Streamlined Consultation Guidance for Restoration/Recovery Projects (RRP): Format for the Biological Evaluation/Assessment

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The attached biological evaluation/assessment (BE/BA) was developed pursuant to the Fish and Wildlife Service’s Streamlined Consultation Guidance for Restoration/Recovery Projects. The BE/BA meets all of the criteria for an expedited consultation process set forth in that policy document.

Unique Places hereby requests expedited formal consultation for the Hoosier Dam Removal Project.

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Signature of Requesting Action Agency Official Date

Biological Evaluation/ Hoosier Dam Removal Project Chatham County, NC Assessment Cape Fear River Basin June 2017 HUC 03030003

Prepared By: Unique Places, LLC PO Box 52357 Prepared For: Durham, NC 27717 US Fish and Wildlife Service Phone: 919‐724‐0676 551 Pylon Drive Raleigh, NC 27606 Wildlands Engineering, Inc Phone: 919‐856‐4520 312 W. Millbrook Rd., Suite 225 Raleigh, NC 27609 Phone: 919‐851‐9986 I. Description of the Proposed Restoration/Recovery Action [include maps, photographs, diagrams, etc. as appropriate] A. Description of the Restoration/Recovery Objective(s) 1. Briefly describe the restoration and specific recovery action (citing source document when applicable) and its intended beneficial impact to the species. The Hoosier Dam is a 94‐year‐old hydroelectric dam located on the Rocky River 5 ½ miles upstream of its confluence with the Deep River in Chatham County, North Carolina (Figure 1). The dam is being proposed for removal as part of a National Fish and Wildlife Foundation (NFWF) grant to restore the Rocky River from its currently impounded state back to a free‐flowing state. Hoosier Dam and its impoundment, Reeves Lake (Figure 2), are responsible for the loss of natural flow regime, sediment regime, and shallow water habitat to approximately 18,138 linear feet of stream ecosystem (16,060 linear feet within the Rocky River and 2,078 linear feet of perennial tributaries). The U.S. Fish & Wildlife Service (USFWS) has designated sections of the Rocky River upstream of the impoundment and downstream from Hoosier Dam, as well as a section of Bear Creek just below the dam, as Critical Habitat for the Cape Fear shiner, a federally listed endangered species (USFWS, 1988) (Figure 3). The non‐impounded sections of the Rocky River and Bear Creek exhibit very high quality riverine habitat that supports a diverse collection of aquatic species including the Cape Fear shiner and other species of concern, such as the eastern creekshell (Villosa delumbis), the Carolina creekshell (Villosa vaughaniana), the Savannah Lilliput (Toxolasma pullus), and an undescribed Lampsilis sp.. (photographs in Appendix A). The dam represents a significant blockage to aquatic species ability to disperse freely and exchange genetic material with neighboring populations and as a result, USFWS has documented declines in the disconnected Cape Fear shiner population upstream of the dam (USFWS, 1988). Removal of the blockage created by the dam to provide access to these high‐quality reaches would be of substantial long‐term benefit to aquatic communities including the Cape Fear shiner. The recovery goals for the Cape Fear shiner, as listed in the 1988 USFWS report are: 1. Protection of existing populations and successful establishment of reintroduced populations and current habitat; 2. Evaluating feasibility of introducing species into historic habitat; 3. Searching for additional suitable habitat for re‐introduction; 4. Monitoring existing populations biannually; and 5. Evaluating the recovery program on an annual basis. The removal of the Hoosier Dam, and restoration of the Rocky River in the vicinity of the dam will address the habitat recovery goals of the Cape Fear shiner listed above. Post‐dam removal, the previously impounded stretch of the Rocky River will return to its historic wide, shallow, and rocky state. This will immediately provide 3.4 additional miles of historic habitat for the Cape Fear shiner that is directly connected to existing habitat and known populations of the species. This expansion of available habitat is expected to be naturally repopulated as shiners move into the area. Impoundments and siltation from impoundments is listed as one of the key elements in the decline of the Cape Fear shiner population (USFWS 1988.) This project will directly address such an impact. Removing the dam will prevent further siltation of habitat within the currently impounded reach of the Rocky River. The construction plan itself will address the existing sediment wedge behind the dam. The wedge will be removed prior to construction if testing of the wedge after dewatering confirms a dominant fine silt/clay/sand texture. Sediment in the wedge will be pulsed through the system during construction if testing confirms the wedge to be a medium gravel to cobble texture (refer to Sediment

Management Plan in Appendix C for full description). Removal of the dam will restore a natural sediment regime to the Rocky River. The current impoundment not only traps fine sediment, but also the gravels and cobbles that comprise the preferred Cape Fear shiner habitat. Currently, if gravel and cobbles are washed downstream in the habitat below the dam, they are not being replaced by new material entering the system, damaging existing habitat. 2. Include a description of anticipated habitat improvements, and/or expected increases in species fitness, survivorship, etc. that are consistent with the recovery needs of the species. The impounded portion of the Rocky River, shown in the photo to the left, is an open, freshwater, lentic habitat. Water depth is approximately 25 feet at the upstream face of the dam and gradually decreases in the upstream direction. The impoundment is narrow through the majority of the river length and widens for the last 1,000 feet before the dam. Habitat is suitable for lentic species of fish, macroinvertibrates, vegetation, and waterfowl. Draining the impoundment and removing the Existing Impoundment (Reeves Lake) dam is expected to return the Rocky River to its historic bed conditions. These conditions are likely to mimic those upstream of the impoundment and downstream of Hoosier dam (pictured right). The river will have wide, shallow waters interspersed with bedrock outcrops, pools, natural riffle features, and deposits of large woody debris. This is consistent with the habitat needs of the Cape Fear shiner. In addition to geomorphic habitat restoration, the removal of Hoosier Dam will restore many natural processes that will benefit the Cape Fear shiner and other sensitive aquatic species. Water temperature and oxygen levels will change in the Rocky River’s impounded reach once the dam is removed. Previous temperature and dissolved oxygen stratification testing done by Wildlands Engineering (Wildlands) in 2013 within the impoundment showed stratification of temperatures ranging from 26.8 C at the surface to 22.2 C at a depth of 19 ft. In a study of the Cape Fear shiner by Hewitt et al. (2006), Downstream of Hoosier Dam the habitats with the best survivability and growth rate had temperatures ranging from 26.4C to 28.1C. This range was only achieved on three sampling dates and only within the top four feet of lake depth. Since the river will be restored to a shallow water condition, it is more likely to maintain these temperature ranges preferred by the shiner and provide suitable habitat for species re‐ establishment. Wildlands 2013 dissolved oxygen (DO) samples showed a dramatic decrease in DO concentrations in the first six feet of depth, typically dropping from 8 mg/L to 5 mg/L within the first four feet of depth. The aforementioned study by Hewitt et al. (2006) indicated the best habitat for Cape

Fear shiner has a DO range of 5.8 – 12.5 mg/L. Restoration of a shallow free‐flowing river will improve habitat conditions within the vicinity of the impounded reach by increasing DO levels and eliminating the drastic stratification existing in the impoundment. Natural sediment transport processes will be restored through removal of the Hoosier Dam. As discussed in the section above, reintroduction of a natural sediment regime will enhance habitat located in the impoundment by flushing fines and removing the sediment wedge, but it will also allow gravels and cobbles that have been trapped behind the dam to coarsen downstream riffles located in the Critical Habitat Area that have been previously starved of sediment. Pebble Counts conducted above and below the impoundment show that riffles below the dam have smaller amounts of coarse gravel and small cobbles, confirming the effect of an interrupted sediment regime. Additional details on sediment composition can be found in the Sediment Management Plan in Appendix C. 3. Explain why there is a high certainty that implementation of the proposed action is likely to achieve its intended restoration/recovery objective under the second Criterion for Inclusion. This explanation should rely on either a proven track record or a high level of certainty that the habitat improvements are likely to cause the desired species response. Dam removals have been performed extensively throughout the United States to remove barriers to aquatic organism passage and return impounded waters to historic lotic conditions. In North Carolina, the Carbonton Dam was removed under similar conditions and project goals to this project including benefits to Cape Fear shiner habitat. The Carbonton Dam was a run of the river hydroelectric dam facility located on the Deep River approximately nine miles west of Sanford North Carolina. The concrete buttress dam was built in 1921, averaged 27 feet in height, and had a crest of 260 feet (Restoration Systems, 2005). Similarly, the Hoosier Dam is a run of the river hydroelectric dam facility with a concrete buttress structure. Hoosier Dam was built in 1922, averages 25 feet in height, and has a crest of 235 feet. The Carbonton Dam removal was part of a NCDEQ‐Division of Mitigation Services full delivery project created to deliver mitigation credits for impacts to waters of the United States. Project goals for the Carbonton Dam removal were similar to this project and included restoration of a lotic ecosystem and provision of habitat for the endangered Cape Fear shiner. The project was monitored for five years post‐ dam removal. After two years, the Cape Fear shiner presence was recorded at eight of their 14 monitoring stations, with available habitat increasing each monitoring year (Restoration Systems, 2010). The project can be considered a success for the restoration of Cape Fear shiner habitat. The Hoosier Dam removal will occur under similar conditions. It is in the same geographic and geologic region, with similar potential for restoration of shallow, wide, rocky habitat for the Cape Fear shiner. Potential risk factors for the project, such as temporary sedimentation, are accounted for in conservation management measures discussed in Section 1D, below. No risk factors are evident that would inhibit the development of a lotic ecosystem with a variety of habitat niches for aquatic species. The presence of Cape Fear shiner in the previously impounded section of the Deep River within two years of dam removal indicates that the species will enter adjacent newly available habitat. 4. Describe over what time frame the conservation benefits of the proposed action are expected to accrue. The Rocky River will experience immediate alteration upon removal of the Hoosier dam and the small remnant dam upstream. The geomorphology, flow regime, and sediment regime will adjust back towards conditions present in the river prior to the construction of Hoosier Dam. It is anticipated that within the first six months, half of the sediment affected by the dam removal will be pulsed through the system as a result from the change in geomorphology (an increase in channel slope from the removal of

3 the impoundment). Then over time the remaining sediment may flush through the system on an episodic basis corresponding to large storm events (Collins et al., 2017; Pearson et al., 2011.). This process is expected to return the Rocky River to a shallow water system with a gravel substrate suitable for the colonization of the Cape Fear Shiner. The Cape Fear shiner can migrate into the previously impounded section of the Rocky River from existing populations located upstream of the impoundment and downstream of the dam (Figure 3). This may take place over a number of years, eventually fully connecting the Upper Rocky River Aquatic Habitat to the Lower Rocky River/Lower Deep River Aquatic Habitat and the Bear Creek Aquatic Habitat, greatly expanding the available habitat and spawning areas for the Cape Fear shiner. The timeframe it may take to reestablish the shiner population throughout the former impoundment is unknown, however, there are no projected impacts to the river that would prevent this progress. B. Define the Action Area Construction activities will be isolated to the lower section of the impoundment and the area immediately surrounding Hoosier Dam (approximately 1,000LF) to perform the dam removal, potential removal of the sediment wedge, streambank stabilization, bed stabilization, habitat structure construction, and re‐vegetation (Figure 4). Revegetation may also take place upstream in areas affected by the drawdown of the impoundment. The entirety of the impoundment (with an upstream boundary just below Pittsboro Goldston Road and a downstream boundary just below Hoosier Dam) will be directly and indirectly affected by the removal of the Hoosier Dam. The entire impounded area, including tributaries shown in Figure 4, will by hydrologically affected by the removal of the dam. A lotic flow regime will be reestablished and the channel cross‐sections will alter to adjust to the new hydrology. Shallow, rocky sections of river may be exposed and the habitat niches will transition from lentic to lotic. Short term impacts may occur directly downstream of the dam as the Rocky River adjusts to the geomorphic change in the river following removal of the dam. The following is the proposed project timeline:  Dewatering of the impoundment: June 2017‐July 2017 o Actions concurrent with dewatering: . Relocation of mussel species affected by dewatering; . Seeding and stabilizing exposed streambanks; . Evaluation of sediment wedge upstream of dam; and . Continual monitoring of turbidity.  Collection of sensitive mussel species below the dam for relocation: Prior to dam removal, July/August 2017.  Removal of Hoosier Dam and Powerhouse Structure: August/September 2017 o Actions concurrent with dam removal: . Removal of sediment wedge (if wedge is fine sediment), pulsing of sediment (if wedge is course sediment); . Removal of the remnant rock dam located approximately 4,800 feet upstream of Hoosier Dam (incorporate these boulders into habitat enhancement structures on Rocky River) . Stabilization of streambanks post‐dam removal; . Stabilization of stream bed using grade control structures; . Implementation of habitat structures within stream bed/banks; and . Re‐establishment of a riparian buffer with planting of native woody species along streambanks.

C. Project Implementation The following federal agencies are involved in permitting and approving the Hoosier Dam Removal Project. Communication and correspondence with all agencies discussed below, in Table 1, is ongoing. Pre‐application meetings with agencies have been held and dates are included in the Table.

Table 1: Federal Agencies involved in Hoosier Dam Removal ‐ Hoosier Dam Removal Project Associated Permits/ Federal Agency Required Action Status submittals Nationwide 53 (dam removal), Nationwide 27 Coordination and receipt Pre‐application meeting US Army Corps of (stream restoration of appropriate permits with USACE held March Engineers activities) and/or prior to dam removal and 15, 2017. Permits to be Nationwide 13 (Bank restoration activities applied for June 2017. Stabilization) Biological Assessment for the Cape Fear shiner, Submittal of Biological US Fish and Wildlife consultation on Assessment so USFWS can BA submitted to USFWS Service dewatering plan and submit Biological Opinion May 30, 2017 sediment management to USACE for permitting plan Submittal of Drawdown Request prior to Drawdown request Federal Energy Drawdown Request, drawdown of submitted June 12, 2017. Regulatory Surrender of FERC impoundment, and FERC variance approved Commission Exemption submittal of FERC June 15, 2017. Exemption variance prior to dam removal Submittal of no‐rise Coordinated with local technical memo prior to Federal Emergency Floodplain Administrator. Dam removal is exempt restoration activities and Management Agency Submitting No‐Rise May CLOMR post restoration 30, 2017. activities

The removal of the Hoosier Dam will follow the procedure and timeline outlined in Section 1.B, above. Table 2, below, lists the activities associated with the project that are likely to have a temporary or long term beneficial or adverse impact to the Cape fear shiner.

Table 2: Project Activities and Their Potential Impact ‐ Hoosier Dam Removal Project Potential Description of Potential Impact to Effect on Project Activity Activity Description Description of Potential Impact to Species Habitat Cape Fear shiner During dewatering, turbidity and effluent flowrate will be monitored to keep at levels set by USFWS (< 50 NTUs, and approximately 50 cfs above baseflow, respectively) in order May Affect Dewatering of to reduce potential impact to aquatic life. Drawdown Dewatering of but not Impoundment. Please should maintain a rate of approximately one foot per day. Reeves Lake likely to refer to Dewatering High turbidity levels (>50 NTU) and changes to flow regime (impoundment) Adversely Plan in Appendix B. due to dewatering could force species to move Affect downstream from immediate vicinity of Dam. An adaptive management plan will be in place to respond to any rises in Potential increase in turbidity may turbidity during dewatering. have an effect of temporarily silting in Cape Fear shiner habitat. In addition to installing and maintaining erosion and However, any siltation would likely sediment control devices during construction, turbidity be flushed out during the next storm Installing erosion and within the river will be monitored directly downstream of event. May Affect sediment control the dam removal. Construction protocol will follow the Erosion and but not devices prior to start of same protocol set forth in the dewatering plan, where if the Sediment likely to construction activities turbidity increases above 50 NTUs construction will cease Control/Site setup Adversely and maintaining them and any sediment input will be addressed (if caused by Affect during construction construction and not natural hydrologic events). It is likely that turbidity will increase during construction even with the presence of erosion and sediment control devices.

Removal of the dam will benefit stream temperatures, Dam will be removed dissolved oxygen levels, hydrologic regime, and sediment Dam removal will open up 3.4 miles Removal of from the Rocky River regime within previously impounded reach and of potential habitat for the Cape May Affect Hoosier Dam according to Final downstream reach of Rocky River. The initial act of removal Fear shiner. Construction Plans could have a temporary impact or take of the species due to construction activities.

