ABSTRACT. With the global increasing water demand, reclaimed wastewater as a potential source for agriculture irrigation after proper treatments has gained much attention. Ferrate, i.e. Fe(VI), with its multi-functions as coagulant, oxidant and disinfectant, may fit in with such treatment requirements. However, existing studies were mainly focused on the mechanisms and kinetics of ferrate treatments in ideal experimental conditions. So in this study, the combined use of ferric, i.e. Fe(III), with ferrate to treat secondary effluent wastewater in different operation conditions were studied to evaluate the treatment performances of various parameters (turbidity, pH, organic matters, nutrients, bacteria indicator, heavy metals). Results showed that turbidity and bacteria indicator should serve as the key evaluation parameters for treatment performance, and based on these, the optimal operation conditions were suggested as dosage of 3 mg/L, Fe(VI):Fe(III)=1:1, velocity gradient of 22 s-1 (30 rpm) and no initial pH adjustment. At such condition, the treated water quality could meet the corresponding EPA water reuse guidelines for TSS and pH; while increased total Fe dosage (up to 54 mg/L) would be required to meet guidelines for bacteria indicator and heavy metals. Further seed germination study comparing both treated and untreated water also proved that the Fe(VI+III) treated water had better impacts on seed germination and seedling growth, indicating that Fe(VI+III) treatment was an appropriate water reclamation technique. The findings of this study have significant implications for addressing the global challenge of increasing water demand, particularly for agricultural irrigation, in a sustainable and efficient manner.

ABSTRACT. Agricultural engineers and chemists have turned to nanomaterials to improve traditional agriculture practices, including pesticide development. Nanopesticides are thought to be a promising course of action for reducing agricultural impacts on agroecosystems. Nanopesticides are able to effectively target pests with smaller quantities and less frequent applications compared to bulk pesticides. However, little is known regarding fate and transport, specifically their influence on wetland ecosystems. This study was to assess the implications of a nano-Cu fungicide and imidacloprid on downstream wetland habitats by using fifteen mesocosm wetlands, containing local soils and native wetland plants. Mixtures of nitrate, nano-Cu, and imidacloprid were applied to the mesocosms at low, medium, and high concentrations. Water samples were collected to determine nanopesticide transformation and degradation rates as well as measure nutrient removal rates; plant and soil samples were collected before pesticide application and at conclusion to measure plant uptake and sedimentation of nanopesticides and nutrients. Interactions between nitrogen, nano-Cu, and imidacloprid were found to increase nitrate removal rates, decrease phosphate removal rates, and inhibit nitrogen uptake in below-ground biomass. Imidacloprid was observed to photodegrade but was not completely removed from the wetlands by the end of the sampling period at high concentrations. Pre-existing copper concentrations in source water led to inconclusive results on nano-Cu removal, however plant uptake and sedimentation of copper were observed. Findings from this study provide insight on fate of nanopesticides in downstream wetland habitats, and provide guidance for the design of best management practices for managing agroecosystem pesticide loads.

ABSTRACT. The University of Maryland (UMD) student chapter of AEES received a Sustainability Grant to build a large-scale algal turf scrubber (ATS) to control the excess nutrient runoff from a UMD parking garage. The grant was written by undergraduate students in AEES and submitted to UMD’s Sustainability Fund. The project will treat the large stormwater discharge capacity from a 1.45 acre, five story parking garage while promoting sustainability initiatives within the university. The grant application included detailed budget specifications, benefits that the ATS would provide to the university, and the maintenance of the system by the AEES student chapter. The ATS system was designed to be 150 m2, with the ATS growth mitigating an estimated 100.7% of the impervious surface area and removing 15.75 lbs of Nitrogen, 1.57 lbs of Phosphorus, and 1722.5 lbs of sediments from the UMD Parking Garage runoff per year. The system is expected to operate for approximately 250 days of year in the temperate Maryland climate and expected to sequester 137.1 lbs in atmospheric and dissolved carbon to produce the harvestable algae. The harvested algae will be used by students and faculty for research. Previous algae research at UMD included anaerobic digestion, creating algal bricks, and making fertilizers. The ATS system will provide immense opportunity for the students at UMD to better understand nutrient uptake rates of algae, carbon sequestration, and algal growth rates. This work will allow for better estimates of ATS implementation opportunities within the greater Chesapeake Bay.

ABSTRACT. The Chesapeake Bay total maximum daily load (TMDL) established estuary nitrogen (N), phosphorus (P), and sediment load targets of 215, 13.3, and 18,600 million pounds per year, respectively. The Chesapeake Bay Program (CBP) estimates that N loads to the Bay were reduced from 370 million lb/yr in 1985 to approximately 258 million lb/yr in 2021 and that P loads were reduced from 29 million lb/yr in 1985 to approximately 15 million lb/yr in 2021. However, the vast majority of these nutrient reductions have come almost exclusively from upgrading point source wastewater treatment plants and reduced amounts of atmospheric N deposition, with wastewater responsible for 65% of N reductions and 76% of P reductions, and atmospheric sources were responsible for 25% of N reductions. In comparison, nutrient reductions from nonpoint urban and agricultural sources were responsible for only 8% of N and 12% of P reductions, while agricultural and urban nonpoint contribute 78% and 74% total controllable anthropogenic N and P loads to the Chesapeake Bay. This gap between actual and actionable loads is primarily because nonpoint source loads have proven particularly challenging to reduce. This presentation details a 3 yr long study by the USEPA CBP Scientific and Technical Advisory Committee to evaluate progress towards meeting TMDL load requirements. Recognizing that the TMDL goal is unlikely to be met, we suggest policies and actions intended to improve program effectiveness, with particular attention to nonpoint source nutrients.

