Deicing salts are a major contributor to freshwater salinization in the Northeastern United States, disrupting ecosystem function, aquatic life, and infrastructure integrity. It is often presumed that surface runoff is the dominant mode of chloride transport from impervious surfaces to surface waters despite empirical evidence for soil and groundwater transport. Our project aimed to (1) estimate the hydrologic pathways for chloride transport in a small, urbanized catchment in the Northeastern United States; and (2) provide a critical evaluation of simulation routines commonly used to guide the management of deicing salts. We investigated possible variations in urban chloride pathways by monitoring stormwater discharge and chloride across a winter season with deicing salt spreading and snow accumulation and melt. We analyzed these time series with US EPA SWMM, which presumes chloride transport occurs exclusively via surface runoff into stormwater systems. We develop two parallel models: one using the base empirical temperature-index snow routines, and a second substituting a process-based snowmelt model. Each model was calibrated via the generalized likelihood uncertainty estimation algorithm to both stormwater volumes and chloride mass. Both models adequately simulated water volumes but failed to reproduce observed chloride dynamics, suggesting substantial deicing salt movement through soils and groundwater as a major urban hydrologic pathway. The results of this study will inform the development of urban hydrologic fate and transport models and chloride best management practices.

Winter deicing results in substantial export of road salts to fresh waters and causes numerous ecological problems. Extension faculty and other educators at the University of Connecticut implemented New Hampshire's Green SnowPro program, a voluntary training program for salt applicators. University of Connecticut facilities staff applied 3,479 fewer metric tons of salt to campus in the 2 years after the educational training, equating to a cost savings of $459,251. Substantial environmental and economic benefits can be realized in northern climates if Extension and other educators rally behind this program.

Forum papers are thought-provoking opinion pieces or essays founded in fact, sometimes containing speculation, on a civil engineering topic of general interest and relevance to the readership of the journal. The views expressed in this Forum article do not necessarily reflect the views of ASCE or the Editorial Board of the journal.

Elevated radium (Ra) concentrations have been observed in aquifers with high naturally occurring salinity. The flux of radon (Rn) gas from the decay of Ra out of saline aquifers can be enhanced owing to salting-out effects. This raises the issue as to whether increased salinization of groundwater from road deicing practices can enhance Ra and Rn mobility to the extent that they become a human health concern. Continued use of salt (NaCl) as a road deicing agent has resulted in a gradual salinization of groundwater systems in snow-affected regions. This study presents groundwater data from a monitoring well field installed around a permeable pavement parking lot at the University of Connecticut, Storrs campus. The data suggest a connection between road salting and (a) the mobilization of dissolved Ra as well as (b) enhanced Rn gas flux from the water table. A positive correlation (R 2 = 0.92) was identified between dissolved Na+ and isotopes of Ra; a negative relationship was observed between specific conductance and dissolved Rn. In two monitoring locations, concentrations of Ra were detected that exceeded the EPA MCL of 5 pCi/L. Concentrations of Rn in the groundwater were found to be at a level that theoretically could generate gas concentrations in the vadose zone that exceed the indoor Rn standard by orders of magnitude. Given these findings, it appears that salt contamination of groundwater could increase the potential for human exposure to these radioactive and carcinogenic elements.

Bioretention has been found to treat many pollutants, but nitrogen is difficult to control. A modified bioretention system with an internal water storage zone to encourage denitrification was installed in a silage storage area at the University of Connecticut in Storrs, CT. Flow volumes were measured and flow-weighted samples were analyzed for total nitrogen (TN). The median TN concentration at the inlet was 12.3mgL-1 (mean 12.3), whereas median outlet TN concentration was 4.0mgL-1 (mean 5.1). Outlet concentrations were significantly (p<0.001) lower than inlet concentrations, with a 67.3% reduction in the median TN concentration. TN mass was reduced by 61.6%. Results indicate that this modified bioretention could be used in urban or agricultural areas to reduce N loading to receiving waters. (C) 2016 American Society of Civil Engineers.

Stormwater management is the handling and control of stormwater. Stormwater is caused by rainfall rates exceeding infiltration rates and increases with urbanization as a result of impervious surfaces such as roads, parking lots, and buildings. Stormwater best management practices (BMPs) have been developed to reduce peak flow rates and control the volume of runoff. The effectiveness of BMPs in treating stormwater quality varies with the pollutant, the BMP, the land area contributing runoff to the BMP, and the time elapsed since the previous rainfall, rainfall intensity, and many other variables.

