NCDMF Comments - Town of Kitty Hawk Beach Nourishment

MEMORANDUM: TO: Heather Coats, NCDCM Beach & Inlet Management Project Coordinator FROM: James Harrison, NCDMF Fisheries Resource Specialist SUBJECT: Town of Kitty Hawk Beach Nourishment, Dare County DATE: 16 July 2021 A North Carolina Division of Marine Fisheries (DMF) Fisheries Resource Specialist has reviewed the CAMA Major Permit application for proposed actions that may impact fish and fish habitats. The proposed work is located along 3.9 miles of shoreline, which includes two potential 1000’ tapers, extending from 8 Sea Bass Circle in Southern Shores south to E. Helga Street in Kill Devil Hills in cast the adjacent towns do not construct their projects at the same time. It is expected that this proposal would occur concurrently with the other three Dare County beach nourishment projects. These proposals include the request to conduct dredging and nourishment operations year-round without environmental window restrictions. The beach berm would be filled to an elevation of +6’ NAVD 88 with a 15:1 slope out to tie into the existing grade from approximately -5’ to -11’ NAVD 88. The berm would be constructed at a variable width, ranging from 32’ to 144’ in width. The applicant is proposing to increase the template of the previously constructed engineered dune with this project, increasing the construction elevation from +14’ NAVD 88 to +18’ NAVD 88 with a 25’ design crest width and 4:1 slope down to the +6’ berm elevation (previously permitted at a 3:1 slope). As proposed, a grows excavated volume of up to 1,521,645 cubic yards (CY) of sand is calculated as the volume needed to construct the template along with the advance fill designed to achieve another 5-year design life, given current conditions. The applicant has also included an accounting for losses during the dredge and for future storm erosion, bringing the total quantity of material needed to 2,282,468 CY. It is currently estimated that 118.86 acres (5,5177,541.6 square feet) would be filled below mean high water (MHW) and approximately 70.37 acres (3,062,268 square feet) of material would be placed above the MHW line. Dredging would be constructed via a cutterhead dredge, a hopper dredge, or a combination of the two methodologies. Construction is proposed year-round due to weather-related constraints and in order to minimize time necessary to complete all four beach

nourishment projects in Dare County. The narrative states that based on production rates from the previous nourishment project, it is anticipated to require 2.5 months to complete independently. Should all four projects be completed concurrently, it is expected that all four would be completed within 5 months. A limited amount of sand fencing is also proposed. The narrative states that sand fencing would only be installed along areas of the dune where there has been erosion requiring repairs, and will generally be installed in accordance with the conditions of the exemption for sand fencing found at 15A NCAC 07K. 0212. Should the Town opt to install sand fencing in excess of the requirements of the exemption (in accordance with 15A 07H .0311(c)), the Town will apply for a separate permit modification to allow additional review and will agree to conduct such work after October 31. DMF has concerns with allowing the work to be completed year-round, especially taking into consideration the cumulative area of disturbance for all four towns in one season. Dredge and fill operations year-round, particularly during the warmer spring and summer months, could negatively affect the species present in these areas. Potential impacts include direct mortality through burial or entrance into dredge machinery, excessive sediment particles in the water column which can clog gills, or areal avoidance due to noise and/or turbidity associated with dredge and fill operations. In order to protect the ecologically, recreationally, and economically important finfish and shellfish species, along with the organisms on which they feed and the habitats they utilize, DMF typically recommends a moratorium of April 1 through September 30 for dredge and fill operations. This moratorium protects aquatic resources during periods shown to have high benthic activity, as well as the time in which many species grow to maturity. Furthermore, it is the time of year when finfish frequently utilize shallow waters for refuge and/or forage. Observation of the dredging operations moratorium would help to minimize the potential impacts to aquatic species in the area. However, since the proposed project would be a continuation of projects taking place in neighboring towns, DMF is amenable to allowing this one-time nourishment request to occur without a mandatory moratorium requirement. DMF would recommend, though, that monitoring be included to determine the effects this work will have on important nearshore fish and benthic species and habitats. Additionally, DMF would recommend that the applicant make every effort possible to conduct operations during the above environmental window in order to minimize impacts, rather than plan on conducting operations during the window. The monitoring should include, at a minimum: 1. Pre- and post-placement surveys of benthic species (biodiversity and abundance) in order to determine the impact of dredging and placement on benthic species. 2. Turbidity plume monitoring, to ensure increases in turbidity are not causing significant impacts on the surrounding environment. Ideally, this would include monitoring to observe how widespread the turbidity plume occurs during dredging and placement operations. This should also involve taking water quality samples before, during, and after dredging and disposal operations. At a minimum, this

should be completed once per day, taking measurements before dredging and placement at the dredging location and disposal site, and at least once during dredging and once during placement. Specific parameters should include (at a minimum) turbidity (i.e. secchi depth) and surface and bottom measurements of dissolved oxygen, temperature, and salinity. 3. Habitat surveys at the disposal locations to ensure the projects are not causing significant alterations in habitat type (i.e. SAV, wetlands, intertidal). In cases such as the intertidal area, this would be to show that the placement of material isn't causing a significant shift in habitat types that are based on water depths (removal of shallow habitat and/or conversion of shallow habitat to deeper habitat, conversion of intertidal to subtidal, etc.). 4. Monitoring for dead fish and crabs along placement - any deceased fish/crabs observed in disposal areas (those in which the cause of death isn't obviously related to recreational fishing) should be recorded and reported. This should also include monitoring, recording, and reporting any fish/crabs that are caught and/or killed by dredging equipment. Recordings should include, at a minimum, date/time/location observed, species, and length (tail length - measured in centimeters from tip of the mouth to the tail fork; for crabs, measurement should be the width of the carapace). Pictures are also helpful with this to ensure correct identification and for verification that mortality is related to dredging. If possible, noise monitoring should be included. Ideally, this would occur at varying distances from the dredge and disposal locations. Monitoring should include recording noise levels before or after operations (to provide a baseline) and during the dredging and disposal (to observe the increases that result from the dredging and disposal). Thank you for consideration of our comments. Please contact Jimmy Harrison at [phone] (office) or [phone] (mobile – preferred), or at [e-mail] with any further questions or concerns.