Education

Research Description

Stormwater management, and low impact development and green infrastructure

Honors and Awards

• William Neal Reynolds Distinguished Professor, 2015
• Blue-Green Innovator of the Year in NC, 2014
• American Society of Agricultural and Biological Engineers Young Extension Award, 2008
• Inducted into the Academy of Outstanding Faculty Engaged in Extension (AOFEE), 2007
• Governor's Award for Water Conservationist of the Year, NC Wildlife Foundation, 2007
• NC State Alumni Outstanding Extension and Outreach Award, 2007
• Outstanding Extension Specialist for NCSU and NCA&T for support of county programs from the NCSU Association of Extension Specialists, 2007

Publications

Next generation swale design for stormwater runoff treatment: A comprehensive approach

Ekka, S. A., Rujner, H., Leonhardt, G., Blecken, G.-T., Viklander, M., & Hunt, W. F. (2021). [Review of , ]. JOURNAL OF ENVIRONMENTAL MANAGEMENT, 279. https://doi.org/10.1016/j.jenvman.2020.111756

Designing Dry Swales for Stormwater Quality Improvement Using the Aberdeen Equation

Hunt, W. F., Fassman-Beck, E. A., Ekka, S. A., Shaneyfelt, K. C., & Deletic, A. (2020), JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT, 6(1). https://doi.org/10.1061/JSWBAY.0000886

Field Assessment of the Hydrologic Mitigation Performance of Three Aging Bioretention Cells

Johnson, J. P., & Hunt, W. F. (2020), JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT, 6(4). https://doi.org/10.1061/JSWBAY.0000925

Hydrologic and water quality performance of two aging and unmaintained dry detention basins receiving highway stormwater runoff

Wissler, A. D., Hunt, W. F., & McLaughlin, R. A. (2020), JOURNAL OF ENVIRONMENTAL MANAGEMENT, 255. https://doi.org/10.1016/j.jenvman.2019.109853

Using Irrigation to Increase Stormwater Mitigation Potential of Rainwater Harvesting Systems

Gee, K. D., Hunt, W. F., Peacock, C. H., Woodward, M. D., & Arellano, C. (2020), JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT, 6(2). https://doi.org/10.1061/JSWBAY.0000913

Water Quality and Hydrologic Performance of Two Dry Detention Basins Receiving Highway Stormwater Runoff in the Piedmont Region of North Carolina

Wissler, A. D., Hunt, W. F., & McLaughlin, R. A. (2020), JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT, 6(2). https://doi.org/10.1061/JSWBAY.0000915

Evaluating the Hydrologic Benefits of a Bioswale in Brunswick County, North Carolina (NC), USA

Purvis, R. A., Winston, R. J., Hunt, W. F., Lipscomb, B., Narayanaswamy, K., McDaniel, A., … Libes, S. (2019), WATER, 11(6). https://doi.org/10.3390/w11061291

Field Monitoring of Downspout Disconnections to Reduce Runoff Volume and Improve Water Quality along the North Carolina Coast

Taguchi, V. J., Carey, E. S., & Hunt, W. F. (2019), JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT, 5(1). https://doi.org/10.1061/JSWBAY.0000872

Retrofitting a grass swale with rock check dams: hydrologic impacts

Winston, R. J., Powell, J. T., & Hunt, W. F. (2019), URBAN WATER JOURNAL, 16(6), 404–411. https://doi.org/10.1080/1573062X.2018.1455881

Evaluating the water quality benefits of a bioswale in Brunswick County, North Carolina (NC), USA

Purvis, R. A., Winston, R. J., Hunt, W. F., Lipscomb, B., Narayanaswamy, K., McDaniel, A., … Libes, S. (2018), Water, 10(2).

View all publications via NC State Libraries

View publications on Google Scholar

Grants

Stormwater & Channel Retrofits for the Upper Portion of Hominy Creek Swamp in Wilson, NC

US Environmental Protection Agency (EPA)(1/27/21 - 6/30/23)

×

Stormwater & Channel Retrofits for the Upper Portion of Hominy Creek Swamp in Wilson, NC

Sponsor: US Environmental Protection Agency (EPA)

