North Carolina Sea Grant

Recent hurricane and tropical storm-induced extreme rainfall events have caused hundreds of culvert washouts across North Carolina. These failures present serious vulnerabilities in the transportation network and pose a safety risk. As part of this study, the North Carolina Department of Transportation provided records for 1410 locations where hydraulic structures were reported to have washed out during Hurricanes Matthew and Florence and during extreme flooding in 2020. These records were analyzed to characterize the pre-storm properties of the structures and to identify factors that indicate high washout risk based on a remote desktop analysis. Drainage area, watershed characteristics, structure capacity, and physical parameters were calculated and compiled for all washouts. The same data were also compiled for nearby structures that did not wash out in a six-county area. Results indicated washouts were most common in small watersheds (0.5 mi 2 [<1.3 km 2 ]), for secondary roads, and for corrugated metal and reinforced concrete culverts with diameters of <72 in. (1.8 m). While the analysis did not reveal any specific parameters or thresholds that definitively predicted a washout would occur, several factors that appear to increase the potential were identified, including absence of a headwall, high headwater over culvert diameter ratios, and lower culvert cross-sectional area to watershed area ratios. We recommend agencies conduct asset inventories and inspections to document existing conditions, identify structures in poor condition or those that are very under-sized, and implement repair and upgrade efforts to help reduce failure risk.

Aquatic monitoring of estuarine and coastal waters remains limited due to steep maintenance requirements for in situ hardware stemming from rapid biofouling and harsh environmental conditions. Monitoring sites will also ideally span a mix of shoreline and open water locations, and the need to travel to remote locations can strain resources and limit the geographic footprint of coastal monitoring programs. To overcome these limitations, we explored opportunities to partner with aquatic industry professionals who work on the water and may be able to incorporate routine site visits for sensor maintenance as part of their day-to-day routines. We specifically focused on collaborating with oyster growers to collect continuous salinity and water level observations on their farms, as part of a community-enabled monitoring program we named “See Salt.” In this short communication, we present the See Salt program as a case study and provide recommendations for others who may be interested in establishing a similar community-supported coastal monitoring program. Our recommendations include the following: (1) establish multi-method evaluation strategies to gain insights on program improvement, (2) invest in hardware that can go long durations without recalibration and cleaning, and (3) provide participants with the equipment and training needed to maintain sensors and validate measurements on their own. While we focus on our experiences monitoring salinity and water levels with oyster growers, the recommendations are not specific or unique to these variables or this partner population; our findings are broadly applicable to aquatic monitoring performed in partnership with non-academic professionals.Supplementary informationThe online version contains supplementary material available at 10.1007/s10661-025-14560-y.

ABSTRACT Onsite wastewater treatment systems (OWTS) are a common wastewater treatment approach in coastal communities. Vertical separation distance (VSD) requirements between the drainfield and groundwater aim to ensure aerated soils for wastewater treatment. When the VSD declines, OWTS can fail. This study evaluated groundwater response to sea level rise (SLR) and the implications for OWTS. A groundwater monitoring network (13 wells) was used to evaluate groundwater depth in Dare County, North Carolina. Groundwater levels were measured with water level meters and pressure transducers. Trends in groundwater depth and SLR were analyzed to evaluate the influence of SLR on groundwater depth. From 1984–2022, mean groundwater levels have risen (∼7.6 mm/year) in response to SLR. Currently, sites at <2.7 m land elevation are most likely to have groundwater depths <1 m and inadequate VSD. Based on current precipitation and NOAA intermediate SLR projections, groundwater depth projections suggest that OWTS at lower elevations are more likely to experience groundwater inundation by 2040–2060. SLR has resulted in reduced VSD causing diminished wastewater treatment capacity in low-lying areas. OWTS VSD requirements are typically static due to regulatory constraints. Future management approaches should consider adapting to rising coastal groundwater levels because of increasing wastewater contamination risks.

Abstract Striped bass,Morone saxatilis, is an anadromous fish native to the North American Atlantic Coast and is well recognized as one of the most important and highly regarded recreational fisheries in the United States. Decades of research have been conducted on striped bass and its hybrid (striped bass × white bassMorone chrysops) and culture methods have been established, particularly for the hybrid striped bass, the fourth largest finfish aquaculture industry in the United States (US $50 million). Domesticated striped bass have been developed since the 1990s and broodstock are available from the government for commercial fry production using novel hormone‐free methods along with traditional hormone‐induced tank and strip spawning. No commercial‐scale intensive larval rearing technologies have been developed at present and current fingerling production is conducted in fertilized freshwater ponds. Larval diets have not been successfully used as first feeds; however, they have been used for weaning from live feeds prior to metamorphosis. Striped bass can be grown out in marine (32 ppt) or freshwater (<5 ppt); however, they require high hardness (200+ ppm) and some salinity (8–10 ppt) to offset handling stress. Juveniles must be 1–10 g/fish prior to stocking into marine water. Commercially available fingerling, growout, and broodstock feeds are available from several vendors. Striped bass may reach 1.36 kg/fish in recirculating aquaculture by 18 months and as much as 2.27 kg/fish by 24 months. Farm gate value of striped bass has not been determined, although seasonally available wild‐harvested striped bass are valued at about US $6.50 to US $10.14 per kg and cultured hybrid striped bass are valued at about US $8.45 to US $9.25 per kg whole; the farm gate value for cultured striped bass may be as much as US $10.00 or more per kg depending on demand and market. The ideal market size is between 1.36 and 2.72 kg/fish, which is considerably larger than the traditional 0.68 to 0.90 kg/fish for the hybrid striped bass market.

