream crossing culverts that do not allow passage. Three of these pipes are Class I and five are Class II pipes. Replacement of all of these 8 nonfunctioning fish stream crossing structures is recommended (Figure 8). Fisheries habitat and aquatic ecosystem function has been impaired along numerous stream reaches due to riparian tree harvest and the conversion from large conifer-dominated riparian areas to red alder or dense, small conifer dominated riparian areas. Approximately 748 acres of riparian management areas (RMAs) that are along Class 1 and 2 streams that are roughly 40 years old are recommended for thinning, along with 712 acres of non-stream RMAs (Figure 6). Additionally, several miles of stream channel were stream cleaned during previous timber harvest activities in the 1960 and 70 s. In-stream rehabilitation of fisheries habitat and other aquatic ecosystem components through the addition of large wood has also been identified on approximately 20 miles of fish bearing stream channels (Figures 9&10). 6

7 Low stream flows along tributary reaches may be an important limiting factor for fisheries of the Analysis Area, especially during below freezing winter periods and extended dry spells in the summertime. Lack of pools due to the absence of large wood is exacerbated by low stream flows, reducing or even eliminating fish rearing habitat by decreasing pool depths and volumes. Extremely low stream flows isolate pools, strand fish, and prevent their access to habitats during critical life stages. Several low gradient valley bottom streams and tributaries within the Analysis Area dry up during dry weather when groundwater is the only source of stream base flows. Past management activities (Tables 1, 2 &3 and Figures 5-11) have had varied levels of influences on hydrologic and aquatic habitat conditions within the Analysis Area. Streamside timber harvest, road construction and stream cleaning undoubtedly had immediate negative impacts to water quality, quantity and health of aquatic species. Though sites have almost entirely reestablished complete vegetative growth, they have not universally stabilized and recovered. Some stream systems have recovered or will recover without assistance, however, many reaches and systems will continue to remain in a declined state, continue to decline further or take many decades to recover without intervention. Current human influences do not appear to be greatly contributing to declining hydrologic condition and aquatic habitat health. Minor and isolated issues of OHV use in unauthorized areas or from irresponsible behavior have occurred, however these impacts are, at least at present, few and far between. Finally, as mentioned previously, the use of the Analysis Area has always been valued by local inhabitants for its important subsistence resources. More recently, recreation, commercial guiding opportunities and sports fishing and hunting uses have joined modern-day subsistence users. Restoration of stream channels and thinning of riparian and uplands stands will almost certainly bring greater recreational, subsistence, and economic importance to the area. Currently, three Forest Service recreational cabin facilities exist within the Analysis Area: the Brent s Beach, North Beach, and Shelikof Beach Cabins (Figure 5). A Forest Service recreational foot trail also connects the Shelikof Beach Cabin and the beach at Port Mary with the road system. Additionally, the Forest Service maintains a three sided survival shelter and mooring buoy at the Mud Bay marine access facility (MAF) on the east side of the island. This MAF provides many locals and guides with off-highway vehicle (OHV) access to the southern and larger road network of the Analysis Area. A second MAF is located several miles to the north of Mud Bay, at the mouth of Eagle Creek. This MAF provides access to the northern portion of the Analysis Area. Projects to both directly enhance or limit recreational or commercial opportunities are not recommended through this analysis, though the resource, habitat restoration and road/trail improvement projects proposed (Figure 11) will indirectly benefit users of the area with greater opportunities for fishing, hunting, wildlife viewing and increased access and safety. 7