Potential Description of Potential Impact to Effect on Project Activity Activity Description Description of Potential Impact to Species Habitat Cape Fear shiner Removal of the hydroelectric powerhouse will allow for the Deconstruction and Rocky River to have a more stable planform with less Removal of the powerhouse allows Removal of removal of the potential for bank erosion and downstream sedimentation for complete removal of the May Affect Powerhouse hydroelectric post‐dam removal. The initial act of removal could have a structure and opens up further powerhouse temporary impact or take of the species due to habitat for the shiner. construction activities If sediment wedge behind dam is found to Sediment will not be pulsed be coarse, sediment If sediment behind the dam is found to be coarse in nature, downstream if it has a high potential May Affect Potential pulsing of may be pulsed there is less danger of it affecting the Cape Fear shiner of silting in shiner habitat. There but not sediment downstream during population. However, there could be a temporary impact as may be temporary deposition of likely to downstream deconstruction. Refer sediment pulses through the system within the first few sediment within the system, but it Adversely to Sediment months after removal. would be flushed out with the next Affect Management Plan in storm event. Appendix C. This change in bed formation will benefit the Cape Fear After removal of the shiner as it will greatly increase the amount of riffle habitat Reformation of dam, the riverbed will within the newly drained impoundment. Channel bed Reformation of the channel will not channel banks and be stabilized with rock material will coarsen over time within the previously impact any existing shiner habitat, bed (with structures if needed. If impounded section of Rocky River and the baseflow level May Benefit but will create potential shiner hydrologic regime bedrock is exposed, it will decrease in depth similar to upstream and downstream habitat. change) will remain in place as conditions. Available habitat will also increase for the a natural grade control American Water Willow (Justicia Americana), a native plant species present in the Cape Fear shiner habitat. Stabilization of Re‐vegetating stream banks will limit potential for erosion Bank stabilization and re‐vegetation exposed banks through and sedimentation in the Rocky River. This will help will not negatively impact any Bank Stabilization revegetation and maintain a coarse bed material texture. Re‐vegetating will existing shiner habitat, but may May Benefit and re‐vegetation potential grading. Re‐ also provide areas of refuge along the streambanks for improve quality in potential shiner vegetation of newly aquatic species including the Cape Fear shiner. habitat. exposed floodplains

Potential Description of Potential Impact to Effect on Project Activity Activity Description Description of Potential Impact to Species Habitat Cape Fear shiner Installation of instream or streambank Implementation of habitat Habitat structures including rocky riffle and lunker logs Habitat Structure structures for the structures will not negatively impact provide instream and near streambank habitat for aquatic May Benefit implementation purpose of providing any existing shiner habitat but may species including the Cape Fear shiner habitat niches within create potential shiner habitat. the Rocky River

D. Conservation Measures Specific management practices will be put in place for the demolition of Hoosier Dam and restoration of Rocky River to avoid and minimize adverse impacts to the Cape Fear shiner and its habitat. These are discussed below. Management of Dewatering Dewatering the impoundment is the first phase of the project. The timing of dewatering is critical to minimizing impact on Cape Fear shiner populations downstream of the impoundment. Summer was chosen for drawdown based on consultation with the USFWS for the following reasons:  Baseflow in the channel is at its lowest between June and September. This allows for better control over dewatering and limits the likelihood of the impoundment levels rising and falling, potentially harming aquatic species with the water level fluctuations. Low baseflow conditions also allow for better access to exposed sediments behind the dam, aiding in mechanical removal if deemed necessary.  The summer timeframe is after the window of spring reproductive activity when sensitive life stages associated with spawning and larval development of rare mussels and Cape Fear shiner occur.  Aquatic species surveys are easier in the summer months. Water temperatures allow for human access for species surveys and relocations. The rate of dewatering was developed after consultation with USFWS to limit impact on aquatic species. The drawdown rate will be kept at a maximum of one vertical foot per day. This will allow for stabilization of streambanks with grasses and the collection of any stranded mussels along the impoundment. Turbidity monitoring will be conducted daily during the drawdown period and will commence two weeks before drawdown and extend two weeks following completion of the dewatering. The turbidity will be sampled approximately 100 feet downstream of the power facility. An additional turbidity measurement will be taken weekly within the impoundment that will be sampled from the catwalk attached to the powerhouse. Based on feeback from NC Wildlife Resource Commission (NCWRC) and USFWS a maximum threshold of 50 NTUs will be adhered to during the dewatering process. It is understood that mussels can tolerate short term spikes in turbidity and that it may not be advisable in a high turbidity event to maintain open flow conditions (i.e. not mechanically reduce or stop flow). If turbidity approaches the 50 NTU threshold, Unique Places (UP) staff will immediately contact the NCWRC and USFWS staff to discuss the situation. An action plan will be developed and formalized based on current river conditions, expected rain falls, gauge station data, etc. The prescribed actions to adjust flow (if any) will be implemented immediately by UP staff. Additional information on dewatering is discussed in detail in the dewatering plan in Appendix B. Management of Construction Removal of the Hoosier Dam and the restoration of the Rocky River will adhere to a permitted erosion and sediment control plan through the NCDEQ Division of Energy, Mineral, and Land Resources. Dam removal will be completed to limit impact and contact of equipment, sediment, and materials with the river bed and water column. During dam removal, streamflow will be routed through the existing powerhouse. This will leave dry access to the dam itself. The dam will be removed from the top of the dam down, in small vertical sections. Once material is removed it will be placed in the river within the

9 footprint of the dam itself, to allow construction equipment to walk across the streambed on a concrete pad. Once the dam is fully deconstructed, the pad will be removed. Water will then be turned into the center of the channel, and the powerhouse will be removed. The ability to continue a natural flow regime during dam removal will reduce potential impact on downstream aquatic species. Not having to utilize pumps protects aquatic species from being inadvertently pumped through the system. Additional erosion control features will include silt fence along any staging and stockpile areas and stabilizing exposed banks with erosion control matting and temporary and permanent seed. All erosion control features will be monitored regularly as well as turbidity downstream of the construction site for the purpose of preventing sedimentation of downstream aquatic habitat. Turbidity protocol and management will follow that outlined in the dewatering plan. E. Monitoring and Reporting Plan Monitoring of the Cape Fear Shiner will take place for three years following removal of the dam to document project success. Three locations have been chosen because they have existing survey data on the Cape Fear shiner that can be used for comparison. The fourth will be within the previously impounded reach. Sampling locations are: 1. Upstream of the bridge crossing at Pittsboro‐Goldston Road (Upsteam of impoundment) 2. The previously impounded reach 3. In the trailrace of the dam 4. At Chatham Church Road Monitoring will be conducted via seining suitable habitats for a standard time duration and number of seining efforts (to be determined). All monitoring will be performed by a qualified and permitted crew once a year for up to three years. If Cape Fear shiner are detected at Pittsboro‐Goldston Road, the trailrace of the dam, and Chatham Church Road during the first or second year of monitoring, then sampling in these areas may be discontinued early. Sampling in the impounded reach should continue for the full three years.

II. Status of the Species and Critical Habitat in the Action Area‐ Environmental Baseline

Table 3: Federally Listed Species Status ‐ Hoosier Dam Removal Project Suitable Habitat Species Habitat Association Federal Status in Action Area Gravel, cobble, and boulder substrate Cape Fear shiner (Notropis around aquatic vegetation found in slow Endangered Yes mekistocholas) moving pools, riffles, and slow runs.

Suitable habitat for the Cape Fear shiner is located within the Action area for this project. The suitable habitat area is located at the base of the dam and continues downstream of the project. The Cape Fear shiner habitat upstream of the impoundment will not be impacted by the activities associated with this project. A. Notropis mekistocholas (Cape Fear shiner) The Notropis mekistocholas, endemic to the Cape Fear River basin, has sustained segmented populations for several decades; however, environmental stressors are still contributing to the species decline. Dams and impoundments that create habitat fragmentation and degradation are the primary culprit for these restricted populations. Currently, the Hoosier Dam and its impoundment is hindering potential connectivity for the Cape Fear shiner. Limited genetic variation can be detrimental to the survivability of a population. Considering the life span of the Cape Fear shiner is approximately 2‐3 years, both existing and developing stressors prevent research and

10 monitoring opportunities to learn more about their behavior, biology and ecology. The Cape Fear shiner has not been found in the impoundment; however, populations have been confirmed upstream and downstream. Currently, the Hoosier Dam has altered the riverine habitat resulting in demographic consequences for the aquatic species, especially the Cape Fear shiner. Within confirmed locations, the Cape Fear shiner has been seined in shallow waters around American water‐willow (Justicia Americana). Emergent vegetation provides mesohabitats serving as refuge, possible food source and locations for depositing and attaching eggs to the substrate associated around willow beds and other riparian vegetation. The existing lentic ecosystem of Reeves Lake has engulfed all microhabitats which are necessary for distribution and reproduction of the Cape Fear shiner and similar species. Furthermore, impoundments act as a reservoir for predators such as the Roanoke bass (Ambloplites cavifrons), crappie (Pomoxis sp.) and the flathead catfish (Pylodictis olivaris), which is an introduced obligate carnivorous species (Hewitt et al., 2009 and USFWS, 1988). While the adult catfish do not occupy the same habitat as the Cape Fear shiner, the juvenile catfish do share habitat and could pose as potential threat. Dams also act as a holding tank for contaminants which ultimately affect water quality. Suitable habitats required for early development may be essential for this species’ success. The Cape Fear shiner has been found in slow pools, shallow side waters and run/riffle complexes throughout their range indicating velocity breaks with healthier water quality and various depths with mixed substrates are indicative of suitable habitat for the life stages of this species (USFWS, 1988). Removal of the Hoosier Dam and restoring riverine habitat within a lotic ecosystem will allow natural features that establish vegetation growth, provide proper spawning grounds, and decrease predation risks. The project would contribute to long‐term conservation efforts of the Cape Fear shiner and provide the historical habitat that is necessary to support their population recovery. B. Cape Fear Shiner Critical Habitat As defined in the Cape Fear Shiner Recovery Plan, USFWS designated sections of the Rocky River upstream of Reeves Lake and downstream of the Hoosier Dam, along with a section of Bear Creek just below the dam, as Critical Habitat for the Cape Fear shiner (USFWS, 1988) (Figure 3). According to USFWS, “the constituent elements for the Cape Fear shiner include clean streams with gravel, cobble and boulder substrates with pools, riffles, shallow runs and slow water areas with large rock outcrops, side channels and pools with good water quality and relatively low silt loads.” Due to the Hoosier Dam, this particular section of the Rocky River does not contain any of the constituent elements but instead the impoundment has inundated the natural features and accumulated a sediment load behind the dam. III. Effects of the Action and Cumulative Effects A. Notropis mekistocholas (Cape Fear Shiner) Any potential adverse impacts are believed to be temporary. During the dewatering process, the drawdown of approximately one foot per day will expose streambanks, some turbidity will occur and the potential effluent flowrates could push the species downstream. The main area of concern will be immediately downstream of the dam removal where fine sediment could be displaced. Measures will be set forth to control and prevent mass erosion or excessive turbidity. For example, seeding will be placed along streambanks to provide streambank stability and decrease siltation. There should be very limited take, if any, upstream of the Hoosier Dam removal. The controlled lowering of the impoundment would provide opportunity for the Cape Fear shiner to reach maximum dispersal distances over time having a positive impact on population levels. The sediment management

11 plan and the scheduling of the project will prevent adverse impacts to the population downstream and would be minimal, if any take does occur. The alteration from a lentic ecosystem to a lotic ecosystem will manipulate the existing habitat and its function. However, the lotic ecosystem will develop and enhance habitat and the habitat function for both aquatic and terrestrial species, serving as a wildlife corridor upstream, downstream and across, whereas the impoundment and Reeves Lake is currently an obstacle for wildlife species. The action will create a permanent gain of habitat and habitat function. The project will develop long‐term beneficial impacts by connecting approximately three miles of improved riverine habitat which will allow for demographic dispersal, genetic diversity and species richness. Specifically, characteristics such as higher dissolved oxygen levels, stable water temperatures, consistent hydrologic and sediment regime will establish microhabitats within and around run/riffles complexes, shallow pools and woody debris throughout the reach. The establishment of new vegetation along streambanks, on bars and islands of rock outcrops will provide refuge from predation for aquatic species, including the Cape Fear shiner, which is crucial for larval and young to reach their first year of reproductive maturity. The beneficial cumulative effects such as reducing predation, healthier water qualities, and extending the upstream riverine habitat downstream to the confluence of the Deep River and Rocky River would enhance the Cape Fear critical habitat through the Action Area and provide grounds for further research and monitoring of Cape Fear shiner populations. The long‐term benefits are expected to outweigh the short‐term impacts to the species. B. Cape Fear Shiner Critical Habitat If any adverse impacts should occur within the critical habitat, they should be short‐term and small in magnitude since controlled measures will be implemented to alleviate any severe or long‐term impacts; therefore, this project and its temporary in‐water work actions should not result in Adverse Modification to designated Cape Fear shiner Critical Habitat. As mentioned earlier, erosion and sediment control devices will be utilized and monitoring turbidity levels will be on‐going throughout the process to reduce potential impact to the aquatic species, along with seed application to streambanks to provide bank stabilization. Restoring the essential habitat features, primary constituent elements (PCEs) and/or physical or biological features (PBFs) is the goal of this project. This project should allow enhancement of the conservation support function by establishing connectivity between the upstream and downstream critical habitat. Returning the river to its historical habitat, within the Action Area, will provide another migration site for the Cape Fear shiner or facilitate the augmentation of reintroduced populations. There will be a gain of critical habitat and functional value of critical habitat over time. These beneficial effects to the species will be long‐lasting. The negative effects associated with the dam and its impoundment will be removed with the demolition of the dam. Construction itself, and potential associated sediment loads, may cause temporary stress to any Cape Fear shiner in the immediate vicinity of the dam. However, stress should be temporary in duration. The outcome of this project will re‐establish the primary constituent elements of the designated critical habitat essential to the conservation of the Cape Fear shiner.

IV. Conclusion‐Determination of Effect The removal of the Hoosier Dam and restoration of the Rocky River is likely to have an overall, long term, beneficial effect on the Cape Fear shiner population and available habitat. Demolition and construction activities discussed herein May Affect and are Likely to Adversely Affect the Cape Fear

12 shiner. Incidental take is possible in the form of harassment due to machinery and noise in the immediate area, and potential harm/death during the dewatering and demolition/construction stages of the project, but the take will not rise to the level of jeopardy of the Cape Fear shiner, nor will it adversely modify or destroy the designated critical habitat upstream and downstream of the project areas Management practices will be used to prevent incidental take as much as possible.

V. List of References and Personal Communications Collins, M.J., Snyder, N.P., Boardman, G., Banks, W.S.L., Andrews, M., Baker, M.E., Conlon, M., Gellis, A, McClain, S., Miller, A., and Wilcock, P., 2017. Channel response to sediment release: insights from a paired analysis of dam removal. Earth Surface Processes and Landforms, doi: 10.1002/esp.4108 Hewitt, Amanda H. et al. 2006. Influence of Water Quality and Associated Contaminants on Survival and Growth of the Endangered Cape Fear shiner (Notropis Mekistochoias). Environmental Toxicology and Chemistry. 25:9. Pp. 2288‐2298. Hewitt, Amanda H., Kwak, Thomas J., Cope, W. Gregory, and Pollock, Kenneth H. 2009. Population Density and Instream Habitat Suitability of the Endangered Cape Fear Shiner. Transactions of the American Fisheries Society. 136:6. Pp 1439‐1457. Pearson, A.J., Snyder, N.P., and Collins, M.J., 2011. Rates and processes of channel response to dam removal with a sand‐filled impoundment. Water Resources Research 47:W08504, doi: 10.1029/2010WR009733 Restoration Systems, LLC and Ecoscience Corporation. 2005. Carbonton Dam – Deep River Restoration Site. Restoration Plan. Project No. 05‐235. Accessed May 17, 2017. https://ncdenr.s3.amazonaws.com/s3fs‐ public/Mitigation%20Services/GIS_DATA/CarbontonDam_92268_MP_2005.pdf Restoration Systems, LLC. 2010. Carbonton Dam – Deep River Watershed Restoration Site 2010 Annual Monitoring Report (Year 5). NCDMS Project No. D‐04012A. Accessed May 17, 2017. https://ncdenr.s3.amazonaws.com/s3fs‐ public/Mitigation%20Services/GIS_DATA/Carbonton%20Dam_92268_%20MY5_2010.pdf USFWS (U.S. Fish and Wildlife Service). 1988. Cape Fear shiner recovery plan. USFWS, Atlanta. Wildman, Laura A.S. and James G. MacBroom. 2005. The evolution of gravel bed channels after dam removal: Case study of the Anaconda and Union City Dam Removals. Geomorphology 71. pp. 245‐ 262. Note: Previous correspondence with the USFWS and NCWRC are located in Appendix D. These communications took place when this project was being pursued as a mitigation bank, and therefore, all aspects may not be relevant to the current project. However, they do discuss the requirement for this Biological Assessment and associated Section 7 consultation with USFWS as well as the requirement for a Tier 1 evaluation and acceptance of the Tier 1 evaluation.

VI. List of Appendices Appendix A: Site Photographs Appendix B: Dewatering Plan and Corresponding Communications Appendix C: Sediment Management Plan and Corresponding Communications Appendix D: USFWS and NCWRC communications

.! Dam Location 8-Digit HUC

03030002

03020201

Rocky River

Jordan Lake

Dam .! Location Harris 03030003 Lake

Deep River

03030004

03040104

03040203

Figure 1 Vicinity Map 0 5 10 Miles Hoosier Dam Removal Project ¹ Biological Assessment Chatham County, NC Start of Impoundment 0#

Historic Dam Woody Dam Road

Hoosier Dam .!