Start Date: 1/27/21

End Date: 6/30/23

Abstract

Wilson’s Hominy Creek/ Hominy Swamp is a Nutrient Sensitive Water (NSW) with benthos impairment. NC State University and the City of Wilson are partnering to implement five storm water control measure (SCM) retrofits within the City Limits. The retrofits are varied and demonstrate a variety of improvements that can be made across the watershed going forward. They are: (1) the engineering of a headwaters basin to convert it into a functioning stormwater wetland, (2) the improvement of an eroding headwaters channel by either bank stabilizing or linear wetland channel creation, (3) retrofitting an existing wet pond with floating wetland islands, and (4) and (5) converting 2 alleyways into green alleys. In all, more than 130 watershed acres will be treated. In addition to the construction of these 5 retrofits, NC State and the City of Wilson will partner on multiple education programs. The first is a local wetland plant installation and maintenance workshop that will target local landscapers and City of Wilson maintenance staff. The second is a workshop that will be targeted at stormwater design and regulatory professionals highlighting specific retrofits constructed as part of this 319 grant. While the workshop series will be constructed state-wide, one of the offerings will be in the City of Wilson and will highlight these projects as part of a field tour. The City is able to provide a profound amount of match through two separate efforts. The first is the construction of a major ($1.9M) underground detention stormwater retrofit SCM in downtown and the second is applying $80,000 of a $150,000 EEG grant received for SCM design. Thus, the majority of the money requested in this grant is going towards installation (rather than being shared with a substantial amount of design costs). The City will also perform at least some of the construction for three of the SCMs to be constructed: the headwaters basin and both green alleys. A pair of watershed monitoring stations will be maintained and collected data analyzed by NC State. One monitoring station will focus on downtown Wilson runoff (and its consequent treatment); the second will focus on collective headwaters improvement. The two downtown green alley retrofits will be specifically monitored for hydrologic performance. The wet pond retrofit with floating wetland islands will be monitored for water quality improvement. Benthic macroinvertebrate testing will also be conducted at both watershed monitoring stations.

Close

Bradley Creek Water Quality Improvement

US Environmental Protection Agency (EPA)(2/05/21 - 6/30/23)

×

Bradley Creek Water Quality Improvement

Sponsor: US Environmental Protection Agency (EPA)

Start Date: 2/05/21

End Date: 6/30/23

Abstract

Bradley Creek is a tidal creek whose bacterial impairment threatens Wilmington and Wrightsville Beach resident’s recreational and economic opportunities, and ecological communities. In response, the City of Wilmington has set aggressive goals for volume reduction of runoff within the watershed as a way to control and remediate water quality. In an effort to help the city meet these goals, this project proposes creating one and retrofitting four stormwater management practices with improvements that will reduce water quantity and improve water quality within the watershed. These improvements include: 1. Retrofitting the pond in the Sam’s Club parking lot with a bulwark. The current design of the pond has water coming into the pond very near where it exits. This means that treatment time is limited. Installing a solid barrier between the inlet and outlet will force water to flow through more of the pond and provide more treatment. 2. Expanding and converting the wet pond at University Commons into a constructed stormwater wetland. The wetland will be much shallower and contain many more plants. This conversion will not only remove more pollutants, but it will also return more of the water to the underlying groundwater through infiltration. The space will also host much more biodiversity. 3. Retrofitting a swale, or grassed ditch, with native grass species and small dams to slow and pond the water to increase pollutant removal. 4. Disconnecting 8-10 downspouts in a residential townhome complex. Rather than having the gutter downspouts flow over pavement and parking areas, it will be redirected to flow over grass or other landscaping. This way the water can seep into the ground rather than flow into storm drains. 5. Converting a parking lot roundabout into a rain garden. A rain garden is a landscaped area that collects and temporarily ponds stormwater during rain events. The garden then treats the stormwater by allowing it to soak into the ground and be used by the growing plants. This conversion will not only treat stormwater that would have otherwise gone untreated, but it will also alleviate some minor flooding within the parking lot. Together, these 5 improvements will reduce the amount of runoff entering Bradley Creek and will improve the quality of the water that does trickle into the creek. Finally, City of Wilmington personnel and NCSU faculty will deliver multiple educational efforts, targeting both local citizens and the design community.

Close

Evaluating Maintenance Requirements & Water Quality Benefits of Alternative Vegetated & Non‐Vegetated Linings in Roadside Swales

NC Department of Transportation(1/01/21 - 12/31/22)

×

Evaluating Maintenance Requirements & Water Quality Benefits of Alternative Vegetated & Non‐Vegetated Linings in Roadside Swales