8 Figure 4. Kruzof WAP: Vegetation. 8

9 Table 1. Analysis Area Characteristics. Watershed Total Watershed Land Area (acres) Total Forested Area 1 (acres) Harvest (acres) Total RMA (acres) Total RMA Harvested (acres) Fish Stream RMA Harvested (acres) % of Fish Stream RMA Harvested (Class I&II) Total Roads (miles) Open Roads: OHV (miles) Gilmer Bay Iris Meadows Krestof Sound Frontal Shelikof Bay Frontal Sukoi Inlet Frontal - Krestof Sukoi Inlet Frontal - Salisbury Total Source: 2013 Sitka Ranger District GIS Coverage. 1 Includes existing POG (>9mbf/acre) and harvest acres. Table 2. Analysis Area Harvest History Characteristics. Watershed Total Watershed Land Area (acres) Historic POG 2 (acres) 1950s 1960s 1970s Total Harvest % of Watershed in Historic POG % of Historic POG Harvested % of Watershed Land Area Harvested Gilmer Bay Iris Meadows Krestof Sound Frontal Shelikof Bay Frontal Sukoi Inlet Frontal - Krestof Sukoi Inlet Frontal - Salisbury Total Source: 2013 Sitka Ranger District GIS Coverage. 2 Includes existing POG (>9mbf/acres) and harvest stand acreage. 9

10 Table 3. Analysis Area Stream Characteristics Watershed Total Watershed Area 3 (acres) Total Watershed Land Area (Mi2) Total Stream Miles by Class Total Stream Miles within Harvested Stands by Class 4 Fish Pipes Total Total Red Green Gilmer Bay Iris Meadows Krestof Sound Frontal Shelikof Bay Frontal Sukoi Inlet Frontal - Krestof Sukoi Inlet Frontal - Salisbury Total Source: 2013 Sitka Ranger District GIS Coverage. 3 Includes saltwater acreage. 4 Streams that had complete or one side of riparian trees completely harvested without buffers and/or were stream cleaned. 10

11 Figure 5. Kruzof WAP: Island Infrastructure. 11

12 Broad (Landscape) Recommendations Riparian and Upland Thinning Treatment Areas Within the Analysis Area, many of the previously harvested stands associated with riparian areas are approaching or have reached the age and size at which canopy closure has begun. Silviculturists and other resource specialists, including those from fisheries, wildlife, hydrology, and soils, should collectively produce prescriptions for these areas and implement thinning activities within the next ten years. Potential silvicultural treatments should address the desirable species mix, understory biodiversity, and site conditions. General suggestions for implementing riparian regeneration treatments are listed in Appendix G of the Forest Plan. Instream Large Wood Future watershed rehabilitation should include the placement of large wood (LW) into streams currently lacking large wood. Where available, stream survey information should be used to assess the current condition and trends of key stream habitats and to determine the locations at which additional instream LW is needed. Additional stream surveys should be completed in areas impacted by past management activities for which data are lacking. Larger stream channels, such as Shelikof Creek, will involve more intensive surveying and mapping. Road Maintenance and Restoration Roads within the Analysis Area are, for the most part, in decent shape. All of the roads within the Analysis Area have had a complete Road Condition Survey (RCS) completed on them. This data and recent surveys indicate that there are several areas that are in need of restoration and stabilization work. Eleven road segments, totaling 10 miles are experiencing excessive surface erosion from lack of waterbars, crow, sloping or stream capture. Additionally, 8 fish stream culverts are not allowing passage. Restoration work should involve replacing these 8 structures and fixing road segment that are eroding and contributing sediments to stream channels. The public has expressed a desire for more roads and better quality roads to be used for recreation purposes, and as this desire and use (of all kinds) continues to increase, the existing open road systems on the District will become even less adequate and users will likely branch out for new opportunities. Access and Travel Management (ATM) and Off Highway Vehicle (OHV) planning has been completed for the Analysis Area and the entire Sitka Ranger District. This document includes road, foot travel and OHV use. This effort determined what road systems are necessary to meet access objectives and follow with maintenance and rehabilitation plans consistent with protection of soil and water resources. The Forest Service recently announced a rule to require each forest to designate a system of roads, trails and areas slated for motor vehicle use. This designation process is complete and along with the Sitka ATM, OHV use is confined to designated routes and areas, and OHV use off non-designated areas and routes is prohibited. 12