Pittsboro 7.5' Minute USGS Topographic Quadrangle

Figure 2 Location Map Hoosier Dam Mitigation Bank 0 750 1,500 Feet ¹ Prospectus Chatham County, NC Cape Fear Shiner Designated Critical Habitat Impoundment Boundary Natural Heritage Element Occurances Significant Natural Heritage Areas Bear Creek (Chatham) Aquatic Habitat Lower Rocky River/Lower Deep River Aquatic Habitat Upper Rocky River Aquatic Habitat

Rocky River

Start of Impoundment

Reeves Lake

Hoosier Dam

2011 Aerial Photography

Figure 3 Critical Habitat Areas 0 1 2 Miles Hoosier Dam Removal Project ¹ Biological Assessment Chatham County, NC Project Area Impacted Area Impoundment Boundary Start of Impoundment Inundated Perennial Streams

Hoosier Dam

2013 Aerial Photography

Figure 4 Area Impacted by Project Hoosier Dam Removal Project 0 750 1,500 Feet ¹ Biological Assessment Chatham County, NC Appendix A Site Photographs

Photo 1: Hoosier Dam facing Upstream

Photo 2: Hoosier Dam Powerhouse Access Photo 3: Rocky River Impoundment at Powerhouse

Hoosier Dam Removal Project Appendix A Existing Conditions Photos

Photo 4: Rocky River Impoundment (Reeves Lake)

Photo 5: Upstream Extents of Impoundment

Hoosier Dam Removal Project Appendix A Existing Conditions Photos

Photo 6: Upstream of Impoundment. Critical Habitat Area for Cape Fear shiner

Photo 7: Downstream of Impoundment. Critical Habitat Area for Cape Fear shiner

Hoosier Dam Removal Project Appendix A Existing Conditions Photos Appendix B Dewatering Plan

Dewatering Plan for Reeves Lake Hoosier/Woody Dam, Rocky River Chatham Co, North Carolina USACE Action ID# SAW-2017-00511 NFWF Project ID #8020.16.054047

Prepared for: USACE NCDWR USFWS NCWRC

Submitted by: Unique Places, LLC Chris Flowers PO Box 52357 Durham, NC 27717 919.724.0676 (cell) [email protected] uniqueplacesllc.com

May 31, 2017

TABLE OF CONTENTS

Page

Section 1: Purpose ...... 1 Section: 2 Site Description ...... 1 2.1 Site Location ...... 1 2.2 History ...... 1 Section 3: Methods ...... 2 3.1 Procedure ...... 2 3.2 Environmental Measures ...... 3 3.3 Mussel Salvage Plan ...... 4 Section 4: Timing ...... 4 Section 5: Regulatory ...... 5 Section 6: Next Steps ...... 5 Site Photos...... A1 Memorandums ...... B1

SECTION 1 PURPOSE

1 Purpose

On behalf of the dam property owner, Rocky River Hydro LLC, we request concurrence with the proposed drawdown procedure described herein for lowering Reeves Lake. The purpose of the drawdown is to facilitate a sampling of the accumulated sediment wedge upstream of the dam and to stabilize streambanks upstream of the dam prior to demolition. Longer term plans are being made to remove the dam and power house entirely and the drawdown/sediment sampling is the next step in the critical path to completing the necessary engineering and design associated with the dam removal. Sediment sampling and removal will be accomplished following the completion of the drawdown. Following the drawdown, it is our intention to leave the lake in the dewatered state until the time of dam removal, which is expected to occur in late summer 2017.

SECTION 2 SITE DESCRIPTION

2.1 Site Location

Dam location: The site (35° 38’ 08”N, 79° 12’ 40”W) is located in Chatham County, along N.C. Highway 87 approximately six miles south of the of the Town of Pittsboro, North Carolina. The subject site is located on the Rocky River approximately 5 ½ miles upstream of its confluence with the Deep River (HUC 03030003). To access the site from Raleigh, drive south on US-1S for approximately 31 miles. Exit onto NC-87N/US-15N/US-501N/Hawkins Ave and drive north for approximately 6.1 miles. Turn left onto Walter Bright Road and proceed west for approximately 0.5 miles. Turn right to stay on Walter Bright Road and proceed west for another 0.6 miles. Turn right onto Asbury Church Road and proceed north for approximately 0.6 miles. Turn left onto Mays Chapel Road and proceed north for approximately 1.0 mile. Turn right onto Woody Dam road and proceed for approximately 0.5 miles to the dam site on the right.

2.2 History

Dam History: Hoosier Dam is a concrete buttress dam with an attached hydroelectric powerhouse. The dam was built in 1922, and is constructed of reinforced concrete, with a total length (including the powerhouse), of 235 feet and an average structural height of 25 feet. The hydroelectric facility

at Hoosier Dam contains three turbines that were operated by Hoosier Hydroelectric, Inc. as a small renewable energy producer. In October, 2012, the renewable energy contract with Progress Energy Carolinas was terminated, and in 2013 a new contract between Rocky River Hydro LLC (the current owner) and Duke Energy Progress was established. The dam can continue to be operated as a hydroelectric facility until removal.

SECTION 3 METHODS

3.1 Procedure

Dewatering of Reeves Lake will follow the same process used when the lake was dewatered 20 years ago. It will be completed by locking the turbine in place and opening the existing turbine control gates, also known as wicket gates, within the brick power generation facility of the dam. Water flows will discharge through the gates directly into the Rocky River at the base of the facility. Gate opening dimensions have been measured to facilitate the calculation of a target flow rate that will draw down the lake at a rate of approximately one foot of elevation per day. This translates to approximately 50cfs above normal baseflow. Refer to pg. 2 of attached Lake Drawdown Memorandum for extrapolated monthly baseflows at Hoosier Dam (Schnabel Engineering, February 8, 2017). The wicket gates will be opened incrementally to achieve the targeted flow rate. Given the depth of the lake, drawdown will be completed over 25 to 40 days, allowing for variability in flow volumes coming to the gate openings. An existing water level gauge located in the power house will be utilized to measure the rate of drawdown. The gauge will be checked daily and flow will be adjusted as necessary achieve the targeted drawdown rate of 1’/day. Existing gauge date, such as the USGS gauge in Siler City, will be referenced to anticipate flows. Operators, through the manipulation of the wicket and flap gates, will attempt to mimic natural flow patterns (rising and falling flows) during the dewatering process. Once the drawdown is complete all of the operable gates will be opened to allow inflows to pass through the dam. The right chamber floor drain has not been opened in 20+ years so the mechanical functionality of this gate is unknown. There is a possibility that it is inoperable. If gates break it is likely that gravity will cause the flap style gates to close flush against the floor of the chambers. In the unlikely scenario that gates break in the open position, and there is a need to stop flow during dewatering,

the turbine casings can be manually plugged. More detailed information regarding the dewatering process can be found in the attached Lake Drawdown memorandum (Schnabel Engineering, February 8, 2017). Additionally, a description of the power facility turbine and gates can be found in the attached Gate Functions memorandum (Schnabel Engineering, March 20, 2017).

3.2 Environmental Measures

During drawdown, the dewatered land will be seeded with millet on a weekly basis. It will also be inspected for major erosional areas which will be managed on a case by case basis using soft stabilization measures (silt fencing, coir matting, coir logs, plantings, additional seeding, etc.). A more robust planting regime will be implemented during the river restoration effort post-dam removal.

Turbidity monitoring will be conducted daily during the drawdown period and will commence two weeks before drawdown and extend two weeks following the completion of the dewatering. The turbidity sampling point will be located approximately 100’ downstream of the power facility on the right bank. An additional turbidity measurement within the lake will also be taken on a weekly interval, which will be sampled from the catwalk attached to the power house. Based on feedback from NCWRC and USFWS a maximum threshold of 50 NTUs will be adhered to during the dewatering process. It is understood that mussels can tolerate short term spikes in turbidity and that it may be advisable in a high turbidity event to maintain open flow conditions (i.e. not mechanically reduce flow). If turbidity approaches the 50 NTU threshold UP staff will immediately contact the NC Wildlife Resource Commission (NCWRC) and United States Fish and Wildlife Service (USFWS) staff to discuss the situation. An action plan will be developed with NCWRC and USFWS and formalized based upon current river conditions, expected rain falls, gauge station data, etc. The prescribed actions to adjust flow (if any) will be implemented immediately by UP staff.

Generally, if turbidity levels are similar upstream and downstream, flow through Hoosier Dam will be maintained at a steady rate. If turbidity downstream of Hoosier Dam is significantly higher than turbidity upstream of the dam, suggesting a mobilization of sediment, flow through the dam will be gradually reduced (up to 50%) by manipulating the wicket gates and or closing flap gates.

On March 27th, 2017, UP staff pumped accumulated sediments out of the right turbine chamber in preparation for an inspection of the gates within the chamber. Utilizing a 3” trash pump running continually for several hours, accumulated sediments within the right chamber were greatly reduced. Sediments were pumped to a 2 stage check dam which clarified the returning water

which was routed back into Reeves Lake. Sediments were seeded in with annual rye and the check dams were allowed to remain in place to maximize sediment stability. The cleanout of the right turbine chamber will eliminate unnecessary sediment from entering the river when the right chamber gates are opened during the dewatering process (if they are needed).

3.3 Mussel Salvage Plan

During drawdown, there is a possibility that the currently inundated side slopes of the valley will be dewatered too rapidly for mussels within the reservoir to retreat into the lowered water levels. To ensure that the dewatering does not strand sensitive mussel species a mussel salvage plan has been created in association with the NCWRC. The NCWRC will accompany UP staff during the initial stages of dewatering to observe the changing habitat conditions and assess mussel quantities in the impoundment. The salvage plan in general includes walking the exposed land and collecting stranded mussels by hand and quickly relocating them back into the Rocky River in an area upstream or downstream of the lake. The relocation area(s) will be specified by the NCWRC in the field. Necessary collection permits including a Scientific Collection Permit and a State Endangered Species Permit, specific to this project, will be obtained by UP staff prior to mussel salvage.

SECTION 4 TIMING

4 Schedule

Dewatering would ideally commence within the first two weeks of June 2017 which will maximize the effectiveness of the drawdown from a watershed hydrology perspective. The lowest monthly baseflows are in June, July, and August with extrapolated flow volumes of 90.6 cfs, 88.1 cfs, and 66.1 cfs, respectively. Refer to pg. 2 of attached Lake Drawdown Memorandum for extrapolated monthly baseflows at Hoosier Dam (Schnabel Engineering, February 8, 2017). This time frame is also ideal for aquatic species including mussels and Cape Fear Shiner by avoiding spawning and reproductive windows.

SECTION 5 REGULATORY

5 Regulatory Concurrence

Confirmation of regulatory requirements, or lack thereof, to dewater Reeves Lake per the above procedure will be obtained from the US Army Corps of Engineers (USACE) and NC Division of Water Resources (NCDWR) prior to initiating dewatering. Additionally, concurrence will also be obtained from USFWS, NCWRC, and the Federal Energy Regulatory Commission (FERC). All the above agencies are aware of the project, its objectives, and have provided feedback that has shaped the process described in this document.

SECTION 6 NEXT STEPS

6 Next Steps

Prior to initiating dewatering by the methods described herein, we desire concurrence regarding the dewatering process from the regulatory agencies listed in Section 5. Following regulatory concurrence, UP will propose a dewatering start date to these regulatory agencies. Dewatering will be initiated in the field on the approved start date by UP staff, NCWRC representatives, and likely others.

APPENDIX A SITE PHOTOS

Hoosier Dam

A-1

Power House

Turbine, wheel operates wicket gates

A-2

Left chamber 12” floor drain (at jack) and Turbine.

Power House

A-3

APPENDIX B MEMORANDUMS

B-1

SCHNABEL ENGINEERING SOUTH, P.C. 11A Oak Branch Drive Greensboro, NC 27407 T/ 336-274-9456 F/ 336-274-9486

MEMORANDUM

TO: Ms. Angela Allen, PE DATE: February 8, 2016

COMPANY: Wildlands Engineering, Inc SUBJECT: Lake Drawdown At Rocky River Dam ADDRESS: 312 West Millbrook Road, Suite 225 PROJECT 17C21002.00 Raleigh, NC 27609 NAME/NO.: Rocky River Dam Removal FROM: Maridee Romero-Graves, PE CC: John Hutton

INTRODUCTION

In support of an initial drawdown of the reservoir impounded by Rocky River Dam (also known as Hoosier Dam), a hydrology and hydraulic analysis was performed to determine reservoir drawdown rates for lowering pool elevations as a first phase for removal of the dam. The analysis was completed using the US Army Corps Hydrologic Model system (HEC-HMS). The HEC-HMS model was developed to estimate the hydraulic capacity of the dam hydraulic components and their ability to lower the pool elevation of the lake. It included a tailwater rating curve based upon a Rocky River HEC- RAS model obtained from Angela Allen with Wildlands Engineering, Inc. on January 16, 2017. The goal is to lower the lake at approximately 1 ft per day.

This memorandum summarizes the results of the estimated drawdown capacity for the existing powerhouse gates and turbines at Rocky River Hydroelectric Dam (Hoosier Dam) to support the removal of the concrete dam structure.

Limited data was used for the hydrology and hydraulic analysis presented in this memo. Some of the limitation/assumptions encounter during the analysis includes:  The bathymetry for Rocky River did not extend upstream enough to have a more accurate stage storage curve.  LiDAR data was not able to be use for stage storage since the contours near the water line were affected by the water pool of the reservoir.  USGS topography was used to manually estimate the stage storage above normal pool.  There was very limited information available for the turbine located in one of the bays of the powerhouse. A rating curve for the turbine was developed by using the dimensions of the wicket gates provided by the dam operator and field measurements. According to the calculations, it appears as the opening of the turbine funnel (~24- inches in diameter) controls the dewatering flow through the turbine.  It was assumed that the two 12-inch orifices in the powerhouse bay were round, with the same invert elevation and location as the 24-inch orifice. In other words, the two 12-inch orifices were assumed round, horizontal and with inverts at El 288.  A stream gage upstream of Rocky River Dam was used to determine the baseflow at the dam by using a ratio of the watersheds. The stream gage upstream of the dam presented twenty seven years of data.  No curve number and lag time was determined since at this point in the project, no runoff analysis for various storm scenarios is required.

SENT VIA: First Class Mail Overnight Service Email Other

G:\2017\GREENSBORO\17C21002_00_ROCKY_RIVER_DAM_REMOVAL\03-SE PRODUCTS\03-REPORTS\02-FINAL\HYDRAULIC MEMORANDUM\RR_HH_FEB20 2017.DOCX Wildlands Engineering, Inc Rocky River Dam Removal

 The HEC-RAS model provided by Wildlands Engineering, Inc. was used to generate a tailwater curve.

HYDROLOGY

Watershed

The watershed drainage area for Rocky River Hydroelectric Dam was delineated in Arc-GIS using USGS Topography Maps. Based on this delineation, the contributing drainage area is approximately 181.6 square miles. The watershed delineation map is attached to this document.

Base Flows

The nearest stream gage that could be used to estimate base flows to Rocky River at the dam location is located 31 stream miles upstream of the dam (USGS 0210166029 Rocky River at SR 1300). This stream gage covers a watershed area of 7.42 square miles with a data record from 1988 to 2015. The mean monthly discharge for each month was estimated from this record, and then adjusted to mean monthly baseflows at Rocky River Hydroelectric Dam by using a watershed ratio. The table below shows the mean monthly discharges at the USGS stream gage number 0210166029 and the adjusted mean monthly discharges estimated for Rocky River Dam.

Table 1: Mean Monthly Flows at Gage Number 0210166029 and the Extrapolated Values at Rocky River Hydroelectric Dam USGS Gage Rocky River Location 0210166029 Dam Watershed Area (sq.mi) 7.42 181.6 January 10 244.7 February 11 269.2 March 15 367.1 April 9.1 222.7 May 4.5 110.1 Monthly Mean June 3.7 90.6 Flows July 3.6 88.1 (cfs) August 2.7 66.1 September 4.2 102.8 October 4.3 105.2 November 6.1 149.3 December 7.7 188.5

Baseflows are estimated to be highest during the months of January through April, with the mean peak occurring in March. The lowest base flow values are estimated to occur in summer, with lowest mean flows occurring in August. (See USGS stream gage data attached to this document).

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Stage Storage

The stage storage curve for Rocky River Lake was estimated from a bathymetric survey performed by Infinite Land Design, P.C. on June 19, 2015. This survey does not include the entire Lake. Stage-storage information above normal pool was estimated using USGS Topographic Maps. However, due to incomplete topographic information, this is a preliminary stage-storage curve with some uncertainty, and may merit refinement as this projects moves forward.

HYDRAULICS

Hydraulic Components

The run-of-river spillway is 216 feet long with the crest at El 302.4. The powerhouse is located near the dam right abutment and contains two bays, one with a turbine (reportedly 1.55MW) and the other is empty where a second turbine could have been installed. Currently, we do not have information about the turbine except that it has fourteen wicket gates that could be operated for the lake drawdown operations. According to the dam operator, the wicket gates are 13.5 inches tall with 8 inches in between wicket gates when fully opened. The funnel diameter of the turbine appears to be 24- inches in diameter. According to the dam operator, the opening in the floor of the second bay is 24-inches in diameter and each bay has also a 12-inch opening.

No manufacturer information was provided for the turbine, including hydraulic rating curves. A preliminary rating curve for the openings of the wicket gates/ 24” diameter funnel exit, for the 24-inch power house bay orifice and the two 12-inch orifices was developed in excel. We estimate that the hydraulic control of the turbine system is at the 24-inch funnel immediately downstream of the turbine. No hydraulic information (invert elevation, location, shape, etc) was provided for the two 12-inch openings located in each of the bays. For hydraulic calculation purposes, it was assumed that the two 12- inch orifice are circular located at the same crest of the 24-inch orifice (El. 288). The rating curves for both bays were added to the HEC-HMS model to estimate drawdown.

