impact development (LID) approach that holistically
account for and balance the water quality and quantity impacts of
water technologies in a community.
Congress recently approved a National Decentralized Wastewater Demonstration Project in northeastern North Carolina. The project is called the Pasquotank River Watershed Integrated Water Design Project and is one of six projects funded by Congress. This project will be jointly led by the Albemarle Regional Health Services Agency and the College of Agriculture and Life Sciences at North Carolina State University and will include other partners.
Integrated Water
Designs (IWD) will be developed. These are primarily land-based
technologies that coordinate and combine water management approaches
for small communities in a comprehensive way. Integrated water
designs are a low impact development (LID) approach that holistically
account for and balance the water quality and quantity impacts of
water technologies in a community.
These can include technology designs for on-site wastewater treatment (septic systems), stormwater treatment and removal, drainage, water table management, water supply and agriculture water needs as a part of the project. For this project the IWD will be installed in a demonstration community or subdivision following establishment of baseline water quality conditions. Then the water quality effects of the IWD that are installed in the community will be assessed.
The Pasquotank River watershed is a mixed rural and urban watershed in northeastern North Carolina that covers over 2,000 square miles. There are two distinctively different soil environments in the watershed:
wet, slowly permeable soils on very broad wide flat areas of the mainland that drain to the Albemarle Sound and
sandy, rapidly permeable soils on more sloping land within the barrier islands that constitute the Outer Banks of North Carolina.
Many rural and urban areas in the watershed are growing so rapidly that they present technological challenges for maintenance of water quality and protection of the environment.
Decentralized wastewater treatment systems are utilized throughout much of the rural and developing areas in the mainland portions of the watershed that drain to the Albemarle Sound. The inland portions of the watershed on the mainland include extensive, broad uplands that are quite flat with little elevation change for miles and that have ground water close to the ground surface. Soils oftentimes have clayey or silty subsoils that limit downward movement of water and preclude the use of traditional septic systems, but frequently are underlain by sandy, more permeable soil layers that can allow water movement. Due to these soil conditions, wastewater treatment for homes and businesses is often accomplished throughout the mainland area using a unique decentralized technology that includes a sand lined trench on-site system drainfield on each individual building lot. These are used in conjunction with drainage ditches and/or buried draintubing along the lot perimeters. The purpose of the drainage system is to lower the groundwater table and facilitate wastewater treatment in the underlying soil within these communities. This local drainage is typically connected to subdivision-wide drainage systems either by gravity or pumped drainage systems. The subdivision-wide drainage networks then connect to larger more regional drainage networks throughout the region. All of these must be carefully maintained to function effectively. The regional drainage networks also serve dual purposes for stormwater removal and flood control. Oftentimes, the drainage networks serve agricultural drainage needs to enhance productivity and water quality.
Decentralized technologies are also extensively used for wastewater treatment on the more densely developed barrier islands that occur along North Carolinas Outer Banks.
The Outer Banks extend from communities like Duck and Corolla in the north through the towns of Kitty Hawk and Nags Head down to Cape Hatteras and the town of Buxton in the south. These areas have very sandy soils, often with high densities of development that utilize decentralized wastewater treatment systems. In fact, one of the watershed sub-basins, in a part of the Pasquotank River watershed along the Outer Banks, has the greatest density of septic systems within the entire state and possibly within the country.
The two distinct areas (the flatter mainland and sloping Outer Banks islands) in the Pasquotank River Basin each have unique needs for coordination and integration of decentralized water resources to facilitate residential and commercial development in an environmentally sound manner. Integrated water designs of decentralized technologies for wastewater treatment, stormwater treatment and flood control are needed.
This project will develop integrated water design concepts that minimize and balance potential water resource impacts within a low impact development framework. The original project description planned to develop and test these designs in both mainland and barrier island environments. However, since the funding approved by Congress was less than initially planned, this project will focus on one of these areas, the mainland environment. Therefore, the project will construct and install integrated water designs within a selected demonstration community or subdivision located in the mainland portion of the Pasquotank River watershed.
These integrated designs must be developed to coordinate the sometimes conflicting water management needs for (1) decentralized wastewater treatment systems, (2) stormwater treatment and removal, (3) flood control, (4) sediment and erosion control and (5) water table management to enhance agricultural production. Hence, integrated water designs must account for the effects of water management on a broad range of non-point sources of environmental degradation and pollution.
Communities will be selected and the project implemented by a team led by Mr. Ralph Hollowell and Dr. Mike Hoover. Mr. Hollowell is an Assistant Director and Soil Scientist in the Albemarle Regional Health Services Agency. Dr. Hoover is Professor of Soil Science at North Carolina State University and an Extension Soils Specialist with North Carolina Cooperative Extension. The NC State University project team is expected to include faculty from a number of departments within the College of Agriculture and Life Sciences, including the North Carolina Cooperative Extension as well as faculty from other related colleges in the University.
The Albemarle Regional Health Agency is uniquely qualified to lead this project due to its extensive, unique and forward-looking wastewater management program that extends throughout the entire northeastern corner of North Carolina, covering 11 of the state's 100 counties. This management program currently manages nearly 4000 of the alternative sand lined trench systems and has the capability to integrate its management approach to include the other aspects of water management such as stormwater and flood control, particularly as it relates to integrated designs for environmental protection and water quality management.
A North Carolina State University team led by Dr. Hoover will provide technical assistance to the Albemarle Agency, develop integrated water design concepts for both the mainland and island environments, assess impacts in the demonstration community and provide training and education regarding decentralized technologies and their use during the project.