13 Land Use Designations Determine whether LUDs with the Analysis Area meet Forest Plan standards and guidelines. Recommendations Specific for the Analysis Area Develop road rehabilitation plans focused on maintaining natural distribution of surface and groundwater hydrology. Consider second growth management objectives in harvested riparian areas. Primary objective should be recovery of old growth structure and canopy for wildlife and fisheries habitat. Consider second growth management objectives in harvested beach fringe areas. Primary objective should be recovery of old growth structure and canopy to restore/enhance deer winter range habitat. Consider second growth management objectives in harvested upland areas. Primary objective should be recovery of old growth structure and canopy to restore wildlife habitat. Update the existing stream and riparian GIS layers using field verification, digital orthophoto overlays, and aerial photo interpretation. Complete additional stream surveys for representative channel reaches to assess the current condition and trends of key stream habitat within area watersheds. As directed in the 2008 Forest Plan, compare stream survey information (by channel type) to Regional Fish Habitat Variables. Replace or install drivable fords across the existing 8 fish stream crossing structures that currently do not allow fish passage and repair other problem areas identified within the RCS. Add large and key wood to 2.2 miles of the Shelikof Creek main channel to restore fish habitat and stream function. Thin 748 acres in previously harvested fish stream RMAs for Fisheries and Watershed improvements. Thin 712 acres in previously harvested Class III and non-stream RMAs for watershed improvements. Thin 3,406 acres of previously harvested upland areas for wildlife habitat improvements. Add LW structures to the Class I (6.5 miles) and II (11.1 miles) main channel and tributary channels in Analysis Area watersheds to improve channel complexity and fish habitat. Monitor previous instream large wood (LW) and past restoration work within the watersheds. With the help of ADF&G, identify important Brown Bear foraging areas. 13

14 Monitoring and Information Needs A variety of hydrologic information needs are briefly identified here 1. How does seasonal and annual streamflow vary in response to continued climate change? Restore stream gages on the Sitka Ranger District. 2. How do low flows vary during rainless weather in valley bottom and lowland areas? Restore previous/add new district stream gages. 3. How does groundwater influence low flows in watershed with and without management activities? Install monitoring wells on the District. 4. What is the stream temperature regime in these watersheds and their tributaries with respect to state water quality criteria (focus on low flows and harvested reaches)? Install continuous temperature instruments (in conjunction with restored stream gages) and add air temperature recording instruments. 5. What are the long term trends in channel morphology and habitat features along harvested reaches within the Analysis Area? Repeat Tier II surveys and establish monumented Tier III surveys and cross sections. 6. How is LW recruitment in the Analysis Area watersheds affecting LW distribution and function? Tag and monitor key pieces. Restoration Opportunities This section outlines the restoration opportunities designed to meet the objectives for the Analysis Area. The following sections provide detailed project descriptions, objectives, benefits, timelines and estimated project costs. 14

15 Project Descriptions and Implementation Schedule: 1. Kruzof Watershed Group Young Growth Riparian Treatments. Site Type/Description: Current harvested riparian stand compositions consist of dominant Red Alder stands suppressing understory confers as well as densely spaced conifer stands. These stands have little or no understory development. Treatment Objective/Description: Implement thinning strategies that will improve second-growth canopy conditions to improve low flows, riparian wildlife habitat and accelerate dominant conifer tree growth for future sources of instream LW. Objective will involve treatment of 1,460 acres of previously harvested riparian stands to reduce tree density and improve understory development. Thinning treatments should consist of a combination of girdling and thinning alders to release conifers to a minimum 20 foot by 20 foot. Slash treatments such as limbing and bucking should also be implemented to allow wildlife movement, accelerate decomposition and understory development. Slash removal should also be considered. Benefits: Restored stream and non-stream riparian habitat. Increased conifer growth for future sources of LW along 20 miles of Class 1 and 2 fish streams, improved fish rearing habitat to stream channels, improved bank stability and watershed function. Outputs: 1,460 acres of riparian habitat restored Project Phase/FY: Design and Restoration, FY 2014 and beyond Estimated Cost: C I&II RMAs (748 acres): $262,000 (based on $350/acre). 1 CIII/Soils RMAs (712 acres): $250,000 (based on $350/acre) Funding Type(s): NFVW Activity Type: Watershed Stewardship Partnership Contribution: Trout Unlimited, Sitka Conservation Society 1 Priority areas 15