Tailwater Curve

The presence of tailwater could potentially reduce discharge capacity of the turbine and orifice in the empty bay. A tailwater rating curve was estimated using the HEC-RAS model for the portion of the Rocky River, downstream of the dam (obtained from Wildlands Engineering, Inc). The HEC-RAS model includes three scenarios, one for the existing conditions, one corresponding to the corrected conditions, and one for proposed conditions (dam removed). The corrected conditions model was used as the basis for the tailwater computations for the reservoir drawdown. The tailwater model was analyzed as a steady state flow analysis based upon a range of peak flows. The water surface elevation at the cross section immediately downstream of the dam (XS 30802.4) for the different flows was used as the tailwater curve for the HEC-HMS model described below. Table 2 shows the tailwater curve generated in HEC-RAS and included in the HEC-HMS model.

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Table 2: Spillway Outflow Vs Tailwater Elevation

Flow Tailwater Elevation (CFS) (ft) 5 271.98 25 272.04 30 272.15 40 272.44 50 272.58 60 272.72 70 272.81 80 272.9 90 272.97 100 273.04 150 273.36 200 273.52 230 273.6 240 273.63 250 273.66 5000 282.13

HEC-HMS Model

The U.S. Army Corps of Engineers HEC-HMS computer program, version 4.0, was used to estimate the hydrology and hydraulics of Rocky River Dam and watershed. The watershed area, mean monthly base flows and the stage storage previously described were included in the model. The lag time and curve number would need to be estimated if precipitation analysis is necessary for future design.

The existing overflow spillway and water conveyance through the power house was modeled in HEC-HMS . The overflow spillway section was modeled as a broad-crested spillway with the crest at El 302.4, weir length of 216 feet and weir coefficient of 2.68 ft^0.5/s. The turbine, 24-in orifice and the two 12-inch orifices in the power house were included as the rating curves previously mentioned. The model was then use to determine the rate at which the reservoir will drain by using the turbine or the 24-inch orifice or the combination of these two plus the two-12-inch orifices. Other scenarios evaluated included enlarging the 24-inch orifice to 48-inches or 60-inches and possible using it in combination with the turbine.

HEC-HMS results indicate that the 24-inch opening has the capacity to pass a maximum flow of about 78 cfs, with discharges slowly decreasing as the lake is lowered. As shown, drawdown is influenced by the estimated mean monthly baseflow; it may be difficult to lower the pool when baseflows are high. Tables 3 show the rate at which drawdown occurs depending on the month when operating the 24-inch orifice only.

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Table 3: Maximum Drawdown Using the Existing 24-inch Orifice

Max. Water Min. Water Drawdown Time to reach Elevation Elevation* Drawdown During Mean Baseflow the Minimum the month of: (cfs) (ft) (ft) Rate Elevation (ft/day) (Days:Hours) January 244.7 302.8 302.4 inflow>outflow February 269.2 302.9 302.4 inflow>outflow March 367.1 303 302.4 inflow>outflow April 222.7 302.8 302.4 inflow>outflow May 110.1 302.5 302.4 inflow>outflow June 90.6 302.5 302.4 inflow>outflow July 88.1 302.5 302.4 inflow>outflow August 66.1 302.4 299 ~0.2 28D:8H September 102.8 302.5 302.4 inflow>outflow October 105.2 302.5 302.4 inflow>outflow November 149.3 302.6 303.4 inflow>outflow December 188.5 302.7 304.4 inflow>outflow

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HEC-HMS results also indicate that the 24-inch opening and the turbine has the capacity to pass a combined maximum flow of 160 cfs, with discharges slowly decreasing as the lake is lowered. As shown, drawdown is influenced by the estimated mean monthly baseflow; it may be difficult to lower the pool when baseflows are high. Tables 4 and 5 shows the rate at which drawdown occurs depending on the month.

Table 4: Maximum Drawdown Using the Existing Turbine and 24-inch Orifice Time to reach Drawdown Mean Max. Water Min. Water Drawdown the Minimum During the Baseflow Elevation Elevation* Rate Elevation month of: (cfs) (ft) (ft) (ft/day) (Days:Hours January 244.7 302.7 302.4 Inflow>Outflow February 269.2 302.7 302.4 Inflow>Outflow March 367.1 302.9 302.4 Inflow>Outflow April 222.7 302.6 302.4 Inflow>Outflow May 110.1 302.4 295.5 ~0.7 10D:17H June 90.6 302.4 293.1 ~1.2 5D:12H July 88.1 302.4 292.8 ~1.3 5D:7H August 66.1 302.4 290.7 ~1.7 3D:19H September 102.8 302.4 294.5 ~1.0 7D:17H October 105.2 302.4 294.8 ~0.9 8D:10H November 149.3 302.4 301.7 ~0.1 22D:10H December 188.5 302.6 302.4 Inflow>Outflow

*until flow capacity of turbine plus 24” orifice = baseflow

Table 5: Maximum Outflows During the Drawdown at Rocky River Mean Max. Max. Max. 24” Total Max. Drawdown Monthly Overflow Turbine Orifice Peak Drawdown During the Baseflow Spillway Outflow Outflow Outflow Rate (ft/day) month of: (cfs) (cfs) (cfs) (cfs) (cfs) January 244.7 90.1 77.3 77.3 244.7 Inflow=Outflow February 269.2 114.4 77.4 77.4 269.2 Inflow>Outflow March 367.1 211.4 77.9 77.9 367.1 Inflow>Outflow April 222.7 68.4 77.2 77.2 222.7 Inflow>Outflow May 110.1 0 76.5 76.5 153.8 ~0.7 June 90.6 0 76.5 76.5 153.0 ~1.2 July 88.1 0 76.5 76.5 153.0 ~1.3 August 66.1 0 76.5 76.5 153.0 ~1.7 September 102.8 0 76.5 76.5 153.0 ~1.0 October 105.2 0 76.5 76.5 153.0 ~0.9 November 149.3 0 76.5 76.5 153.0 ~0.1 December 188.5 34.6 76.9 76.9 188.5 Inflow>Outflow

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HEC-HMS results also indicate that the 24-inch opening, turbine and the two 12-inch openings has the capacity to pass a combined maximum flow of approximately 191 cfs, with discharges slowly decreasing as the lake is lowered. As shown, drawdown is influenced by the estimated mean monthly baseflow; it may be difficult to lower the pool when baseflows are high. Tables 6 and 7 shows the rate at which drawdown occurs depending on the month.

Table 6: Maximum Drawdown Using the Existing Turbine, 24-inch Orifice and the two 12-inch Orifices Time to reach Drawdown Mean Max. Water Min. Water Drawdown the Minimum During the Baseflow Elevation Elevation* Rate Elevation month of: (cfs) (ft) (ft) (ft/day) (Days:Hours January 244.7 302.6 302.4 Inflow>Outflow February 269.2 302.7 302.4 Inflow>Outflow March 367.1 302.9 302.4 Inflow>Outflow April 222.7 302.5 302.4 Inflow>Outflow May 110.1 302.4 292.8 ~1.5 4D:6H June 90.6 302.4 291.2 ~1.9 3D:12H July 88.1 302.4 291.1 ~2.0 3D:4H August 66.1 302.4 289.7 ~2.4 2D:16H September 102.8 302.4 292.2 ~1.7 3D:19H October 105.2 302.4 292.4 ~1.6 3D:22H November 149.3 302.4 296.8 ~0.8 13D:11H December 188.5 302.4 302 ~0.1 12D:5H

*until flow capacity of turbine plus 24” orifice = baseflow

Table 7: Maximum Outflows During the Drawdown at Rocky River Mean Max. Max. Max. 24” Max. 2-12” Total Max. Drawdown Monthly Overflow Turbine Orifice Orifice Peak Drawdown During the Baseflow Spillway Outflow Outflow Outflow Outflow Rate (ft/day) month of: (cfs) (cfs) (cfs) (cfs) (cfs) (cfs) January 244.7 52 77.2 77.2 38.6 244.7 Inflow=Outflow February 269.2 76.1 77.2 77.2 38.6 269.2 Inflow>Outflow March 367.1 172.8 77.7 77.7 38.9 367.1 Inflow>Outflow April 222.7 30.4 76.5 76.5 38.5 222.7 Inflow>Outflow May 110.1 0 76.5 76.5 38.3 191.3 4D:6H June 90.6 0 76.5 76.5 38.3 191.3 3D:12H July 88.1 0 76.5 76.5 38.3 191.3 3D:4H August 66.1 0 76.5 76.5 38.3 191.3 2D:16H September 102.8 0 76.5 76.5 38.3 191.3 3D:19H October 105.2 0 76.5 76.5 38.3 191.3 3D:22H November 149.3 0 76.5 76.5 38.3 191.3 13D:11H December 188.5 0 76.5 76.5 38.3 191.3 12D:5H

Project 17C21002.00/ February 8, 2017 Page 7 Schnabel Engineering South, P.C. Wildlands Engineering, Inc Rocky River Dam Removal

The third scenario was also modeled in HEC-HMS. In this scenario we increased the diameter of the 24-inch orifice to 48- inches. Outputs from HEC-HMS shows that the maximum outflow from the 48-inches orifice is about 300 cfs. Table 8 summarizes drawdown for this scenario.

Table 8: Maximum Drawdown Using a 48-inch Orifice Only

Max. Water Min. Water Time to reach * Drawdown Drawdown Mean Elevation Elevation the Minimum During the Baseflow Flow (cfs) Elevation month of: (cfs) (ft) (ft) Rate (ft/day) (Days:Hours January 244.7 302.4 297.2 ~1.1 306.1 9D:12H February 269.2 302.4 299.1 ~0.7 306.1 13D:2H March 367.1 302.6 302.4 inflow>outflow 367.1 April 222.7 302.4 295.6 ~1.5 306.1 6D:2H May 110.1 302.4 290 ~4.8 306.1 1D:15H June 90.6 302.4 289.7 ~5.5 306.1 1D:10H July 88.1 302.4 289.7 ~5.6 306.1 1D:9H August 66.1 302.4 289.4 ~6.4 306.1 1D:5H September 102.8 302.4 289.9 ~5.1 306.1 1D:12H October 105.2 302.4 289.9 ~5.0 306.1 1D:13H November 149.3 302.4 291.4 ~3.4 306.1 2D:5H December 188.5 302.4 293.5 ~2.2 306.1 3D:0H

The fourth scenario was also modeled in HEC-HMS. In this scenario we increased the diameter of the 24-inch orifice to 48-inches and used it in combination to the turbine for drawdown. Outputs from HEC-HMS shows that the maximum outflow from the turbine during drawdown is about 77 cfs while the 48-inches orifice may pass about 300 cfs. Using this combination for drawdown we increased the flow capacity to a total of about 380 cfs. Table 9 summarizes drawdown for this scenario.

Project 17C21002.00/ February 8, 2017 Page 8 Schnabel Engineering South, P.C. Wildlands Engineering, Inc Rocky River Dam Removal

Table 9: Maximum Drawdown Using the Existing Turbine and a 48-inch Orifice Time to reach Drawdown Mean Max. Water Min. Water Drawdown the Minimum During the Baseflow Elevation Elevation* Rate Elevation month of: (cfs) (ft) (ft) (ft/day) (D:H) January 244.7 302.4 293.9 ~2.6 2D:16H February 269.2 302.4 295.1 ~2.0 3D:21H March 367.1 302.4 301.3 ~0.3 8D:16H: April 222.7 302.4 292.9 ~3.3 2D:5H May 110.1 302.4 289.7 ~11.6 1D:3H June 90.6 302.4 289.4 ~12.9 1D:1H July 88.1 302.4 289.4 ~13.0 1D:0H August 66.1 302.4 289.1 ~13.3 0D:22H September 102.8 302.4 289.6 ~12.8 1D:1H October 105.2 302.4 289.6 ~12.4 1D:2H November 149.3 302.4 290.3 ~12.1 1D:8H December 188.5 302.4 291.5 ~10.9 1D:18H

Lastly, a scenario was modeled in HEC-HMS where there is no baseflow. In this scenario, an orifice was sized so the rate of drawdown is 1-foot per day. It was estimated that the orifice to allow a drawdown of 1-foot/day needs to be approximately 19-inches in diameter and release a flow of approximately 50 cfs.

SUMMARY

The results of our analysis indicated that without accounting for baseflow, the required flow rate necessary to drawdown the lake at 1-foot per day is about 50 cfs. The 24-inch orifice and the turbine has a maximum flow capacity of about 80 cfs each. However, this flow corresponds to a reservoir elevation at normal pool and would decrease as the pool lowers. Using the 24-inch orifice, turbine and the two 12-inch orifices, the maximum flow capacity is 191 cfs.

The drawdown of the reservoir is impacted by the baseflow which fluctuates depending on the month of the year. We recommend to perform drawdown operations during the month of May through September. However, it is possible that drawdown operations can be performed during April by increasing the 24-inch orifice flow capacity. For example, drawdown during April might be accomplish by increasing the 24-inch orifice diameter to 48-inches or inclusive 60-inches.

In order to drawdown the reservoir at a rate of 1-foot/day (by using the turbine, 24-inch orifice, 48-inch orifice or any combination), we recommend controlling flows by operating the upstream gates.

SIGNED: Maridee Romero-Graves, PE

Project 17C21002.00/ February 8, 2017 Page 9 Schnabel Engineering South, P.C. Flap gate operating stem. Stem is raised or lowered to operate gate.

12” DIA Floor drain with flap gate.

Turbine-Left Bay Flap Valve for 12” DIA Floor Drain-Left Bay (Flap Valves for 24” DIA orifice and Turbine in left bay. 12” DIA floor drain located in right Wicket gates allow flow bay are similar) into turbine. Right bay has a 24” DIA orifice with a flap gate in the same location as the turbine.

Wicket gate operator stem. FLOW Headgate. Used for dewatering the bay for maintenance of components downstream of headgate. Left Bay Gates Headgate in right bay is similar; (view is from the powerhouse floor however is deteriorated to point looking down through the access it is no longer functional as a hatch into the dewatered bay) gate. Rocky River Dam Rock River Dam Gates Chatham County, NC

PROJECT NO. 17C21002.00

MEMORANDUM

TO: Ms. Angela Allen, PE DATE: March 20, 2016

COMPANY: Wildlands Engineering, Inc SUBJECT: Rocky River Gates Functions ADDRESS: 312 West Millbrook Road, Suite PROJECT 17C21002.00 225 Raleigh, NC 27609 NAME/NO.: Rocky River Dam Removal FROM: Robert Indri, PE CC:

Rocky River Gates Functions

Rocky River Hydroelectric Dam (Hoosier Dam) is a low hazard (according to NC Dam Safety), run of the river dam with a structural height of approximately 25 feet and a total length of 435 feet. The North Carolina ID number is CHATH-010 and the National Inventory of Dams number is NC00623. The dam is located approximately five miles south of Pittsboro, NC on the Rocky River. The majority of the dam structure consists of an un-controlled (no gates) concrete spillway. In addition to the concrete spillway, there is a powerhouse located near the right abutment of the dam. The powerhouse has two turbine bays, separated by a concrete wall. The left side turbine bay houses a Francis turbine. The right side turbine bay is configured similar to the left side turbine bay except a turbine was never installed.

Left Side Turbine Bay Gates:

The left side turbine bay contains three gates:  12-feet wide by 14-feet tall vertical lift head gate;  12-inch-diameter floor drain with flap gate; and,  Wicket gates on the turbine.

A 12-feet wide by 14-feet tall vertical-lift head gate is located on the upstream side of the left turbine bay just downstream of the trashrack. The function of the head gate is to allow de-watering of the turbine bay for maintenance of the turbine and associated items located in the turbine bay downstream of the head gate. A 12-inch-diameter floor drain with a flap valve (see Figure 1 for an example of a flap gate) is located downstream of the head gate. Its function is to drain leakage into the turbine bay while the bay is de-watered. The wicket gates are located on the turbine assembly (see Figure 2 for an example of wicket gates for a Kaplan Turbine). The function of the wicket gates is to allow water into the turbine to generate electricity. The wicket gates can also be used to drain the turbine bay when the head gate is closed.

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DOCUMENT2 Wildlands Engineering, Inc Rocky River Dam Removal

Figure 1: Example of a flap gate. The flap gates at Hoosier Dam are installed on a horizontal surface. With the flap gates installed in the horizontal position both gravity and water

pressure will want to force the gate closed.

Figure 2: Example of wicket gates for a Kaplan Turbine. Function and layout for a Francis Turbine (installed at Hoosier Dam) is similar

Project 17C21002.00/ March 20, 2017 Page 2 Schnabel Engineering South, P.C. Wildlands Engineering, Inc Rocky River Dam Removal

Right Side Turbine Bay Gates:

The right side turbine bay contains three gates:  12-feet wide by 14-feet tall head gate;  12-inch-diameter floor drain with flap gate; and,  24-inch diameter floor opening for installation of a turbine with a flap gate.

A 12-feet wide by 14-feet tall vertical-lift head gate is located on the upstream side of the right turbine bay just downstream of the trashrack. The function of the head gate is to allow de-watering of the turbine bay for maintenance of the turbine (if one was installed) and associated items located in the turbine bay downstream of the head gate. Since the turbine in the right bay was never installed, the head gate serves no operational function. The head gate has not been maintained and has deteriorated to the point that it is no longer functional as the gate i.e. it cannot hold back water. Similar to the left bay, a 12-inch-diameter floor drain with a flap valve is located downstream of the head gate. Its intended function is to drain leakage into the turbine bay while the bay is de-watered. A 24-inch-diameter orifice with a flap gate is located on the floor of the right turbine bay. The function of the orifice is for installation of a second turbine and the flap gate prevents water from flowing through the orifice without a turbine installed.