Sponsor: NC Department of Transportation

Start Date: 1/01/21

End Date: 12/31/22

Abstract

Swales are the most widely-used stormwater control measure (SCM) in the transportation environment, including linear rights-of-way, highway interchanges, operations and maintenance facilities, and secondary roadways. They are predominant because they are of low expense and easily fit into typical DOT rights-of-way. Swales are usually constructed with turf grass and other low-lying grasses, and recent research (much of which was conducted in North Carolina) demonstrates modest to moderate effectiveness regarding pollutant reduction. However, there are many circumstances when grass-lined swales are impractical, especially when located under a tree line so that the vegetation is shaded or in areas with steep slopes. This situation is conducive to rock lining in lieu of vegetation. Moreover, native deep-rooted grasses are often adapted to growth in swales, and these grasses have different – and less costly – maintenance needs than conventional low-lying turf grasses that need to be mowed. There is little to no information available on how rock-lined and native-deep rooted grass-lined swales perform with respect to water quality. Additionally, research is needed to assign a manning’s roughness coefficient by deep-rooted grasses to flow. Four existing swales and four existing bioswales located at NC State’s Sediment and Erosion Control Research and Education Facility (SECREF) will be used to evaluate water quality performance of alternatively-lined swales. Four of the swales to be tested are currently conventional grass-lined, with the other two being bioswales. Data from previously-conducted experiments will serve as a basis to compare the performance of alternative swale linings. Two different linings will be retrofitted into the existing swales/bioswales. One will be a rock lining (Class B, as specified by NCDOT); the second, a deep rooted native grass mix. Field tests will be conducted in 2021, after a thorough literature review is conducted in autumn 2020. The research team will reach out to NCDOT Roadside Environmental Unit (REU) staff and also reach out to local contractors to determine the costs and availability of alternative swale linings to help NCDOT determine future swale designs. If alternatively-lined swales prove cheaper to maintain while providing at least comparable water quality treatment, the potential for less expensive, yet still safe, operations is likely. NCSU faculty, staff and students will conduct the following tasks as part of this proposal: (1) Conduct a literature review regarding alternative swale linings, included in this is an assessment of local availability and costs (2) Retrofit eight swales (four conventionally-drained and four bioswales) at SECREF. Characteristics of each of the 8 swales as outlined in Table 1. They include two liner types (rock and deep-rooted grass) and slopes (1% and 4%) (3) Run water quality tests, collect data at SECREF and then analyze and synthesize data (4) For two of the swales planted with deep-rooted grasses (Table 1), a manning’s roughness coefficient will be determined, using known flow rates, swale geometries, and slopes, while calculating flow height. (5) Based upon information gained from (3) and (4) above, NCSU will deliver design guidance to NCDOT personnel to help compare performance and maintenance needs of various swale linings under various conditions. The principal deliverable will be an end-of-project Final Report. Moreover, at least one journal article is expected to be produced as part of this research project. Data will be stored in a DPS workbook and later uploaded into the STORMDATA database. By better understanding and predicting swale performance under various lining and design configurations, NCDOT will be able to more efficiently manage runoff within its unique linear environment.

Close

Installation of a Stormwater Monitoring Station for the Duffyfield Subwatershed

City of New Bern(6/01/20 - 6/30/20)

×

Installation of a Stormwater Monitoring Station for the Duffyfield Subwatershed

Sponsor: City of New Bern

Start Date: 6/01/20

End Date: 6/30/20

Abstract

NC State University’s Stormwater Engineering Group (NCSU SEG), a part of the Biological & Agricultural Engineering Department, will install a monitoring station in the Duffyfield subwatershed of Jack Smith Creek in New Bern, NC. This project will be completed in June 2020.

Close

Designing Stormwater Control Measures for Hominy Creek in the City of Wilson

City of Wilson (5/01/20 - 11/30/21)

×

Designing Stormwater Control Measures for Hominy Creek in the City of Wilson

Sponsor: City of Wilson

Start Date: 5/01/20

End Date: 11/30/21

Abstract

Faculty, staff, and students from NC State University’s Biological and Agricultural Engineering’ Stormwater Engineering Group (hereafter NCSU SEG) will design six different stormwater retrofits for future grant submission for the City of Wilson. These projects will all treat sub-catchments of Hominy Branch. The retrofits to be designed include: (1) a large, multi-acre off-line stormwater wetland, (2 and 3) a pair of green alleys in downtown Wilson, (4) a floating wetland island installation in an existing wet pond, (5) the development of an engineering structure and (6) a channel stabilization and linear wetland creation at the headwaters of Hominy Branch. As part of the SCM design, NCSU SEG will survey most of the projects, acquire permits, and monitor one of the tributaries. They will also assist the City of Wilson with the bidding process and construction supervision (were grants to be awarded).