The NC State University Soil and Water Environmental Technology Center (SWETC) has led the development across the country of hands-on training in these water resource protection areas via its research and training programs centered at the College of Agriculture and Life Science's Lake Wheeler Road Field Laboratory in Raleigh, NC. Some of the major areas addressed by the SWETC include:
On-site Wastewater Management,
Sediment and Erosion Control,
Urban Stormwater Management,
Land Application and Crop Management,
Watershed Management and
Water Table Management
The On-Site Wastewater Management hands-on training center concept was developed by Dr. Hoover nearly 15 years ago and has now been adopted at over 20 other training facilities at universities and colleges throughout the U.S and Canada. Within the past six years that hands-on training center concept has been expanded at NC State University to the broader range of land-based technologies described above for the SWETC Center. Training centers at other universities have not yet incorporated these other land-based technologies, beyond the decentralized wastewater systems, in their hands-on training programs. As a result, the NC State University team has a strong core of faculty and a fairly unique capability to integrate all water management needs into integrated water designs. One critical part of doing this includes enhancement of SWETC Center hands-on demonstrations and training programs to include these IWD concepts.
Following community
selection, the project will characterize existing baseline water
quality conditions prior to design and construction of integrated
water management designs. This will include assessment and source
tracking of key water quality pollutants. Then, integrated water
design concepts will be developed by NC State University for
installation under the direction and coordination of the Albemarle
Regional Health Agency. In addition, decentralized wastewater
technologies (beyond the sand-lined trench system currently used for
wastewater treatment) will be assessed for their potential
incorporation into integrated water designs for both individual
homesites and clusters within communities. The Albemarle Agency's
management entity and management monitoring programs will provide
long-term observation and maintenance of critical water structures
and non-structural components of the integrated water designs during
the project. The NC State University team will assess water quality
improvements resulting from implementation of the integrated designs.
They will compare conditions to baseline conditions prior to use of
integrated water designs and determine the efficacy and usability of
integrated designs. The NC State University team, working in
partnership with the local Albemarle Agency staff will coordinate
technology transfer initiatives for field practitioners via its
training center programs and hands-on demonstrations. The North
Carolina Cooperative Extension will lead public educational
programming efforts for community decision makers and field
practitioners.
This project will take 4 to 5 years to complete due to the need to establish baseline water quality conditions in the demonstration community, develop and install the integrated designs, assess their effectiveness and then provide appropriate training and education programs to disseminate the results.
At this point in time there are six project objectives proposed for consideration in the project workplan. These will be revised and refined in the coming months in collaboration with the US EPA as the workplan is developed. Depending upon other required project activities, such as for federal NEPA requirements and QAPP development (and their costs), some objectives proposed below could possibly have to be substantially modified as the workplan is developed.
Technology development and impacts
Assess on-going impacts of implementation of advanced on-site technologies on land use and development in the Pasquotank River watershed and identify technology-induced trends that are expected to have future impacts.
Develop the Integrated Water Design (IWD) concepts, identify appropriate technologies that fit the design concepts and determine how these technologies are likely to interact together and affect water quality and quantity in a community when considered holistically.
Select a community to demonstrate integrated designs
Select one community or subdivision as a the demonstration community based upon potential for integrated designs to positively influence water quality and community acceptance to participate in the project.
Determine the extent of failing on-site wastewater systems (septic systems) and dysfunctional water management (drainage, flood control, water table management).
Conduct a site survey assessment of each lot in the community to assess on-site wastewater suitability and drainage capability.
Select additional satellite study locations if resources become available from other related projects.
Characterize existing baseline water quality conditions
Establish baseline surface water and ground water monitoring networks in the demonstration community.
Evaluate whether to use bacterial source tracking (BST) and other tracking methods (such as caffeine, pharmaceuticals, etc) in addition to traditional plume tracking approaches to assess potential public health impacts on the community.
Define water quality improvement needs for the demonstration community.
Refine and modify a GIS-based tool (AVSWAT 2000 model proposed) using baseline, monitoring data so as to be able to predict water quality conditions (and ultimately potential impacts of IWD) within other parts of the Pasquotank River watershed.
Extrapolate the method to other satellite sites if resources from other projects are available.
Technology transfer, outreach and education
Develop hands-on demonstrations and deliver practitioner training programs for IWD including on-site wastewater technology, storm water management technology, drainage and water table control in NC.
Deliver educational outreach to community decision-makers in the Pasquotank River watershed.
Educate homeowners in the demonstration community and the watershed.
Install the IWD technologies
Install IWD technologies within one portion of the demonstration community and consider holding a nearby portion of the community constant as a control.
Possibly install IWD technologies to a limited extent at satellite locations.
Evaluate effects of IWD technologies on water quality
Assess impacts of construction of the IWD technologies via monitoring of system performance, surface water, and ground water impacts.
Determine whether the GIS-based tool accounts correctly for the (expected) improvements in water quality.
Co-Project Directors - Hollowell and Hoover
Proposed Project Steering Committee - Albemarle Agency Executive Board of Health
Mac Nixon (Perquimans County)
Harry Lee Winslow (Chowan County)
Sam Shaw (Camden County)
Gene Gregory (Currituck County)
Marshall Stevenson (Pasquotank County)
L.C. Hoggoud (Bertie County)
Proposed Technical Advisory Team
TBD - NCSU faculty, Albemarle Agency staff, DENR staff
Proposed Education Advisory Team
TBD - NCSU SWETC Center faculty, NC Cooperative Extension field faculty and NCRCAP (North Carolina Rural community Assistance Project) staff
Hoover and
Hollowell, April 2004