In the past, the gates through the powerhouse have been used as a low level outlet to drain the reservoir for maintenance activities. Since the discharge capacity of the gates through the powerhouse are small compared to inflows, draining the reservoir through the powerhouse can only be accomplished during the dry months of the year. The gates have not been used as part of the spillway system for passing inflows into the reservoir, and their capacity when compared to the capacity of the uncontrolled spillway is negligible. Gates

Project 17C21002.00/ March 20, 2017 Page 3 Schnabel Engineering South, P.C. Appendix C Sediment Management Plan And Corresponding Communication

Sediment Management Plan Hoosier Dam Removal Project Chatham County, NC

May 2017 Cape Fear River Basin

HUC 03030003

Prepared By: Prepared For: Wildlands Engineering, Inc US Fish and Wildlife Service 312 W. Millbrook Rd., Suite 225 551 Pylon Drive Raleigh, NC 27609 Raleigh, NC 27606 Phone: 919‐851‐9986 Phone: 919‐856‐4520

Contents Section 1: Introduction ...... 1 Section 2: Characterization of Sediment Wedge ...... 2 Section 3: Criterion for Sediment Removal Protocol ...... 2 Section 4: Sediment Management Protocol 1: Removal ...... 3 Section 5: Sediment Management Protocol 2: Sediment Pulsing ...... 4

FIGURE Pebble Count Locations

APPENDIX Sediment Samples

Hoosier Dam Removal Project Tier 1 Sediment Evaluation ii Section 1: Introduction

The Hoosier Dam is a 94‐year‐old hydroelectric dam located on the Rocky River 5 ½ miles upstream of its confluence with the Deep River in Chatham County, North Carolina. The dam is being proposed for removal as part of a National Fish and Wildlife Foundation grant to restore the Rocky River from its currently impounded state back to a free flowing (lotic) state. The removal of the Hoosier Dam will open up 18,138 linear feet of habitat between two critical habitat areas for the endangered Cape Fear shiner.

The impounded reach behind the Hoosier Dam, referred to as Reeves Lake, backwaters 16,060 linear feet within the Rocky River and 2,078 linear feet within its six perennial tributaries. There is a sediment wedge located in the impoundment spanning approximately 1,030 linear feet upstream of the dam and across the width of the channel.

A Tier 1 evaluation was performed to identify potential sources of pollution in and around Reeves Lake and determine the likelihood of contamination in the sediments stored behind the dam. The perimeter of evaluation was set at 1‐mile surrounding the Reeves Lake impoundment and extended upstream to Siler City in regards to direct discharge. The evaluation yielded no potential sources of contaminants within the 1‐mile radius of Reeves Lake. The only potential source beyond that is the wastewater treatment plant in Siler City, 18.3 miles upstream. There have been no reports of violations or spills from the treatment plant on record.

The Tier 1 evaluation also involved a determination of the volume and characteristics of the sediment wedge. A combination of a bathymetric survey and sediment probing revealed the sediment wedge has a mobile layer of fine material over a restrictive layer of harder material: likely a mixture of sand, gravel, and cobble that is characteristic of the Rocky River bed material. The total volume of the sediment wedge is estimated to be 15,600 CY with 6,500 CY making up the mobile layer.

US Fish and Wildlife Service (USFWS) determined that based on the results of the Teir 1 evaluation, there is little to no potential of contamination of the sediment behind the dam (see attached correspondence). However, due to the volume of sediment within the wedge and the volume of highly mobile sediment, a detailed sediment management plan is necessary. This document outlines two protocols for sediment management, based on results of a sediment wedge investigation to take place during dewatering of the impoundment. If the sediment wedge is comprised of primarily fine material that has the potential to impact downstream fish and macroinvertebrate habitats, sediment will be removed and placed in upland areas prior to dam removal. If the sediment wedge is comprised primarily of gravel material, the sediment will be pulsed downstream during dam removal.

Hoosier Dam Removal Project 1 Tier 1 Sediment Evaluation Section 2: Characterization of Sediment Wedge

The Tier 1 Sediment Evaluation, previously completed for this project, explained the detailed methods used to determine the quantity and location of the sediment wedge upstream of the Hoosier Dam. The sediment wedge starts approximately 1,000 feet upstream of the dam, peaking at 500 feet upstream of the dam and gradually decreasing in the downstream direction. The crest of the sediment wedge is at the approximate elevation of the invert of the wicket gates located on the powerhouse. This shape indicates that stormflows create a back eddy against the dam, churning up sediment within the wedge at the base of the dam, entraining it in the water column, and flushing it from the system. The approximate volume of sediment in the wedge is 15,600 CY.

Several methods were used in attempts to sample and characterize the texture of material in the sediment wedge (See Tier 1 Evaluation), however no method was able to penetrate more than a foot into the wedge. It was determined that the wedge is topped by a highly mobile silt/sand mixture of a few inches in depth, however, nothing is known of the underlying sediment matrix. Testing indicates it may be a coarser material consisting of sand, gravel, and cobbles. This would be consistent with the existing bed material within the Rocky River.

Several pebble counts were done up and downsteam of the impoundment to characterize the native bed material within the Rocky River and determine if bed composition changed upstream and downstream of the dam as a result of the dam impounding bedload (see Figure). It was determined that though the spread of size classes is similar, there is a component of gravel and cobble that is lacking downstream of the dam. This indicates release of some sediment downstream, should the wedge be comprised of gravels, would benefit the reach (sediment samples and pebble count data is located in the Appendix.

In order to apply an appropriate sediment management plan, that limits risk to downstream aquatic life, the composition of the sediment wedge needs to be properly characterized. The Reeves Lake impoundment is scheduled for dewatering in June of 2017. The impoundment will be dewatered through the existing powerhouse and the river will remain in free‐flowing condition until the dam is removed. The dewatering is described in more detail in the Dewatering Plan.

Once the impoundment is dewatered, there will be access to the sediment wedge from the banks of the Rocky River using small earthmoving equipment. Proper equipment will be mobilized to the site and used to take grab samples of the sediment wedge. This will be done in a few locations, as access and conditions allow. Grab samples will be used to characterize sediment size class at various depths in the sediment wedge.

Section 3: Criterion for Sediment Removal Protocol

After dewatering, Unique Places (project manager) and Wildlands Engineering (project engineer) will meet with USFWS, in consultation with the NC Wildlife Resource Commission (WRC), to discuss the results of the sediment wedge investigation. Concurrence will be reached with all groups involved before a management plan is chosen. If the sediment wedge is predominantly fine grained (Silt/Clay),

Hoosier Dam Removal Project 2 Sediment Management Plan then the sediment wedge will be removed from the Rocky River prior to full removal of the Dam. Protocol for this is discussed in Section 4 of this document. If the sediment wedge is predominantly coarse material (gravel/cobbles), then the sediment will be pulsed downstream during removal of the dam. Protocol for this is discussed in Section 5 of this document.

Section 4: Sediment Management Protocol 1: Removal

Should the sediment wedge be comprised of material that could deleteriously affect downstream aquatic life and habitat, the sediment wedge will be removed during construction activities. Dewatering will occur several weeks prior to construction, allowing access to the sediment wedge by mechanical equipment. Mechanical equipment will be used from the project banks to remove sediment from the channel cross‐section. A proposed longitudinal profile will be created for the river bed underneath the sediment wedge and through the dam cross‐section. This elevation will be at the estimated historic bed elevation. Sediment will be removed until the proposed bed elevation is reached, or stable bedforms comprised of bedrock, cobble, and gravel are exposed.

Sediment removed from the channel will be placed in an upland area on the project site outside of the limits of the regulated floodplain and any jurisdictional features. Sediment deposited in upland areas will be stabilized according to the North Carolina Department of Environmental Quality – Division of Energy, Mineral, and Land Resources (NCDEQ‐DEMLR) Erosion and Sediment Control Planning and Design Manual guidelines and in accordance with the Erosion and Sediment Control permit for the project.

The river banks and bed will be stabilized where sediment is removed using a combination of grade control structures, habitat structures, and bioengineering. River banks will be matted with biodegradable erosion control matting and seeded with temporary and permanent seeding. During the dormant season, banks will be planted with livestakes and other riparian species to improve bank stability and overall stream habitat conditions.

The site will be monitored throughout the construction process with the same protocols as those followed in the dewatering plan. Based on input from The NC Wildlife Resource Commission (NCWRC) and the US Fish and Wildlife Service (USFWS) a maximum threshold of 50 NTUs for turbidity will be adhered to during the construction process. Turbidity monitoring will occur daily during construction and extend two weeks following the completion of construction. The turbidity sampling point will be located approximately 100 feet downstream of the power facility on the right bank of the river. If turbidity approaches the 50 NTU threshold, active sediment removal will cease and Unique Places, LLC (UP) and/or Wildlands Engineering, Inc (Wildlands) staff will immediately contact the NCWRC and USFWS staff to discuss the situation. An action plan will be developed with NCWRC and USFWS and formalized based upon current river conditions, expected rain falls, gauge station data, etc. The prescribed actions will be implemented immediately by the Contractor.

Hoosier Dam Removal Project 3 Sediment Management Plan Section 5: Sediment Management Protocol 2: Sediment Pulsing

Should the sediment wedge be comprised of material that is not likely to impact downstream aquatic life and habitat, material from the sediment wedge will be pulsed downstream during and after construction. During dam removal, the dam will first be removed down to the elevation of the powerhouse’s wicket gate invert (approximately 14.5 vertical feet removed). This is the current elevation of the crest of the sediment wedge, and the elevation to which the impoundment will be dewatered prior to dam removal. After that point, the dam will be notched gradually over the course of one to two months to allow sediment within the wedge to mobilize and work its way through the system.

The turbidity monitoring protocol will be the same as discussed in Section 4. Adaptive management will be used, in consultation with USFWS and NCWRC, to determine if alterations in the dam removal sequence need to be made or changes need to be made in the notching intervals to maintain turbidity levels under 50 NTUs. Episodic events during construction temporarily increasing the turbidity is not a concern during this project, however sustained levels of increase turbidity would trigger adaptive management protocols.

Hoosier Dam Removal Project 4 Sediment Management Plan Limits of Reeves Lake Pebble Count Locations

XS1S1

Rocky River

XXSS22 XXSS33

XS4 Hoosier Dam

XS5 XS6

2011 Aerial Photography

Pebble Count Locations Hoosier Dam Removal Project 07501,500 Feet ¹ Sediment Management Plan Chatham County, NC Appendix Sediment Samples

Hoosier Dam Removal Project Sediment Management Plan Froehling & Robertson, Inc. GRAIN SIZE

R DISTRIBUTION

Project No: 66T-0132 Client: Wildlands Project: Hoosier Dam City/State:Chatam Co.

U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS HYDROMETER

6 4 3 2 1.5 1 3/4 1/23/8 3 4 6 810 1416 20 30 40 50 60 100140200 100 95 90 85 80 75 70 65 60 55 50

Percent Finer (By Weight) 45 40 35 30 25 20 15 10 5 0 100 10 1 0.1 0.01 0.001 Grain Size (mm) GRAVEL SAND COBBLES SILT OR CLAY coarse fine coarse medium fine

Sample No. Depth Classification LL PL PI Cc Cu 01 at 0.0 2.33 10.70 02 at 0.0 03 at 0.0 04 at 0.0 05 at 0.0 Sample No. Depth D100 D60 D30 D10 %Gravel %Sand %Silt %Clay 01 at 0.0 2 0.016 0.007 0.002 0.0 4.0 73.7 22.3 02 at 0.0 2 0.02 0.007 0.0 9.5 65.4 25.1 03 at 0.0 2 0.016 0.006 0.0 9.7 62.0 28.2 04 at 0.0 2 0.014 0.005 0.0 2.8 67.7 29.5 05 at 0.0 2 0.011 0.004 0.0 1.9 63.1 35.0 US_GRAIN_SIZE US_GRAIN_SIZE 66T-0132.GPJ F&R.GDT 8/10/15 Froehling & Robertson, Inc. GRAIN SIZE

R DISTRIBUTION

Project No: 66T-0132 Client: Wildlands Project: Hoosier Dam City/State: Chatam County, NC

U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS HYDROMETER

6 4 3 2 1.5 1 3/4 1/23/8 3 4 6 810 1416 20 30 40 50 60 100140200 100 95 90 85 80 75 70 65 60 55 50

Percent Finer (By Weight) 45 40 35 30 25 20 15 10 5 0 100 10 1 0.1 0.01 0.001 Grain Size (mm) GRAVEL SAND COBBLES SILT OR CLAY coarse fine coarse medium fine

Sample No. Depth Classification LL PL PI Cc Cu 06 at 0.0 07 at 0.0 08 at 0.0 0.41 110.53 09 at 0.0 10 at 0.0 Sample No. Depth D100 D60 D30 D10 %Gravel %Sand %Silt %Clay 06 at 0.0 2 0.012 0.004 0.0 8.1 56.6 35.3 07 at 0.0 2 0.015 0.004 0.0 19.6 47.4 33.0 08 at 0.0 2 0.267 0.016 0.002 0.0 55.3 28.4 16.3 09 at 0.0 2 0.005 0.0 2.5 37.9 59.6 10 at 0.0 9.5 0.007 0.002 0.4 2.3 45.1 52.2 US_GRAIN_SIZE US_GRAIN_SIZE 66T-0132.GPJ F&R.GDT 8/12/15 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 1

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 1 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 0 90 Gravel Cobble Boulder ND Medium 0.25 0.50 0 80 Bedrock SA Coarse 0.5 1.0 0 70 Very Coarse 1.0 2.0 5 5 5 60 Very Fine 2.0 2.8 5 50 Very Fine 2.8 4.0 5 Fine 4.0 5.6 3 3 8 40 Fine 5.6 8.0 4 4 11 30 L E Medium 8.0 11.0 6 6 17 20 V Percent Cumulative (%) Medium 11.0 16.0 4 4 21 GRA 10 Coarse 16.0 22.6 9 9 30 0 Coarse 22.6 32 5 5 34 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 5 5 39 Particle Class Size (mm) Very Coarse 45 64 4 4 43 Small 64 90 7 7 50 MY0‐09/2016 E Small 90 128 9 9 58 BL COB Large 128 180 9 9 67 Large 180 256 6 6 72 RockyRiver, Cross Section 1 Small 256 362 12 11 84 Individual Class Percent 100 R Small 362 512 6 6 90 LDE U Medium 512 1024 3 3 92 90 BO Large/Very Large 1024 2048 7 7 99 80 BEDROCK Bedrock 2048 >2048 1 1 100 70 Total 105 100 100 60 50 Cross Section 1 40 Channel materials (mm) 30 D16 = 10.32 20 D35 = 33.68 10 D50 = 91.8 Individual Class Percent 0 D84 = 366.2

D95 = 1344.5

D100 = >2048 Particle Class Size (mm)

MY0‐09/2016 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 2

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 2 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 1 1 1 90 Gravel Cobble Boulder ND Medium 0.25 0.50 3 3 4 80 Bedrock SA Coarse 0.5 1.0 6 6 10 70 Very Coarse 1.0 2.0 9 9 19 60 Very Fine 2.0 2.8 5 5 24 50 Very Fine 2.8 4.0 5 5 29 Fine 4.0 5.6 8 8 37 40 Fine 5.6 8.0 3 3 40 30 L E Medium 8.0 11.0 8 8 48 20 V Percent Cumulative (%) Medium 11.0 16.0 5 5 54 GRA 10 Coarse 16.0 22.6 4 4 58 0 Coarse 22.6 32 3 3 61 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 2 2 63 Particle Class Size (mm) Very Coarse 45 64 7 7 70 Small 64 90 6 6 76 MY0‐09/2016 E Small 90 128 3 3 79 BL COB Large 128 180 79 Large 180 256 5 5 84 RockyRiver, Cross Section 2 Small 256 362 6 6 90 Individual Class Percent 100 R Small 362 512 1 1 91 LDE U Medium 512 1024 3 3 94 90 BO Large/Very Large 1024 2048 94 80 BEDROCK Bedrock 2048 >2048 6 6 100 70 Total 99 100 100 60 50 Cross Section 2 40 Channel materials (mm) 30 D16 = 1.57 20 D35 = 5.07 10 D50 = 12.3 Individual Class Percent 0 D84 = 258.4

D95 = 2312.1

D100 = >2048 Particle Class Size (mm)

MY0‐09/2016 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 3

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 3 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 0 90 Gravel Cobble Boulder ND Medium 0.25 0.50 0 80 Bedrock SA Coarse 0.5 1.0 1 1 1 70 Very Coarse 1.0 2.0 8 8 9 60 Very Fine 2.0 2.8 5 5 14 50 Very Fine 2.8 4.0 10 10 24 Fine 4.0 5.6 5 5 29 40 Fine 5.6 8.0 5 5 34 30 L E Medium 8.0 11.0 4 4 38 20 V Percent Cumulative (%) Medium 11.0 16.0 6 6 44 GRA 10 Coarse 16.0 22.6 8 8 52 0 Coarse 22.6 32 4 4 56 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 3 3 59 Particle Class Size (mm) Very Coarse 45 64 7 7 66 Small 64 90 9 9 75 MY0‐09/2016 E Small 90 128 12 12 87 BL COB Large 128 180 8 8 95 Large 180 256 95 RockyRiver, Cross Section 3 Small 256 362 95 Individual Class Percent 100 R Small 362 512 5 5 100 LDE U Medium 512 1024 100 90 BO Large/Very Large 1024 2048 100 80 BEDROCK Bedrock 2048 >2048 100 70 Total 100 100 100 60 50 Cross Section 3 40 Channel materials (mm) 30 D16 = 3.01 20 D35 = 8.66 10 D50 = 20.7 Individual Class Percent 0 D84 = 117.2