16 Figure 6. Kruzof WAP: Riparian Thinning Treatments 16

17 2. Sitkoh Watershed Group Young Growth Upland Treatments. Site Type/Description : Current harvested stand compositions consist of high density, overstocked conifer stands and Red Alder dominant stands with little understory development. Treatment Objective/Description: Implement thinning strategies that will improve second-growth canopy conditions to improve wildlife habitat. Objectives will involve treatment 1,023 acres of previously harvested upland and beach fringe stands to reduce tree density and improve understory development. Thinning treatments should consist of a combination of girdling, thinning and gap creations to meat wildlife habitat objectives. Slash treatments such as limbing and bucking should also be implemented to allow wildlife movement, accelerate decomposition and understory development. Slash removal should also be considered. Benefits: Restored wildlife habitat and increased understory development to enhance and restore deer winter range habitat and survivability. Outputs: 3406 acres of wildlife habitat restored Project Phase/FY: Design and Restoration, FY 2014 and beyone Estimated Cost: $1,250,000 (based on $350/acre + administration costs) Funding Type(s): NFWF Activity Type: Wildlife Stewardship Partnership Contribution: Mule Deer Foundation, Sitka Conservation Society 17

18 Figure 7. Kruzof WAP: Upland Thinning Treatments 18

19 3. Analysis Area Water Quality, Fish Passage and Habitat Improvements Site Type/Description: 8 culverts within the Analysis currently do not allow fish passage to upstream habitats. Treatment Objective/Description: Remove and replace 8 red fish pipes. Benefits: Restored anadromous and resident fish access, reduced sedimentation and improved watershed function and water quality. Outputs: 8 structures replaced. Project Phase/FY: Design and Restoration FY 2014 and beyond. Estimated Cost: $360,000 (based on $45,000 / structure) Funding Type(s): CMRD, TRTR, NFWF, NFAF Activity Type: Watershed Stewardship Partnership Contribution: Trout Unlimited, Sitka Conservation Society, Grants/Partnerships 19

20 Figure 8. Kruzof WAP: Fish Passage and Habitat Improvements. 20

21 4. Shelikof Creek Stream Channel Restoration Site Type/Description: Due to complete riparian tree harvest associated with past timber harvest, use of the stream channel as a road to remove timber and stream cleaning, a large portion fish habitat within the mainstem Shelikof Creek has significantly degraded. Lack of large and key wood pieces has greatly homogenized instream habitats into large sections of riffles and glides. During low flow periods, lack of deep pool habitat can lead to mortality from freeze out or stranding. During high flow events, the absence of large wood leads to a lack of resting areas as the stream channel turns into a fast water sluice box. Lack of large wood has also lead to instability in stream banks along some reaches, causing bank erosion and sedimentation to aquatic habitats. Treatment Objective/Description: Restoration objectives would be to add large and key wood, in clusters or single pieces throughout the treatment reach to create pool habitat, increase habitat complexity and protect stream banks. Treatments would first include acquisition of (estimate design being completed in FY14) pieces of large wood (18-36 DBH x long). These trees would need to be harvest within the greater project area adjacent to roads capable of use by heavy equipment or imported from an external site. Local wood sourcing would require the majority of the wood to be helicoptered from upland units down to the mainline road for equipment placing or directly to the stream channel. Wood and structure placement on half of the total reach can be completed with heavy equipment, while the remaining portion would necessitate placement with a helicopter due to distance from existing roads and topographical impediments to build temporary roads. Monitoring of the project will include remeasurements of as build monumented cross sections, longitudinal profiles and Tier III habitat surveys. Photo points will also be established. Tongass monitoring protocols will be the guidelines for conducting monitoring and schedule will include yearly monitoring for the first 3 years post completion, followed by 3-5 increments after that. Benefits: Enhance anadromous fish habitat, reduced sedimentation and improved watershed function and water quality. Outputs: 2.2 miles of stream channel enhancement. Project Phase/FY: Survey/Design - FY13 (funded), NEPA FY14. Estimated Implementation Cost: $550,000 (estimate) Funding Type(s): NFVW, NFWF, NFAF Activity Type: Watershed Stewardship Partnership Contribution: Trout Unlimited, Sitka Conservation Society, ADF&G, NOAA, other Grants/Partnerships 21