ABSTRACT. As part of a large study by the NC Policy Collaboratory and funded by the NC General Assembly to analyze water quality and investigate nutrient management strategies for Falls Lake, we evaluated the potential nutrient inputs that could be arriving to the Lake from streambank erosion. Streambank erosion conditions ranging from stable to severely eroding and erosion rates were assessed and monitored throughout the watershed. Soil samples at cross-sections were collected and analyzed for nutrient content and bulk density. NCSU also measured flow, turbidity, total suspended solids (TSS) and total phosphorus (TP) at five subwatersheds to generate TSS and TP loads. Field-based assessments of streambank condition and erosion rates were combined with detailed geospatial mapping and modeling of land use and landforms to develop three models to 1) estimate potential locations where erosion was occurring, 2) the height of the streambank and 3) the rate of streambank erosion at 100 feet increments for all the streams in the Falls Lake watershed. Results of all models were combined with measured soil densities to generate a range of predicted sediment loading for each catchment in the watershed. Soil TN and TP concentrations were also used to generate predictions of nutrients for streambank erosion. Our models and field-based work indicated that there may be larger amounts of sediment being eroded, but greater in-channel losses may be occurring. Most of the catchments with the highest loads are closer to the outlet of the watershed and in higher developed areas.

ABSTRACT. We describe our previous and ongoing work on the floodplain channels along the East Fork White River in Indiana. These channels flood well below bankfull conditions, are relatively stable (not filling in with sediment), and exchange a considerable amount of water with the main river channel across a range of flows. This talk will describe how these channels function and how they may serve as a template for enhancing floodplain restoration to remove nitrate (high exchange, long residence time) in a way to that avoids excessive sediment deposition.

ABSTRACT. Trout Unlimited (TU) is implementing watershed-scale ecosystem restoration in the headwaters of the James, Potomac, and Shenandoah River watersheds in Virginia, targeting streams vital for native Eastern Brook Trout (Salvelinus fontinalis). This presentation will detail the multi-faceted approach, combining upland practices to protect water quality, in-stream practices to enhance habitat, decrease bank erosion, and improve aquatic organism passage to reconnect ecological function to focal watersheds.

Throughout several western VA counties, TU is addressing bank erosion with natural channel design methods and bioengineering techniques. Habitat complexity is being improved by adding large woody material and rock structures, creating pool habitat, and providing cover for brook trout.

Riparian buffers are being established through tree plantings and exclusion fencing to control livestock access and reduce sediment runoff. Collaborations with farmers are promoting sustainable agricultural practices, such as cover cropping and rotational grazing, to minimize nutrient loading and improve soil health. Stream crossings, off-stream waterers, and additional BMPs further protect streams from agricultural impacts.

The key to achieving this watershed approach has been a collaborative effort between TU and multiple local, state, and federal agencies and non-profit partners to find projects with willing landowners, secure agreements and resources, and then fully fund and implement the work.

This presentation will combine technical information with visuals and case studies to showcase the project's approach and results. It will be relevant to ecological engineers, fisheries biologists, land managers, and stakeholders interested in outreach, watershed restoration, and native trout conservation.

ABSTRACT. Floodplain restoration has the potential to provide many ecological and societal benefits including habitat and water quality enhancements, recreational opportunities, and flood mitigation. A multi-disciplinary team of agencies, non-profits, and consultants is working to restore floodplain properties along the upper French Broad River to increase resilience and ecosystem values. The Mouth of Mud Creek project was implemented in 2020 on a 100-acre former farm where three backwater sloughs were created for fish habitat enhancement. Additional work included river berm removal to increase overbank flooding, wetland restoration for water quality and habitat, and native plant establishment. Ongoing monitoring work is documenting the benefits of this project in relation to fish use for spawning, nursery, and high flow refuge. A similar project was completed in 2023 on a 70-acre former golf course where a backwater slough was created and a reach of Little Willow Creek was restored. Several other floodplain properties are slated for restoration in the next decade. Successful floodplain restoration requires a team of biologists, engineers, geologists, and land conservation professionals working together to optimize restoration efforts and resource management, including long-term stewardship and monitoring. Lessons learned from existing projects should be integrated into plans for future projects in this and other watersheds to increase flood resilience and ecosystem functions.

ABSTRACT. Riparian zones are important transitional areas between upland and stream ecosystems that improve water quality, provide ecological habitat and corridors, maintain natural hydrologic processes, and provide other important ecosystem goods and services. Riparian management has grown in prominence as these systems have become important foci of stream restoration efforts, stormwater best management practices, and greenspace corridors. Some regional tools have been developed to assess impacts and benefits of riparian zones, but no nationwide models or modeling frameworks adequately capture the effects of riparian outcomes. Existing tools tend to focus heavily into instream outcomes that follow a stream assessment protocol with the inclusion of minor riparian-oriented outcomes. Practitioners have an immediate screening need for multi-taxa tools that can function at national scale to assess impacts and benefits of riparian management actions. For this purpose, we develop the Riparian Ecological Function Index (REFI), which is a semi-quantitative, rapid assessment technique for the national application of riparian ecosystems. REFI structures a framework around three major outcomes: (1) the riparian zone’s effect on instream outcomes, (2) its role in ecological connectivity, (3) how it functions as unique and important habitat. The model follows a semi-quantitative approach that relies on rapid field assessment protocols with optional, but heavily encouraged, desktop geospatial assessments. The REFI is intended for a variety of riparian ecosystems within the United States.