D95 = 180.0

D100 = 512.0 Particle Class Size (mm)

MY0‐09/2016 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 4

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 4 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 0 90 Gravel Cobble Boulder ND Medium 0.25 0.50 0 80 Bedrock SA Coarse 0.5 1.0 3 3 3 70 Very Coarse 1.0 2.0 1 1 4 60 Very Fine 2.0 2.8 2 2 6 50 Very Fine 2.8 4.0 6 Fine 4.0 5.6 1 1 7 40 Fine 5.6 8.0 1 1 8 30 L E Medium 8.0 11.0 2 2 10 20 V Percent Cumulative (%) Medium 11.0 16.0 8 8 18 GRA 10 Coarse 16.0 22.6 6 6 24 0 Coarse 22.6 32 8 8 32 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 10 10 42 Particle Class Size (mm) Very Coarse 45 64 15 15 57 Small 64 90 12 12 69 MY0‐09/2016 E Small 90 128 7 7 76 BL COB Large 128 180 9 9 85 Large 180 256 1 1 86 RockyRiver, Cross Section 4 Small 256 362 3 3 89 Individual Class Percent 100 R Small 362 512 89 LDE U Medium 512 1024 89 90 BO Large/Very Large 1024 2048 5 5 94 80 BEDROCK Bedrock 2048 >2048 6 6 100 70 Total 100 100 100 60 50 Cross Section 4 40 Channel materials (mm) 30 D16 = 14.57 20 D35 = 35.45 10 D50 = 54.3 Individual Class Percent 0 D84 = 173.3

D95 = 2298.8

D100 = >2048 Particle Class Size (mm)

MY0‐09/2016 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 5

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 5 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 0 90 Gravel Cobble Boulder ND Medium 0.25 0.50 1 1 1 80 Bedrock SA Coarse 0.5 1.0 1 1 2 70 Very Coarse 1.0 2.0 2 60 Very Fine 2.0 2.8 2 50 Very Fine 2.8 4.0 2 Fine 4.0 5.6 4 4 6 40 Fine 5.6 8.0 6 6 12 30 L E Medium 8.0 11.0 6 6 18 20 V Percent Cumulative (%) Medium 11.0 16.0 8 8 26 GRA 10 Coarse 16.0 22.6 10 10 36 0 Coarse 22.6 32 5 5 41 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 9 9 50 Particle Class Size (mm) Very Coarse 45 64 10 10 60 Small 64 90 11 11 71 MY0‐09/2016 E Small 90 128 9 9 80 BL COB Large 128 180 6 6 86 Large 180 256 2 2 88 RockyRiver, Cross Section 5 Small 256 362 10 10 98 Individual Class Percent 100 R Small 362 512 2 2 100 LDE U Medium 512 1024 100 90 BO Large/Very Large 1024 2048 100 80 BEDROCK Bedrock 2048 >2048 100 70 Total 100 100 100 60 50 Cross Section 5 40 Channel materials (mm) 30 D16 = 9.89 20 D35 = 21.83 10 D50 = 45.0 Individual Class Percent 0 D84 = 160.7

D95 = 326.3

D100 = 512.0 Particle Class Size (mm)

MY0‐09/2016 Reachwide and Cross Section Pebble Count Plots Project Name (Hoosier Dam) Monitoring Year 0 ‐ 2016 RockyRiver, Cross Section 6

Diameter (mm) Summary Riffle 100‐ Particle Class Class Percent Count min max Percentage Cumulative RockyRiver, Cross Section 6 SILT/CLAY Silt/Clay 0.000 0.062 0 Pebble Count Particle Distribution 100 Very fine 0.062 0.125 0 Silt/Clay Sand Fine 0.125 0.250 0 90 Gravel Cobble Boulder ND Medium 0.25 0.50 0 80 Bedrock SA Coarse 0.5 1.0 1 1 1 70 Very Coarse 1.0 2.0 5 5 6 60 Very Fine 2.0 2.8 3 3 9 50 Very Fine 2.8 4.0 5 5 13 Fine 4.0 5.6 7 7 20 40 Fine 5.6 8.0 12 12 32 30 L E Medium 8.0 11.0 8 8 39 20 V Percent Cumulative (%) Medium 11.0 16.0 6 6 45 GRA 10 Coarse 16.0 22.6 4 4 49 0 Coarse 22.6 32 4 4 53 0.01 0.1 1 10 100 1000 10000 Very Coarse 32 45 4 4 57 Particle Class Size (mm) Very Coarse 45 64 6 6 63 Small 64 90 14 13 76 MY0‐09/2016 E Small 90 128 7 7 83 BL COB Large 128 180 4 4 87 Large 180 256 1 1 88 RockyRiver, Cross Section 6 Small 256 362 9 9 96 Individual Class Percent 100 R Small 362 512 96 LDE U Medium 512 1024 4 4 100 90 BO Large/Very Large 1024 2048 100 80 BEDROCK Bedrock 2048 >2048 100 70 Total 104 100 100 60 50 Cross Section 6 40 Channel materials (mm) 30 D16 = 4.54 20 D35 = 9.16 10 D50 = 24.7 Individual Class Percent 0 D84 = 143.7

D95 = 345.7

D100 = 1024.0 Particle Class Size (mm)

MY0‐09/2016 From: Wells, Emily To: Angela Allen Cc: John Hutton Subject: Re: Hoosier Dam Dewatering, USACE Action ID# SAW-2017-00511, NFWF Project ID #8020.16.054047 Date: Friday, May 26, 2017 3:11:32 PM

Hi Angela and John,

I ran your questions about the sediment management plan by Tom and he did not have any specific comments regarding the percentages of each category.

He didn't seem to think based on the previous data on sediment behind the dam, that there was going to be a lot of sediment that would potentially need moving, but agreed that analyzing it all once drawdown has occurred is the best way to approach which removal option would work best, if removal is needed at all. We can certainly chat more about it once we have the BA, and make edits as need be.

Thanks and have a good weekend, Emily

On Mon, May 15, 2017 at 2:54 PM, Angela Allen wrote:

Emily,

Do you have time in the next few days to chat about the sediment management plan we are including in the BA? John and I have been discussing what the threshold would be to determine if we will mechanically remove the sediment wedge prior to dam removal, or allow pulsing of material downstream. Our initial thought was no greater than 20% fines, and that the D50 channel material needed to be in the coarse gravel range. Obviously we will test based on depth to give us an overall look at stratification and translate that into volumes.

Do you have thoughts on this, or want to schedule a call to discuss?

Thanks,

Angela

From: Wells, Emily [mailto:[email protected]] Sent: Monday, May 15, 2017 11:03 AM To: Chris Flowers Cc: Angela Allen ; John Hutton

Subject: Re: Hoosier Dam Dewatering, USACE Action ID# SAW-2017-00511, NFWF Project ID #8020.16.054047

So they haven't answered the question yet as to whether the de-watering is part of their overall permit process? Sorry that is taking so long to get a response, since that meeting was in mid March! Hopefully you will get an answer soon.

~Emily

On Mon, May 15, 2017 at 10:54 AM, Chris Flowers wrote:

No update yet on the NWP permit review that the USACE is conducting. I will follow up again today. I'll keep you posted as soon as we get a response.

Thanks,

-Chris

On Fri, May 12, 2017 at 1:47 PM, Wells, Emily wrote:

Sounds great. Thanks!

~Emily

On Fri, May 12, 2017 at 1:42 PM, Angela Allen wrote:

Emily,

That works for us. We will have the BA to you by May 26th. The BA will include the Dewatering Plan and the Sediment Management Plan in the appendixes for reference. I will let you know if we have any questions as we proceed.

Thanks,

Angela From: Wells, Emily Sent: Thursday, May 11, 2017 11:42:21 AM To: Angela Allen Cc: Chris Flowers; John Hutton

Subject: Re: Hoosier Dam Dewatering, USACE Action ID# SAW-2017-00511, NFWF Project ID #8020.16.054047

Hey Angela,

I think it would be good to have it done before detwatering begins to cover any potential issues with sediment that makes its way downstream during that dewatering process. As long as the two (or more) options for sediment removal are clearly explained and we can address potential impacts with either one, then that should be sufficient to start the process. Based on the Tier 1 Sediment review, Tom did not have any major concerns with what appeared to be behind the dam in terms of quality or quantity of the material at that time. I think if there are major surprises when the sediment is exposed after dewatering we could re-consult on that particular topic due to new information being available, before moving forward to make sure everything has been covered adequately in the consultation. This way at least the majority of the document will be complete and you all would be covered during dewatering.

Let me know your thoughts on that route.

Thanks!

~Emily

On Wed, May 10, 2017 at 1:31 PM, Angela Allen wrote:

Emily,

It was my understanding that we needed to test the composition of the sediment wedge before the BA could be finalized (which would be after dewatering) since it may affect our sediment management plan. However, if we can complete the BA stating methods we would use if it’s fine sediment (removal) verses smaller amounts of coarse sediment (combo pulsing and removal likely), then that can greatly move up our timeline for completing the BA. Let me know if this is okay and I’ll get you a firm date on submission of the BA. I’m in the office the rest of the week if you’d like to call and discuss (919) 851-9986 x 106.

Thanks,

Angela

From: Wells, Emily [mailto:[email protected]] Sent: Monday, May 08, 2017 3:23 PM To: Chris Flowers ; Angela Allen ; John Hutton Subject: Re: Hoosier Dam Dewatering, USACE Action ID# SAW-2017-00511, NFWF Project ID #8020.16.054047

Hi Chris,

Thank you for the opportunity to review the dewatering plan. USFWS does not have any major questions or concerns with the proposed plan, and we (Sarah and I at least) will be as available as possible to assist with the pre-draw down and during the drawdown survey efforts. Below is some information that Mike Wicker provided, more of a FYI type of thing, but I wanted to pass it along.

Summer (Warm weather and low flow) vs Winter (cold weather and high flow) Draw downs in Preparation for Dam Removal

Summer draw downs

· better access to exposed sediments behind dam for mechanical removal

· draining and re-vegetation of exposed sediments is better in warm weather

· construction activities are easier in the summer - better weather

· generally more expensive because sediment removal can be very expensive

· engineered stream channel in old head pond post project- may look artificial

· aquatic surveys are easier (typical field season)

· better approach in situations where demolition involves sediment removal from behind dam because there is concern that the natural redistribution of sediment may cover mussel beds in the tail race area Winter drawn downs

· cool water can hold greater dissolved oxygen levels that can assimilate the release of sediment high in biological oxygen demand

· heavy rain events move sediment rapidly and naturally redistribute in the downstream channel giving a very natural result

· weather is not as suitable for heavy equipment and work may need to be postponed which can be expensive

· post project looks very natural - hard to tell where the dam was located

· less expensive because the stream is doing the work of sediment redistribution

· natural stream channel in old head pond post project vs engineered channel- looks better

· used where sand and gravel are seen as resource assets downstream rather than liabilities

· less expensive

· better approach if the system can handle the natural redistribution of sediment

Note: Winter draw downs have been used where there is a great concern over sediments and this approach basically sacrifices the short term (may lose a year class or suffer some mortality of adults in return for a natural stream channel post project. Basically a short term pain for long term gain approach.

On a separate note...is there any update on which permit the Corps will be requiring for this project? And do you all have an expected time frame for the BA to be ready for me to review. I am trying to make sure to allocate time for that on my calendar in the upcoming month or so as needed, but am going to be out of the office a good bit in May/June with field work and personal leave.

Thanks!

~Emily

On Thu, Apr 27, 2017 at 4:09 PM, Chris Flowers wrote:

All,

Please see the attached Dewatering Plan. This document takes into account the dewatering related protocols and elements that we discussed at our meeting on March 15, 2017. We would like to initiate Dewatering on June 1, 2017. Please review this plan and provide any feedback you may have. From the US Army Corps of Engineers and NC Divison of Water Quality personell I would ask that you confirm that Clean Water Act permits and/or water quality certifications are not required to initiate the dewatering process described in this document.

I appreciate your attention to this matter. Please reach out with any questions or comments.

Regards,

Chris Flowers Unique Places PO Box 52357 Durham, NC 27717 919.724.0676 (cell) [email protected] uniqueplacesllc.com

Emily Wells

USFWS Fish and Wildlife Biologist

Raleigh Ecological Services Field Office

551-F Pylon Drive

Raleigh, North Carolina 27606

Office # 919-856-4520 x25

Fax # 919-856-4556

Mailing Address: P.O. Box 33726

Raleigh, North Carolina 27636-3726

NOTE: This email correspondence and any attachments to and from this sender is subject to the Freedom of Information Act (FOIA) and may be disclosed to third parties.

Emily Wells

USFWS Fish and Wildlife Biologist

Raleigh Ecological Services Field Office

551-F Pylon Drive

Raleigh, North Carolina 27606

Office # 919-856-4520 x25

Fax # 919-856-4556

Mailing Address:

P.O. Box 33726

Raleigh, North Carolina 27636-3726

NOTE: This email correspondence and any attachments to and from this sender is subject to the Freedom of Information Act (FOIA) and may be disclosed to third parties.

Emily Wells

USFWS Fish and Wildlife Biologist

Raleigh Ecological Services Field Office

551-F Pylon Drive

Raleigh, North Carolina 27606

Office # 919-856-4520 x25

Fax # 919-856-4556

Mailing Address:

P.O. Box 33726

Raleigh, North Carolina 27636-3726

NOTE: This email correspondence and any attachments to and from this sender is subject to the Freedom of Information Act (FOIA) and may be disclosed to third parties.

Chris Flowers Unique Places PO Box 52357 Durham, NC 27717 919.724.0676 (cell) [email protected] uniqueplacesllc.com

Emily Wells

USFWS Fish and Wildlife Biologist

Raleigh Ecological Services Field Office

551-F Pylon Drive

Raleigh, North Carolina 27606

Office # 919-856-4520 x25

Fax # 919-856-4556

Mailing Address:

P.O. Box 33726

Raleigh, North Carolina 27636-3726

NOTE: This email correspondence and any attachments to and from this sender is subject to the Freedom of Information Act (FOIA) and may be disclosed to third parties.

-- Emily Wells USFWS Fish and Wildlife Biologist Raleigh Ecological Services Field Office 551-F Pylon Drive Raleigh, North Carolina 27606 Office # 919-856-4520 x25 Fax # 919-856-4556

Mailing Address: P.O. Box 33726 Raleigh, North Carolina 27636-3726

NOTE: This email correspondence and any attachments to and from this sender is subject to the Freedom of Information Appendix D USFWS Communication and Meeting Notes Topic: NFWF Kick Off Meeting with USFWS Date: August 29, 2016

Attendees/Role: Sara Ward USFWS services coordinator for the NFWF process. Contaminants Background. Dale Suiter USFWS plant background interested in Harperella restoration possibilities. Chris Flowers Unique Places Project Manager Jeff Fisher Unique Places CEO John Hutton Wildlands VP Angela Allen Wildlands Designer Emily Wells USFWS involved in the mitigation bank option Van Stancil NCWRC Mike Wicker USFWS experience is dam removal projects particularly demolition aspects. Sarah McRae USFWS Lead for Cape Fear Shiner Johnny Randall NC Botanical Garden harperella reintroduction into the deep river 2nd island funded by NFWF expertise in this area. Mike Kunz Botanical Garden -Harperella experience Trip Bolton fish passage, fish habitat coordination/maintenance

Jeff Unique Places role is to ● Manage the project ● Determine how to get the dam down in the most economic way ● Be a steward of Tim's interests ● Leverage the funds as far as possible to achieve the max conservation impact

Jeff mentioned that Tim Sweeney wants Deep to be a wild and scenic river. Brought up the possibility of taking an additional upstream dam out and potential grant funding to complete that work.

Jeff put forward the idea of an “executive team” that would consist of highly involved staff members from the represented agencies. It was essentially determined that staff will be involved as much as their time allows within their specific discipline.

3 goals for the meeting were put forth.

1. Next Step Set up a site visit. 2. Who is on the executive team. 3. How involved will the different agencies be in assisting with this project.

Project History: Provided by Wildlands (included site photographs) ● 25' tall, slab and buttress design, ● turbines can be released to draw water down. ● FERC license is already surrendered. ● as much as 15K cu of sediment accumulated upstream of the dam. ● Tier 1 analysis is complete and showing no risk of contaminants. ● John Alderman thought that the dam was a sink for contaminants. ● Wildlands collected water quality data to prove that it, if anything, it is actually a source though not statistically significant). Water Quality sampled during July and August. ● Wildlands looked for a depth of refusal in the sediment with probe rods. ● Impoundment is about 16,000 feet long.