22 Figure 9. Kruzof WAP: Shelikof Creek Stream Channel Restoration. 22

23 5. Kruzof Watersheds Stream Channel Restoration Site Type/Description: Due to complete riparian tree harvest associated with past timber harvest, use of some stream channels as roads to remove timber and stream cleaning, numerous portions of mainstem and tributary channel fish habitats within the Analysis Area have been significantly degraded. Lack of large and key wood pieces has greatly homogenized instream habitats into large sections of riffles and glides. During low flow periods, lack of deep pool habitat can lead to mortality from freeze out or stranding. During high flow events, the absence of large wood leads to a lack of resting areas as the stream channel turns into a fast water sluice box. Lack of large wood has also lead to instability in stream banks along some reaches, causing bank erosion, channel widening and sedimentation to aquatic habitats. Treatment Objective/Description: Treatments would consist of using USFS personnel and possible volunteers to hand place pieces of large wood into stream channels to improve fish habitat and stabilize streams. Pieces of large wood will be recruited from existing riparian stands or from downed wood adjacent to stream channels. Placement will be in cluster jams, designed structures, single random pieces and cover structures. Monitoring of the project will include completing pre and post photo points, as well as possible establishing permanent cross sections, longitudinal profiles and Tier II/III habitat surveys in certain critical reaches. Tongass monitoring protocols will be the guidelines for conducting monitoring and schedule will include yearly monitoring for the first 3 years post completion, followed by 3-5 increments after that. Benefits: Restored anadromous fish habitat, reduced sedimentation and improved watershed function and water quality. Outputs: 17.8 miles of stream enhancement (Class I: 6.5 miles; Class II: 11.1 miles). Project Phase/FY: Surveys FY12 (completed); NEPA FY13 (funded), Implementation FY14 and beyond. Estimated Implementation Cost: $445,000 (based on $25,000/mile) Funding Type(s): NFVW, NFWF, NFAF Activity Type: Watershed Stewardship Partnership Contribution: Trout Unlimited, Sitka Conservation Society, ADF&G, NOAA, other Grants/Partnerships 23

24 Figure 10. Kruzof WAP: Kruzof Island Force Account Instream Restoration. 24

25 6. Kruzof Island Road and OHV Trail Improvements Site Type/Description: 10 miles of OHV trail are experiencing failures and/or creating resource damage (erosion, stream capture or cut bank/fill slope failure) Safety concerns are also associated with many of these sites. Treatment Objective/Description: Restore trail surfaces to correct failures. Treatments include, resurfacing, rebuilding and/or reshaping road surfaces, road prisms, and stream crossing fords, as well as the installation of water bars. Benefits: Decrease sedimentation to aquatic habitats and improve user safety. Outputs: 10 miles of trail restored. Project Phase/FY: Design and Restoration FY14 and beyond. Estimated Cost: $?????? Funding Type(s): CMRD, TRTR, NFWF, NFAF, Recreation Activity Type: Watershed Stewardship Partnership Contribution: OHV User Groups, Grants/Partnerships 25

26 Figure 11. Kruzof WAP: Road and OHV Trail Improvements. 26