In some states, the Stream Quantification Tool (SQT) has been adopted to quantify functional change of stream mitigation efforts. However, the ability of the SQT protocol to predict biological function and uphold the premise of the Stream Functions Pyramid (Pyramid) remains untested. Macroinvertebrate community metrics in 34 headwater streams in Piedmont, North Carolina (NC, USA) were related to NC SQT protocol (version 3.0) factors and other variables relevant to ecological function. Three statistical models, including stepwise, lasso, and ridge regression were used to predict the NC Biotic Index (NCBI) and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness using two datasets: 21 SQT variables and the SQT variables plus 13 additional watershed, hydraulic, geomorphic, and physicochemical variables. Cross-validation revealed that stepwise and ridge outperformed lasso, and that the SQT variables can reasonably predict biology metrics (R2 0.53–0.64). Additional variables improved prediction (R2 0.70–0.88), suggesting that the SQT protocol is lacking metrics important to macroinvertebrates. Results moderately support the Pyramid: highly predictive ridge models included metrics from all levels, while highly predictive stepwise models included metrics from higher levels, and not watershed hydrology. Reach-scale metrics were more important than watershed hydrology, providing encouragement for projects limited by watershed condition.

© 2019 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).CORRESPONDING AUTHOR: R. H. Moss, rhm2137@columbia.edu

ABSTRACT Tourism employers and tourism-dependent communities have come to rely on migrants to fill the considerable labor needs of the tourism industry. However, migrants are not always well integrated into the communities that they support, leaving them, the tourism industry, and tourism-dependent communities vulnerable. Set in a community where migrants have been welcomed and well integrated this study utilized in-depth interviews and focus groups with migrants, residents, tourism business owners, and policymakers to identify strategies that have helped Hispanic migrants integrate into a tourism-dependent community. Analysis of this qualitative data was guided by the social exclusion framework. This analysis revealed how economic, social, political, and cultural dimensions play a role in migrants’ integration into the community. The findings reveal the importance of applying a multidimensional approach to integrating migrants into tourism-dependent communities—e.g. language, an element of the social dimension, facilitated activities related to the political dimension. Based upon these findings multiple strategies for integrating migrants into tourism-dependent communities are presented. These strategies move the literature beyond a descriptive identification of the challenges migrants face in integrating into tourism-dependent communities. Such strategies provide opportunities for tourism-dependent communities to improve the well-being of the tourism industry through the well-being of migrants.

Participatory modeling has tremendous potential to promote individual and group learning in environmental decision-making processes. We have implemented a participatory modeling process, the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS) process, in 14 communities to support municipal planning in the face of climate change. We emphasize learning through the dynamic process of developing the capacity to think critically, creatively, and collaboratively in support of individual and group decision-making and planning to remedy a problem of common concern. Participant feedback emphasizing the importance of learning via development of capacities that support activities of thinking and planning, rather than learning via the transfer of knowledge, prompted us to consider more deeply how we design participatory modeling processes and evaluate learning in them. In this chapter we provide a brief overview of the VCAPS process. Second, we interpret learning in our VCAPS process using a combination of a socio-cultural theory of action and a framework from developmental psychology. Third, we reflect upon how these insights informed the development of the VCAPS process. Fourth, we comment on the lessons learned for the theory and practice of learning in participatory modeling.

Natural stream functions in many areas of North Carolina are threatened by changes in watershed hydrology and land use, often resulting in unstable streams with poor habitat and water quality. Impacts include eroding streambanks, unsafe water supplies, impaired habitat, fish kills, flooding, loss of floodplain function, and reservoir siltation. Causes of stream impairment in urbanizing watersheds include increased stormwater runoff, reduced groundwater recharge, road crossings, and loss of riparian vegetation. Over the past decade, natural resource agencies in North Carolina have adopted a natural channel design approach for restoring and enhancing unstable streams. This approach is based on the use of reference stream morphology and biology information. Permitting agencies evaluating the hydrologic, water quality, and wildlife impacts of stream restoration and mitigation projects require that designers use natural channel design approaches. These requirements have facilitated interest among many government and private organizations in learning what restoration techniques are most appropriate for local watershed conditions. Numerous stream restoration projects have been implemented recently by agencies, consultants, Universities, and citizen groups. The purpose of this paper is to describe several urban stream restoration project case studies and lessons learned in North Carolina.