Wetlands ● 404 and 401 permit will be required. ● USACE agent is now David Bailey (formerly Andy Williams) ● Approved WL JD is still needed. ● The question of a permit being required for dewatering came up with the specific context of the hydrologically dependent fringe wetlands around the impoundment. After much discussions it was largely agreed that up-front discussions with the USACE should happen as soon as practical. ● The project timeline will vary greatly depending on the 404 permit required (nationwide v. individual) ● This should be determined as soon as possible. ● The biological assessment will follow the same process as it would in the Mitigation Bank Scenario.

Sediment Analysis ● Wildlands has done a Tier 1 sediment report. Modeling has not been done yet. ● A Tier 2 analysis is not likely to be necessary due to the lack of contaminants

Species Issues ● USFWS suggests that there are some mussel issues downstream. ● USFWS needs mussel surveys done prior to leaf fall though a spring survey is fine if necessary. ● Sara McRae and NCWRC may be able to assist with the mussel survey though this is more likely for a spring survey than this fall. ● Shooting for demo by the end of next summer. ● Two questions came up regarding sediment that affect aquatic species. ○ How do we deal with sediment ○ When do we de-water relative to taking down the dam. ● Harperella Botanical Garden will need some lead time. they have some live populations and seed bank but will need a year to prepare for that. ● Mike at Botanical garden there is a lot of good habitat in the Deep. Would be interested in a survey of this reach. Too late this year. ● Unique places will pull the NHP data to determine what rare species are in the dataset for this reach. ● There is usually an invasive species removal component as part of the plan. ● Dewatering is not dependent on downstream mussel surveys, so long as turbidity does not create a problem. ● USFWS suggested that the restoration plans should show how the Cape Fear Shiner will reestablish into the reach (connectivity between the upper and lower populations). ● Atlantic Pigtoe and the Brook Floater are additional mussel species to consider. One (or both?) of these are expected to be listed early next year. One option would be to “assume” and impact and prepare a restoration plan. Mussels could be “grown” but will require significant time to produce a community suitable for restoration.

Construction ● Trip Bolton’s group can handle the construction and has experience in removing equivalent and larger dams. This would constitute a large cost savings to the budget which could be utilized for subsequent conservation efforts. ● Trip Bolton USFWS [email protected] ● 8438191229 will send us some info regarding dam removal. Can handle the Dam removal (construction). Fish Passage program is a 50/50 match.

<<<<<<<<<< NEXT STEPS >>>>>>>>>>>>>> Sediment Analysis UP wildlands have already scheduled Executive team site meeting UP will schedule this asap and will communicate the date to all. Mussel Survey downstream of the dam (Sarah McRae will confirm the length of survey reach needed) UP will send a letter to the IRT recipients to let them know the Mit bank is offline and the new objectives of the project. Loop Misty from NCNHP into this project. Gather additional budget information for Mussel Restoration Gather additional budget information for USFWS dam removal services (from Trip)

July 21, 2014

Mr. Andrew Williams U.S. Army Corps of Engineers Raleigh Regulatory Field Office 3331 Heritage Trade Drive, Suite 105 Wake Forest, NC 27587

Subject: Response to Public Notice Comments Hoosier Dam Mitigation Bank Wildlands Engineering Project No. 005‐14005

Dear Mr. Williams,

We have reviewed the comments from the public notice period for the Hoosier Dam Mitigation Bank dated June 5, 2014. Below are the responses to each of the regulatory agency comments. For your convenience, the comments are reprinted with our responses in italics.

Comments by Karen Higgins, NCDENR April 15, 2014

l. The majority of the proposed mitigation units (Table 3) are based on improving the water quality of the Rocky River and its tributaries. Monitoring (both pre‐ and post‐removal) should be performed to assess water quality and aquatic function of the impounded reaches and their post‐impoundment condition. Physicochemical monitoring should follow up on temperature and nutrient data collected and presented in the Prospectus.

Extensive baseline and post‐dam removal monitoring programs have been developed for the Hoosier Dam Mitigation Bank based on previous dam removal projects and input from the US Fish and Wildlife Service. A supplemental monitoring document has been attached, which will be included in the Final Mitigation Plan.

Water quality monitoring protocol and associated success criteria are located in Sections 2.1.2 and 2.2.4. Monitoring will be done seasonally each monitoring year at seven stations and include sampling of temperature and dissolved oxygen, as the goals of the project is to ameliorate temperature and dissolved oxygen stratification within the previously impounded sections of the Rocky River.

Biological monitoring should focus on improvement of water quality through conversion from a lentic to a lotic system. Parameters for monitoring should include macrobenthos and fish. Performance standards should be crafted to document improvements in physicochemical parameters and to the biotic community. Meeting each individual performance standard over the course of the monitoring period should have an associated percentage of the total water quality improvement credit.

Aquatic biological community sampling protocol and success criteria are described in Sections 2.1.4 and 2.2.2 in the attached supplemental monitoring document. Sampling will include macroinvertebrates, snails, mussels and fish surveys along with habitat evaluations at each sampling station.

Wildlands Engineering, Inc.  phone 919-851-9986  fax 919-851-9987  312 W Millbrook St Suite 225  Raleigh, NC 27609

DWR recommends consulting the Milburnie Dam Draft Mitigation Plan dated March, 2014 for an example of performance standards and associated credit yield. While the performance standards and credit yield presented in this plan may not be appropriate for the Hoosier Dam project, the concepts may provide useful in development the Hoosier Dam mitigation plan.

As the Milburnie Dam Draft Mitigation Plan is not an approved document it could not legally be made available to Wildlands. To mitigate this, Wildlands is consulting with the IRT agencies on aspects of the Milburnie plan they wish to include on this project.

2. The total proposed potential credit for the project raises a concern that has been the topic of discussions among the IRT in the past. Specifically, if it is appropriate for the DE to allow for more credit to be generated by a dam removal project than the amount of the mitigation that would be required if the dam was constructed now.

The mitigation plan (Table 3) indicates the total maximum potential credit for the project is 24,105 LF (24,105 credits). The impounded reach of the river and associated tributaries has been calculated to be 22,425 LF. If the project were proposed today, based on DE requirements on other impoundment projects, the mitigation required would likely be as follows:

Impact Type Impact Amt (LF) DA Multiplier Mitigation Requirement Fill (Dam Footprint) 200 Lf* 2:1 400 LF Inundation 22,225 LF 1:1 22,225 LF Total Mitigation Required 22,625 LF

*Approximate based on aerial photography

According to the proposed maximum potential credit from the mitigation plan, the Sponsor would potentially be awarded 1,480 more linear feet of credit (24,105‐22,625) than the mitigation that would potentially be required to permit the construction of the dam and impoundment of 22,425 LF of river and tributaries. As this issue has not been resolved, this should be discussed by the IRT at the next regularly scheduled meeting.

The additional credits requested by the Bank Sponsor reflect the proposal for the establishment of riparian buffer conservation easements along Rocky River and its tributaries as discussed in Section 3.2.4 of the Prospectus. The easements, on lands already purchased by the Sponsor, will protect over 35% of the riparian buffer along the Rocky River within the bank limits, 100% of the riparian buffer along Tributaries 3 and 4, and 33% along Tributary 2 (tributary credit will be requested only in cases where an easement can be recorded on both sides). Wildlands and the Bank Sponsor agree that the easements are important in protecting this water resource during its conversion from a lotic to lentic system and in perpetuity to protect Cape Fear shiner habitat.

The Bank Sponsor intends to protect the riparian buffers along their properties during their ownership of the lands, however, only a conservation easement will ensure permanent protection. The Sponsor requests compensation for easements in the form of Mitigation Credits. If no credits are awarded, easements will not be recorded on the Rocky River as proposed and the credit request will be altered.

3. Monitoring activities should also include stability monitoring of all formerly‐impounded tributaries proposed for credit. Lowering of the water level after dam removal has the potential to expose unvegetated streambanks, which could result in streambank erosion/headcutting. As described in the attached supplemental monitoring plan (Sections 2.1.1 and 2.2.1), geomorphic monitoring stations will be established on all tributaries where credits are requested, spaced 25 bankfull widths apart. These stations will be monitored directly after dewatering and then annually during the monitoring period.

4. The standard service area for mitigation banks in North Carolina is the eight‐digit HUC in which the bank is located. The location of the bank site at the southeastern end of 0303003 and its close proximity to 0303004 makes the proposed service area feasibly. DWR would support the primary service area for this bank to include all of 03030003 and the Piedmont portion of 0303004.

The proposal is to include only the Piedmont portion of 0303004 in the bank service area. This will be made clearer in the text and figures of the Mitigation Plan. Figure 3 from the Prospectus will be altered to highlight this distinction.

5. We strongly encourage the bank Sponsor to continue to acquire property along the Rocky River and associated bank tributaries, and inclusion of such lands within the bank conservation easement.

The Bank Sponsor continues to pursue the purchase of land along the impoundment of Reeves Lake. They have recently purchased two parcels along the right bank of the impoundment approximately 2,500 linear feet upstream of the dam and adjacent to previously purchased parcels. As long as mitigation credits will be awarded for conservation easements, as discussed in the response to above Question 2, they will be included in the Hoosier Dam Mitigation Bank.

Comments from Shari Bryant, NCWRC April 10, 2014

1. Section 1.0 Introduction (p.1): “The dam impounds approximately 22,425 feet of Rocky River and six perennial tributaries”. This sentence is confusing because it can be read that the dam impounds 22,425 feet of Rocky River. We suggest this sentence is changed to reflect that the dam impounds 16,060 linear feet of Rocky River and 6,365 linear feet of perennial tributaries.

This language will be clarified in the Mitigation Plan

2. Section 1.3, Bank Objectives (p.2‐3): Table 1 describes the bank goals and methods of achievement. Six goals are listed for the bank; however, several of these goals are restatements. For example, goals 2, 3, and 6 all refer to restoring natural flow regime, managing sediment, and or/improving habitat.

In comments from the USACE on the Draft Prospectus, they requested that we “reword and restructure [our] bank objectives to match those deemed applicable within the 2008 [Dam Removal] Guidance because those objectives reflect successful targets identified years ago by the resource agencies”. For that reason, the Bank Objectives Section is presented in the format seen in the Final Prospectus.

3. Section 2.2, Assurance of Sufficient Water Rights (p.4): Indicated the hydro facility was bought by the Bank Sponsor. The FERC library does not show any records of transfer of the exemption. Please provide additional information regarding the transfer of the FERC exemption between the previous owner and the Bank Sponsor.

A letter notifying FERC of the change in ownership was submitted by Timothy Sweeny on May 14, 2014. Mr. Sweeny has since received notification that it was accepted by FERC and should now show up in the library.

4. Section 2.3, Proposed Service Area (p.5): The bank Sponsor is requesting the proposed service area for this mitigation bank include Cape Fear HU 03030003, and the urban growth areas of Cape Fear HU 03030004. The Bank Sponsor indicates these two HUs have the same physiographic characteristics and the HU boundary is arbitrary. Generally, we believe the service area should be designated based on the location of the mitigation bank (i.e. Cape Fear HU 03030003), and using credits outside of the service area should be determined on a case‐by‐case basis. However, if additional information is included that documents the physiographic and ecological similarities between the original HU and the urban growth areas of Cape Fear HU 03030004, then it can be considered.

The draft mitigation plan will include a section that describes the similarities between HU 03030003 and the urban growth areas within the piedmont of HU 03030004 in order to supplement our request for the applicability of the mitigation bank to both service areas.

5. Section 2.4.2, Feasibility (p.7): Under Phase III it indicates removal of the remaining portions of the dam. Although it appears to be indicated in previous sections (e.g. Section 1.0), we recommend the entire powerhouse is removed as well as the dam.

The entire powerhouse will be removed with the dam. This will be explained clearly in the demolition plan within the Mitigation Plan.

6. Section 2.4.2, Feasibility (p.7): Under Phase III it indicates removal of the remnant rock dam upstream of Hoosier Dam. The boulders from this dam would be incorporated into habitat enhancement measures on Rocky River. We recommend the boulders are placed to mimic natural stream conditions and appropriate instream habitat rather than randomly placing the boulders in the stream channel.

Care will be taken to place remnant rock material throughout the drained impoundment region in such a way that it mimics naturally occurring rock features on other portions of Rocky River.

7. Section 3.2, Baseline Site Conditions (p.8): A discussion of the baseline site conditions is included for water quality and threatened and endangered species. However, there is no discussion of the existing aquatic community (i.e, benthic macroinvertebrates, fish, and freshwater mussels). Baseline (i.e., pre‐removal) data for the aquatic community should be collected to develop success criteria and document the specific changes that occur in the aquatic community following dam removal. The pre‐removal (baseline) and post‐removal survey designs should be coordinated with the IRT prior to data collection to ensure appropriate data is collected to document success criteria have been met. Pre‐removal and post‐removal data should be collected in Rocky River and any tributaries where mitigation credit is sought. All surveys should be conducted by biologists with both state and federal endangered species permits. Also, exotic aquatic or terrestrial plant or animal species (e.g., flathead catfish) that may be present within the mitigation bank, or that may be introduced to the mitigation bank by removal of the dam should be identified.

An extensive biological monitoring plan including baseline and post‐dam removal has been developed based on previous dam removal projects and input from the US FWS. Wildlands has attached this plan that discusses each of these concerns including monitoring protocol, success criteria, and the handling of endangered species by companies with state and federal endangered species permits. This discussion can be found in Sections 2.1.4, 2.2.2 and 2.2.3.

8. Section 3.2.4, Existing Riparian Buffer Vegetation (p.8‐9): The Bank Sponsor Indicates approximately 35% of the riparian buffer along Rocky River within the bank limits has been purchased or protected. In addition, 100% of the buffer along Tributaries 3 and 4, and approximately 33% of the buffer along Trubutary 2 has been purchased and protected. Information regarded how these riparian buffers are protected (e.g. permanent conservation easement) should be included.

Please refer to the response to the NCDENR comment #2. The land has been purchased by the Bank Sponsor. If mitigation credits are awarded for the establishment of conservation easements, then the Bank Sponsor will place conservation easements along the Rocky River according to the percentages described above. Conservation easements will be recorded on both sides of any tributaries for which credit is requested. Final copies of these easements will be provided in the final mitigation plan.

9. Section 3.2.5, Water Quality (p.9): Baseline water quality data was collected in the summer of 2013 within the reservoir, upstream of the reservoir, and downstream of the dam. It is likely additional water quality sampling will be needed to establish an adequate baseline. In addition, specific water quality improvements that will be achieved by removal of the dam (i.e., success criteria) should be defined. The pre‐removal (baseline) and post‐ removal survey designs should be coordinated with the IRT prior to data collection to ensure appropriate data is collected to document success criteria have been met. Also, in addition to collecting water quality data in Rocky River, pre‐ and post‐removal water quality data should be collected in any tributaries where mitigation credit is sought.

The baseline and annual monitoring protocol and success criteria for water quality are discussed in Sections 2.1.2 and 2.2.4 of the attached supplemental monitoring guidelines. They include collecting water quality data along the tributaries where mitigation credit is sought. These protocols will be discussed with the IRT prior to implementation to establish a final agreed upon monitoring plan.

10. Section 3.2.6, Sediment Characterization and Management (p.13): Indicates a bathymetric survey, Tier 1, and possibly Tier 2 analysis of sediment will be performed, and a Sediment Management Plan will be developed. We are concerned about sediment and its impact on downstream aquatic resources. In addition to the Cape Fear shiner, there are several state listed freshwater mussel species downstream. The volume, level of contamination, and potential risks to downstream aquatic resources will determine how the sediment should be managed. However, in the past, sediments were required to be removed (dredged) prior to dam removal in a watershed that supported federally listed species downstream of the project.

On July 16, 2014 Wildlands met with USFWS staff to discuss the sediment wedge upstream of the Hoosier dam and the possible impacts it may have on downstream aquatic wildlife populations including the endangered Cape Fear shiner. It was determined that Wildlands will perform a Tier 1 evaluation, which investigates potential sources of contamination within the contributing drainage area, the physical characteristics of the sediment behind the dam and a bathymetric study to determine the volume of the wedge. This evaluation will then be submitted to the USACE with a determination of whether a Tier 1 evaluation is sufficient or a Tier 2 evaluation should be completed in order to further rule out contamination. The USACE will then provide the document to the USFWS who will do their own evaluation to determine if the dam removal is likely to have a positive or negative effect on fish populations including the cape fear shiner. This evaluation will determine whether sediment will be dredged from behind the dam.

11. Section 3.2.7, FERC License (p.13): It states the Bank Sponsor will surrender the Exemption #3586 to the FERC License in Compliance with the FERC Regulation 4.102. According to the FERC regulations, the exemption holder must consult with the fish and wildlife agencies on the plans for disposition of facilities and site restoration. Also, the exemption holder must fulfill any obligations imposed by FERC and the fish and wildlife agencies for disposition of facilities and site restoration. It is our understanding the application to be filed with FERC is essentially the same as a relicensing application, and includes an environmental assessment of the dam removal and restoration.

Yes, the above process description is the one that will be followed by the Bank Sponsor.

12. Section 4.0, Mitigation Work Plan (p.15): Under Dam Demolition and Dewatering Work Plan it indicates the initial dewatering of Reeves Lake would occur in a manner that minimizes water quality and ecological impacts to downstream water bodies and aquatic communities while maintaining instream flows. Also, in Section 2.4.2, Feasibility (p.6), under Phase I it indicates reservoir draining would occur in late fall through early winter through the existing powerhouse.