Close

Optimizing Floating Treatment Wetland Deployment to Improve Water Quality

NC Clean Water Management Trust Fund(2/23/21 - 7/31/23)

×

Optimizing Floating Treatment Wetland Deployment to Improve Water Quality

Sponsor: NC Clean Water Management Trust Fund

Start Date: 2/23/21

End Date: 7/31/23

Abstract

Wet detention ponds, or wet ponds, are one of the most common stormwater control measures installed in North Carolina and humid regions throughout the world. While wet ponds are effective at attenuating peak flow, previous research has shown inconsistent pollutant removal efficiency. As ponds are a popular SCM in North Carolina, the improvement of their pollutant removal efficiencies is essential in North Carolina’s nutrient sensitive watersheds. To address these treatment shortcomings, research has recently focused on retrofits to existing wet ponds to improve nutrient removal. One popular retrofit is the floating treatment wetland (FTW). Previous research has begun to address questions surrounding the use of FTWs as a wet pond retrofit, including attempts to quantify nutrient removal and surface coverage requirements for targeted pollutant removal. This project will deploy FTWs at two nutrient sensitive locations in Wilmington and Raleigh, NC to test the effectiveness of placing FTWs at the outlet of a system through pre- and post-installation water quality monitoring and wetland plant biomass analysis in order to close the knowledge gaps with FTWs to the extent necessary to prepare nutrient removal credit guidance for the NC DEQ SCM Credit Document and lead to the implementation of FTWs throughout NC.

Close

Greenfield Lake 319 Wet Pond Retrofit

US Environmental Protection Agency (EPA)(6/01/20 - 12/31/21)

×

Greenfield Lake 319 Wet Pond Retrofit

Sponsor: US Environmental Protection Agency (EPA)

Start Date: 6/01/20

End Date: 12/31/21

Abstract

As a subcontractor to Cape Fear River Watch, the NCSU Stormwater Engineering Group will design, install, and provide monitoring equipment and oversight for an innovative treatment berm retrofit. While wet ponds are effective at attenuating peak flows, previous research has shown inconsistent pollutant removal efficiency. As ponds are a popular SCM in North Carolina, the improvement of their pollutant removal efficiencies is essential in nutrient sensitive watersheds. To address these treatment shortcomings, research has recently focused on retrofits to existing wet ponds to improve nutrient removal. A reactive treatment berm will be installed on private property by a project partner as directed by NCSU. NCSU will partner with one of the nation’s largest stormwater maintenance companies (Apex Companies) to construct and maintain the retrofit.

Close

Swale Research in Continued Support of NCDOT’s Stormwater Program

NC Department of Transportation(1/01/20 - 5/31/20)

×

Swale Research in Continued Support of NCDOT’s Stormwater Program

Sponsor: NC Department of Transportation

Start Date: 1/01/20

End Date: 5/31/20

Abstract

Swales are the most prevalent stormwater conveyance - and therefore potential treatment device - within NCDOT’s linear right-of-way. To date, swale performance with respect to hydrologic change and pollutant retention has been assumed to be modest; however, initial NCDOT-funded research on hydrologic condition (wetland versus upland) and check dam presence has yielded basic results that lead to some potential design improvements. To date, a comprehensive and systematic research program of post-construction swale performance has yet to be conducted. Because swales are such a common practice, small but defined design improvements could yield substantial improvements in runoff quality and quantity released to receiving waters. The purpose of this proposal is to continue swale research support for the NCDOT Stormwater Program. Plot testing has been conducted at NCSU’s Sediment and Erosion Control Research and Education Facility (SECREF) and continued modifications and maintenance of swales is needed. Multiple swale design parameters continue to be tested in this controlled setting, including channel slope, vegetation height (or type), end-of-swale treatment and hydraulic loading ratio. Furthermore, additional swale research is planned utilizing the constructed swales at SECREF. This proposal will continue research and support of further swale design, as well as swale modification, maintenance and repair in support of the NCDOT Stormwater Program.

Close

Piggly Wiggly Subwatershed SCMs

US Environmental Protection Agency (EPA)(1/01/20 - 12/31/22)

×

Piggly Wiggly Subwatershed SCMs

Sponsor: US Environmental Protection Agency (EPA)

Start Date: 1/01/20

End Date: 12/31/22

Abstract

North Carolina State University (NCSU), Biocenosis, and the Piedmont Conservation Council (PCC) are partnering to construct stormwater control measures (SCMs) throughout the impaired Loves Creek watershed to improve water quality and reduce localized flooding. Additionally, educational workshops will be held to encourage the implementation of residential SCMs.

Close

Town of Cary SCM Maintenance Training

Southeast Sustainability Directors Network (SSDN)(1/01/20 - 12/31/21)

×

Town of Cary SCM Maintenance Training

Sponsor: Southeast Sustainability Directors Network (SSDN)

Start Date: 1/01/20

End Date: 12/31/21

Abstract

North Carolina State University Biological and Agricultural Engineering (NCSU BAE) will develop a stormwater control measure (SCM) maintenance training program for the Town of Cary using funds from the Southeast Sustainability Directors Network (SSDN) foundation. NCSU BAE will develop program materials (e.g. lectures, demonstrations, hands-on activities) as well as coordinate and teach four workshops in 2020. Members from the NC Cooperative Extension will assist with the program development and workshops.

Close