Stormwater Best Management Practices Assessment for the City of Lincoln, Nebraska

The objective of this research was to assess BMP performance and implementation in Lincoln, Nebraska. In order to accomplish this objective, four tasks were established: sampling of stormwater runoff at eight sites located upstream of Holmes Lake, inspecting BMPs at construction sites in Lincoln, sampling and analysis of soil phosphorus levels in the Holmes Lake watershed, and conducting discussions with professionals involved with stormwater management in Lincoln. Based on the information collected during these tasks, several recommendations regarding the BMP assessment process are made including: recommendations for sampling site selection, an inexpensive flow monitoring method, and a rapid construction site BMP assessment protocol

In Search of HPA Axis Dysregulation in Child and Adolescent Depression

Dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis in adults with major depressive disorder is among the most consistent and robust biological findings in psychiatry. Given the importance of the adolescent transition to the development and recurrence of depressive phenomena over the lifespan, it is important to have an integrative perspective on research investigating the various components of HPA axis functioning among depressed young people. The present narrative review synthesizes evidence from the following five categories of studies conducted with children and adolescents: (1) those examining the HPA system’s response to the dexamethasone suppression test (DST); (2) those assessing basal HPA axis functioning; (3) those administering corticotropin-releasing hormone (CRH) challenge; (4) those incorporating psychological probes of the HPA axis; and (5) those examining HPA axis functioning in children of depressed mothers. Evidence is generally consistent with models of developmental psychopathology that hypothesize that atypical HPA axis functioning precedes the emergence of clinical levels of depression and that the HPA axis becomes increasingly dysregulated from child to adult manifestations of depression. Multidisciplinary approaches and longitudinal research designs that extend across development are needed to more clearly and usefully elucidate the role of the HPA axis in depression

Feasibility of Integrating Natural and Constructed Wetlands in Roadway Drainage System Design

Stormwater from roadways could have negative effects on the environment and aquatic ecosystems. Typical highway runoff pollutants include solids; heavy metals, particularly cadmium, copper, and zinc; petroleum hydrocarbons; gasoline constituents; PAHs (polyaromatic hydrocarbons); oxygen demanding compounds measured as COD (chemical oxygen demand) and BOD (biochemical oxygen demand); and road salts. Roadway runoff falls under the legislation of the Clean Water Act (CWA) via the National Pollutant Discharge Elimination System (NPDES). CWA regulates discharge of nonpoint source pollutants, such as roadway runoff, by issuing permits to public entities which manage Municipal Separate Storm Sewer Systems (MS4s). Part of the Nebraska Department of Roads (NDOR) permitting requirement is to create a design guide for Best Management Practices (BMPs) tailored to remediate roadway runoff in Nebraska. The objectives of volume I of this research were to characterize the pollutants in roadway runoff and determine the effectiveness of the existing stormwater BMPs at the study site. To accomplish these objectives, eleven rainfall events were sampled from November 2008 through November 2010. First flush and composite highway runoff samples were analyzed for heavy metals, anions, nutrients, particulates, BOD, COD, VOCs, and SVOCs. In addition to the concentrations, event loads were calculated using the hydrologic information from the study site. The results were compared to the Nebraska standards for water quality to establish which contaminants could have a negative impact on the environment. Additionally, an assessment of the effectiveness of the existing detention basin was completed, using the pollutant loads from the different outlet pipes

Development of a Field Test Method for Total Suspended Solids Analysis

Total suspended solids (TSS) are all particles in water that will not pass through a glass fiber filter with a pore size less than 2 μm, including sediments, algae, nutrients, and metals. TSS is an important water quality parameter because of its adverse effects on aquatic species and wildlife. TSS is regulated through the EPA via the NPDES in many states. Since there are no accepted field tests for TSS, projects with TSS regulations must send samples to a laboratory for analysis, which can delay projects for days or weeks. The goal of this research was to develop a rapid, cost-effective, and consistent method for direct measurement of TSS in the field. Theoretical analyses of three initial designs (centrifugation, rapid heating, and rapid filtration using vacuum pressure) showed that in order to obtain sufficient suspended material to measure in the field, too much water would be needed for each sample to be feasible for centrifugation and rapid heating. A new prototype rapid filtration system design was developed for evaluation. Testing showed this system to be inaccurate. A second system was modified for rapid filtration with no vacuum. Testing of this system also showed results were not precise enough to be a feasible field test. It was concluded that none of the described methods were currently feasible, and that the laboratory test could also have inaccuracies in measuring water samples tested to meet regulation standards

Stormwater Best Management Practices Assessment for the City of Lincoln, Nebraska

The objective of this research was to assess BMP performance and implementation in Lincoln, Nebraska. In order to accomplish this objective, four tasks were established: sampling of stormwater runoff at eight sites located upstream of Holmes Lake, inspecting BMPs at construction sites in Lincoln, sampling and analysis of soil phosphorus levels in the Holmes Lake watershed, and conducting discussions with professionals involved with stormwater management in Lincoln. Based on the information collected during these tasks, several recommendations regarding the BMP assessment process are made including: recommendations for sampling site selection, an inexpensive flow monitoring method, and a rapid construction site BMP assessment protocol

Polyurethane foam (PUF) passive samplers for monitoring phenanthrene in stormwater

Pollution from highway stormwater runoff has been an increasing area of concern. Many structural Best Management Practices (BMPs) have been implemented for stormwater treatment and management. One challenge for these BMPs is to sample stormwater and monitor BMP performance. The main objective of this study was to evaluate the feasibility of using polyurethane foam (PUF) passive samplers (PSs) for sampling phenanthrene (PHE) in highway stormwater runoff and BMPs. Tests were conducted using batch reactors, glass-tube columns, and laboratory-scale BMPs (bioretention cells). Results indicate that sorption for PHE by PUF is mainly linearly relative to time, and the high sorption capacity allows the PUF passive sampler to monitor stormwater events for months or years. The PUF passive samplers could be embedded in BMPs for monitoring influent and effluent PHE concentrations. Models developed to link the results of batch and column tests proved to be useful for determining removal or sorption parameters and performance of the PUF-PSs. The predicted removal efficiencies of BMPs were close to the real values obtained from the control columns with errors ranging between -8.46 and 1.52%. This research showed that it is possible to use PUF passive samplers for sampling stormwater and monitoring the performance of stormwater BMPs, which warrants the field-scale feasibility studies in the future