Detailed information regarding the proposed dewatering of Reeves Lake should be included. We support dewatering the impoundment during late fall through early winter. Dewatering should occur in a slow controlled manner that will not result in the scouring or erosion of downstream habitat, and will not result in the downstream flushing of sediment from within the reservoir. In addition, details describing how the impoundment will be drawn down, the proposed drawdown schedule that includes the release flow (CFS) for the impounded waters, and how minimum flows downstream of the dam will be maintained during the entire dam removal process to minimize impacts to aquatic resources should be included.

Also, we request the Bank Sponsor notify NCWRC regarding the date and time of dewatering of Reeves Lake is initiated. We would like the opportunity to relocate any freshwater mussels that may be stranded during the dewatering.

There will be a section of the Mitigation Plan dedicated to demolition and dewatering that will explain the process in detail. Per your request, NCWRC will be notified regarding the date and time of dewatering of Reeves Lake providing enough time for relocation procedures.

13. Section 4.0, Mitigation Work Plan (p.15): Under Wooded Buffer Restoration Plans it indicates planting lists and details will be included. We recommend re‐vegetation of riparian buffers with native trees and shrubs. A reference site located within, near, or adjacent to the bank should be used to develop the plant list for re‐ vegetating riparian buffers within the bank. In addition, if it is determined these riparian buffers will be used for mitigation credit, then success criteria will need to be developed.

Wildlands will follow the methods used in their previous riparian buffer restoration projects for the design and establishment of riparian buffers along Rocky River and its tributaries. It should be noted that the majority of the riparian buffer along Reeves Lake and its tributaries is currently vegetated with mature bottomland hardwood species. Adjacent native vegetative communities will be used as a guideline for the plant list along with species with high survivability noted on previous riparian buffer restoration projects. The mitigation plan will outline the success criteria for these buffers.

14. Section 4.0, Mitigation Work Plan (p. 15): Under Monitoring Plan it indicates pre‐ and post‐ removal monitoring will include geomorphic surveys. If the success criteria for the tributaries will include channel stability, then stream geomorphology data should be collected immediately after the reservoir is drawn down for use as pre‐removal (baseline) data.

Wildlands will follow the above procedure as part of the baseline data collection. This is described in Section 2.2.1 of the attached supplemental monitoring plan.

15. Section 5.0 Determination of Mitigation Credit (p.15): It states “The upstream limits of the impounding effect of the Hoosier Dam on Rocky River and six perennial tributaries were initially estimated based on the water level of Reeves Lake and LIDAR data for the tributaries. The upper limits of these inundated areas were visited, photographed, and field verified using hand‐held global positioning system equipment... The final lengths for the Rocky River and each of the six tributaries will be confirmed by topographic survey of the limits of the impounded area."

In the past, determining impoundment limits has been problematic particularly on short tributaries. Detailed information describing how the impoundment limits were determined should be included.

This will be included in the Mitigation plan.

16. Section 5.0, Determination of Mitigation Credit (p.16): Table 3 shows mitigation criteria for improving water quality, rare, endangered, and threatened species, and protecting wooded buffers. The table does not show “establishing an appropriate aquatic community” as part of the mitigation criteria. Establishing an appropriate aquatic community is listed as a goal in Table 1, and is an important component in determining the success of a dam removal project. Also, the aquatic community was not discussed under baseline site conditions. Please provide additional information regarding how “establishing an appropriate aquatic community” will be determined and how it fits the mitigation criteria.

This criteria will be evaluated with biological surveys conducted pre‐ and post‐ dam removal to determine if the species composition has shifted in representation from lentic to lotic. The protocol for aquatic community sampling is discussed in Sections 2.1.4, 2.2.2 and 2.2.3 of the attached supplemental monitoring plan.

17. Section 5.0, Determination of Mitigation Credit (p.16): Table 3 shows credit for Rare, Endangered, and Threatened Species for the Rocky River and each of the six tributaries. We question whether all of these tributaries will provide suitable habitat for rare, threatened, or endangered species. Generally, restoration of the tributaries following dam removal is not as effective as restoration of the main channel where the dam was located. If credit is sought for each of the tributaries, then pre‐removal and post‐removal data will need to be collected in each of the tributaries to document success criteria were met in each tributary.

Collection of data in the tributaries is discussed in the attached supplemental monitoring plan. We will not claim credit if success criteria are not met within the tributaries.

18. Section 5.0, Determination of Mitigation Credit (p. 16): It states "Based on initial comments from the IRT, generation of stream mitigation credits for water quality improvements and restoration of rare, threatened, and endangered species for the Rocky River and the six perennial tributaries will not exceed a ratio of 1:1. The Bank Sponsor proposes to preserve riparian buffers along a significant portion of the mainstem of Rocky River and its tributaries. This approach to preserving buffers along the mainstem has not been undertaken on any previously approved dam removal mitigation projects. For this reason, we propose to generate credit above the base 1:1 ratio following the methodology in the rescinded dam removal guidance."

This was a possibility in the rescinded dam removal guidance (i.e., Determining Appropriate Compensatory Mitigation Credit for Dam Removal Projects in North Carolina, June I9, 2008). However, it was anticipated the buffer credits generated would compensate for tributaries that most likely would not meet all three success criteria (i.e., water quality, aquatic community, rare, threatened and endangered species) and therefore would not qualify for the 1:1 ratio. Tributaries are more easily impacted and wooded buffers provide additional protection to the tributaries. We question whether mitigation credit should be given for any of the tributaries unless they have protected wooded buffers. Review of previous dam removal mitigation banks has shown tributaries without protected wooded buffers often have significant degradation of aquatic habitat. We believe further discussion with the IRT is needed regarding mitigation credit for tributaries and/or wooded buffers. Also, there appears to be some discrepancy between the percentages of buffer protected on each of the tributaries as described in Section 3.2.4 (p. 8‐9) and Table 3 (p. I6).

The Bank Sponsor is not claiming credit on any tributaries without a proposed riparian buffer and easement. Any discrepancies between Section 3.2.4 and Table 3 will be reconciled in the draft mitigation plan. As mentioned in the response to NCDENR question #2 and NCWRC question #8, conservation easements will be recorded on the Rocky River if the Bank Sponsor is compensated with mitigation credit.

Comments from Pete Benjamin, USFWS April 10, 2014

1. During the draft prospectus review meeting, Emily Jernigan expressed the Service's concerns with removing the sizeable dam in such a sensitive area for the Cape Fear shiner and numerous other Federally At Risk and State rare species. The concerns primarily stem from the lack of available scientific data in regards to the exact quantity and quality of sediments and nutrients the dam is holding back (NPDES discharges, runoff, etc.); and how the release of the impounded water and sediments could potentially negatively affect the downstream ecosystem as a whole. Specific concerns are for the potential impacts to the Cape Fear shiner and its designated downstream Critical Habitat associated with the dam removal. In addition to the Cape Fear shiner, there are several Federal At Risk species that live downstream of the Hoosier Dam including: Atlantic pigtoe (Fusconaia masoni); brook floater (Alasmidonta varicosa); and the Septima's club tail (Gomphus septima). North Carolina rare species found downstream of the dam include: the panhandle pebblesnail (Somatogyrus virginicus); notched rainbow (Villosa constricta); triangle floater (Alasmidonta undulata); Carolina creekshell (Villosa vaughaniana); eastern creekshell (Villosa delumbis); and the creeper (Strophitus undulatus). As discussed during our May 13, 2013 meeting, the Service recommends the Corps request to begin the consultation process, as the proposed activities may affect the Cape Fear shiner, and may adversely modify the designated Critical Habitat downstream of the dam location depending on the actions taken. This process will be the most appropriate avenue to adequately address all of the potential concerns in addition to the desired species benefits associated with this proposed project.

Wildlands and the Bank Sponsor have begun the consultation process with Emily Jernigan as requested. The first meeting took place July 16, 2014 to discuss the Tier 1 evaluation for sediment behind the dam as well as potential impact the sediment and dam removal itself may have on aquatic life including the Cape Fear shiner. Wildlands and the Bank Sponsor will continue the consultation process throughout the project to ensure all concerns regarding aquatic life are addressed.

2. The Service is pleased to know the prospectus states that a sediment management plan will be established in the Mitigation Plan, and will be developed such that the risk of short‐term impacts to sensitive aquatic communities downstream is minimized, and long‐term impacts are avoided altogether. A sediment management plan should be based on site‐specific assessment of sediment quantity and quality. It should discuss how sediment is to be managed before and during the removal and include the anticipated impacts of sediment movement post‐removal (on upstream and downstream sediment loading, bank stability, and sediment and water quality), particularly as related to Cape Fear shiner habitat. Any proposed mitigative measures and monitoring should also be included.

Wildlands will follow the suggestions above in developing the sediment management plan to be included in the draft mitigation plan.

3. The Service applauds the Bank Sponsor's initial efforts to acquire the majority of the Rocky River mainstem and associated tributary buffers, and encourages these efforts to continue to incorporate additional buffers along the entire project reach; as it will benefit the Cape Fear shiner's habitat and additional aquatic and terrestrial species as a whole. Wildlands Engineering has indicated that more conservation easements are in the process of being acquired along the project reach, and the Service supports these conservation efforts. The Service recommends that in order to receive credit for the approximately 6,365 linear feet of tributaries proposed, the tributaries should be protected with conservation easements which include a buffer on each side of the channel; preferably a 300‐foot forested buffer wherever this is possible. We also encourage the establishment of 300‐foot forested buffers and conservation easements on as much of the Rocky River mainstem as possible. Even with forested buffers and conservation easements, the Service would be concerned about allowing 1:1 credit ratios for tributary reaches that are deeply incised, or observed to be lacking in desired natural aquatic functions. We look forward to viewing the impounded areas, reviewing the total property easement acquisitions, and discussing potential credit ratios.

As mentioned in the response to NCDENR question #2 and NCWRC question #8 and #18, conservation easements will be recorded on the Rocky River if the Bank Sponsor is compensated with mitigation credit. The bank sponsor has not yet decided on the width of buffer to be protected but will take the USFWS comment under advisement. Geomorphic surveys will be conducted on the tributaries and Wildlands will coordinate with the IRT regarding the suitability of these systems for credit generation.

4. In general, the Service does not have concerns with structuring available credits around goals of the project (reestablishment of flow, endangered species habitat improvement, water quality improvement, fish passage, etc.). However, we caution that all goals and success criteria should be quantifiable and reasonable, and the amount of credits offered for reaching the goals should be appropriate for the level of effort and measured level of improvement. We look forward to discussing potential goals, success criteria, and available credits in an effort to retain consistency with other proposed dam removal projects.

Success criteria have been outlined in regards to aquatic communities, water quality, geomorphology and the re‐ colonization of rare, threatened and endangered species in the attached supplemental monitoring document. Success criteria in the monitoring document are quantifiable based on monitoring data and have been modeled after previous dam removal projects. Wildlands intends to discuss this document at the IRT meeting on July 22, 2014 before inclusion of these criteria into the draft mitigation plan.

5. The Service anticipates that the Mitigation Plan will include, at a minimum, proposals for monitoring of fish passage and habitat quality for the Cape Fear shiner and other rare native aquatic species, water quality, sediment quantity, quality, and movement, vegetation recruitment and invasive plants, and shoreline stability. We recommend using appropriate native vegetative species that would benefit the Cape Fear shiner and the Rocky River system, such as American water willow (Justicia americana), when preparing the replanting component of the mitigation plan. In addition, remedial plans should be included, should the provider fail to meet stated goals

The mitigation plan will address the topics listed above including planting of native vegetation, success criteria and long term management plans.

Comments by Renee Gledhill‐Early, SHPO, March 17, 2014

l. There are no recorded archeological sites in the project vicinity, but the document states that a Phase I cultural resources investigation is anticipated to be undertaken. We concur with this recommendation and look forward to review of the document. The investigations should include background research documenting the history of the dam and the power generating facilities, as well as a pedestrian survey of the project area of potential effect (APE). The aerial photograph noted Henley’s Mill. If a mill exists, background research should be conducted and the structure or remains investigated. Potential project effects to this mill should be assessed. We would suggest that the applicant, or their archaeological contractor, meet with staff of the Office of State Archaeology prior to undertaking the Phase I investigation to ensure that all expectation concerning the investigation are anticipated.

Two copies of the resulting cultural resource report, as well as one copy of the appropriate site forms, should be forwarded to us for review and comment as soon as they are available and well in advance of project implementation.

Wildlands and Unique Places will continue to coordinate with SHPO throughout the Phase I cultural resources investigation and provide the requisite copies of the resulting cultural resource report the SHPO office and the IRT.

Comments by Jean Gibby, USACE June 5, 2014

l. In an electronic correspondence dated July 3, 2013 regarding this project, the Corps of Engineers requested that a jurisdictional determination be conducted for this project and included in the prospectus. To date, a jurisdictional determination for this site has not been conducted. You must identify and quantify all jurisdictional waters within the project area and include the source of hydrology for each. As part of your jurisdictional determination, you should complete USACE and North Carolina Division of Water Resources (NCDWR) stream forms, upstream of the impounded areas, in order to describe the anticipated return of functions. You will also need to assess the potential impacts to all wetlands from the proposed dam removal. Any wetland impacts that cannot be avoided may require a separate compensatory mitigation plan. Furthermore, depending upon the amount of loss of wetland resources, and/or adverse impacts to other aquatic resources, and individual DA permit may be required for this project. Please be aware that even if a Mitigation Banking Instrument (MBI) and mitigation plan for this proposed project is approved, the DA individual permit authorization would be issued or denied based upon criteria as determined by our Section 404(b)(1) guidelines and public interest review.

A wetland and stream delineation is currently being conducted for this site and a jurisdictional determination will be requested (estimated completion date August 1, 2014). The corresponding forms mentioned above will be included in the draft mitigation plan. Discussion and analysis of wetland impacts will also be included in the mitigation plan.

2. Additional information regarding impacts of the proposed work on the six (6) tributaries will need to be addressed in the draft mitigation plan. As impact to the tributaries has not yet been addressed, the amount of credit, if any, to be provided by these tributaries will need to be determined after review of the draft plan. As mentioned by the North Carolina Wildlife Resources Commission (NCWRC) in their April 10, 2014 letter, additional information regarding the establishment of the impoundment limits of the tributaries, establishment of appropriate aquatic communities, determination of habitat for threatened and endangered species within the tributaries and the use of wooded buffers will be necessary regarding the final establishment of potential credits (see also number 5 below).

The draft mitigation plan will address impacts and proposed worked on the six tributaries. As you mentioned, some IRT members voiced concerns over the tributaries. Those regarding biological community, water quality, endangered species, and geomorphic stability monitoring and success criteria are addressed in the attached supplemental monitoring document. Wildlands will gather input Tfrom the IR regarding the monitoring document before the completion of our baseline monitoring and include that input into the draft mitigation plan. Also as previously discussed, credit will only be sought for tributaries that include riparian buffers in conservation easements.

3. Please be aware that the credit release schedule and service area have not been determined. These items still need to be resolved and will depend, in part, on much of the information that will be included in the draft mitigation plan and draft mitigation banking instrument.

This is noted, and we will continue to communicate with the IRT throughout this process.

4. Based on comments received from the U.S. Fish and Wildlife Service (USFWS), we have initiated informal consultation regarding the Cape Fear Shiner by letter dated June 5, 2014. Please consider all information provided during this process and incorporate it into your draft mitigation plan and draft MBI.

Wildlands has begun to consult with USFWS and had a meeting regarding the Cape Fear Shiner on July 16, 2014. Discussions in this meeting led to the development of the attached monitoring document. Wildlands will continue to work closely with USFWS throughout the project and will incorporate methods for protecting the Cape Fear shiner pre, during, and post dam removal in the draft mitigation plan.

5. As indicated in your prospectus and the April 15 letter from the NCDWR and the April 10, 2014 letter from NCWRC, additional water quality monitoring , aquatic community data and geomorphic data (both pre and post removal) will be necessary to aid in the development of performance standards and credit determination. This data collection should be coordinated with the IRT as the draft mitigation plan and draft MBI are developed.

Wildlands has provided the attached supplemental monitoring doument in order to get a consensuse from th IRT moving forward on acceptable monitoring protocols and success criteria. The draft mitigation plan will include the monitoring protocol as agreed upon by the IRT.

6. As indicated in your prospectus, a more detailed evaluation of sediment quantity and quality above the Hoosier Dam must be completed and a more detailed sediment management plan must be developed. As indicated by the USFWS and the NCWRC in their April 10, 2014 letters, the plan should discuss how much sediment is to be managed before and during the removal and include the anticipated impacts of sediment movement post‐removal. You should also include any proposed mitigation and monitoring associated with sediment removal.

The subjects mentioned above will be included in the draft mitigation plan. Wildlands is currently performing a bathometric study of the impounded sediment and is starting a Tier 1 evaluation of the impoundment, which, along with consultation from the USFWS, will drive the development of the sediment management plan.

7. Please continue to coordinate with the State Historic Preservation Office regarding potential impacts to cultural resources.

Coordination will continue with the SHPO and information regarding correspondence will be provided to the IRT.

8. Please consider and address the recreational uses of the existing resource by the adjacent property owners/citizens expressed in the attached letters.

The concerns regarding the recreational uses of the existing resources and other comments from adjacent property owners/citizens is being addressed in a separate comment response letter, which will be provided to the USACE at a later date.

Please contact me at 919‐851‐9986 x 102 if you have any questions.

Sincerely,

John Hutton Title

Enclosure: Monitoring Document