Chloride contamination of groundwater in urban areas due to deicing is a well- documented phenomenon in northern climates. The objective of this study was to evaluate the effects of permeable pavement on degraded urban groundwater. Although low impact development practices have been shown to improve stormwater quality, no infiltration practice has been found to prevent road salt chlorides from entering groundwater. The few studies that have investigated chlorides in permeable asphalt have involved sampling directly beneath the asphalt; no research has looked more broadly at surrounding groundwater conditions. Monitoring wells were installed upgradient and downgradient of an 860m(2) permeable asphalt parking lot at the University of Connecticut (Storrs, Connecticut). Water level and specific conductance were measured continuously, and biweekly samples were analyzed for chloride. Samples were also analyzed for sodium (Na), calcium (Ca), and magnesium (Mg). Analysis of variance analysis indicated a significantly (p< 0.001) lower geometric mean Cl concentration downgradient (303.7 mg/L) as compared to upgradient (1280 mg/L). Concentrations of all alkali metals increased upgradient and downgradient during the winter months as compared to nonwinter months, indicating that cation exchange likely occurred. Despite the frequent high peaks of chloride in the winter months as well as the increases in alkali metals observed, monitoring revealed lower Cl concentrations downgradient than upgradient for the majority of the year. These results suggest that the use of permeable asphalt in impacted urban environments with high ambient chloride concentrations can be beneficial to shallow groundwater quality, although these results may not be generalizable to areas with low ambient chloride concentrations.

The Storm Water Management Model was used to simulate runoff and nutrient export from a low impact development (LID) watershed and a watershed using traditional runoff controls. Predictions were compared to observed values. Uncalibrated simulations underpredicted weekly runoff volume and average peak flow rates from the multiple subcatchment LID watershed by over 80%; the single subcatchment traditional watershed had better predictions. Saturated hydraulic conductivity, Manning's n for swales, and initial soil moisture deficit were sensitive parameters. After calibration, prediction of total weekly runoff volume for the LID and traditional watersheds improved to within 12 and 5% of observed values, respectively. For the validation period, predicted total weekly runoff volumes for the LID and traditional watersheds were within 6 and 2% of observed values, respectively. Water quality simulation was less successful, Nash-Sutcliffe coefficients >0.5 for both calibration and validation periods were only achieved for prediction of total nitrogen export from the LID watershed. Simulation of a 100-year, 24-h storm resulted in a runoff coefficient of 0.46 for the LID watershed and 0.59 for the traditional watershed. Results suggest either calibration is needed to improve predictions for LID watersheds or expanded look-up tables for Green-Ampt infiltration parameter values that account for compaction of urban soil and antecedent conditions are needed.

INTRODUCTIONIn 2007, the Connecticut Department of Energy and Environmental Protection issued the first Total Maximum Daily Load (TMDL) in the country based not on a specific pollutant or pollutants, but on impervious cover (IC) (Arnold et al., 2010). The water body in question was Eagleville Brook, a small tributary of the Willimantic River in eastern Connecticut that drains a majority of the University of Connecticut campus. The university is in effect a small city within a largely rural area. Partly as a result of this, there has been a history of "town-gown" tension and controversy with regard to the university's impact on the water resources of the area. This tension reached a climax in September 2005, when a quarter-mile stretch of the Fenton River, which drains the part of campus not in the Eagleville watershed, ran dry (Merritt, 2005). Water quantity concerns were frequently joined by water quality concerns, with area residents complaining about the pollution of their drinking water (Morse, 2002).Although the Fenton incident precipitated increased efforts on the part of the university to conserve water, efforts to improve the way that campus addressed stormwater issues lagged behind until the advent of the impervious cover TMDL. In the intervening eight years since the issuance of the "IC-TMDL" - practically the wink of an eye in the deliberate world of land use decision making - the University of Connecticut campus has become a showcase for green stormwater infrastructure (GSI) practices, also known as low impact development (LID) practices.While the IC-TMDL served as the catalyst, an environmental regulation, no matter how innovative, cannot in itself produce such dramatic change. For this to occur a number of interconnected efforts have to come together, including leadership, research, monitoring, coordination, and education both within and without the university community. This paper is an attempt to capture these key elements, consider why they worked (or didn't), and provide a status report on green stormwater infrastructure on the University of Connecticut campus.

A smart phone mobile application (app) has been created to assist landscapers, contractors and home owners in designing, installing, and maintaining rain gardens. It seeks to address water quality issues by taking advantage of the rapidly increasing use of mobile devices to access educational information and complement existing in-person educational efforts to address water quality issues. In addition to a series of tutorials, the app includes several interactive tools to help users size their garden, evaluate their soils, and select proper plants. The initial version of the app is focused on Connecticut, but a national version is planned.

Stormwater from a small municipality in Utah was monitored for flow and phosphorus. A survey was also administered to ascertain potential behavioral impacts on stormwater. The majority (53.7%) of stormwater measured was non-storm related. It is suspected that summer irrigation was adding to baseflow. Concentrations of phosphorus were below national means, but were high enough to lead to excessive algal growth. Survey results showed that most residents (92.3%) fertilize their lawn, although very few (1.7%) use a soil test to determine if fertilization is necessary. The study highlights the need for monitoring, surveying and collaboration to address current stormwater issues.

Bridgeport, Connecticut is a coastal city on Long Island Sound located in southwestern Connecticut. Bridgeport is the most populous city in the state and over 86% of the city is covered by impervious surfaces. Rainwater from storm events flows off these surfaces into rivers and streams and directly or indirectly into Long Island Sound, impacting marine habitats and organisms, water quality and human uses of the Sound and its resources. Bridgeport has recently completed several analyses and planning documents which include plans to aggressively combat climate change, and city officials are interested in partnering with Connecticut Sea Grant on a climate change adaptation strategy. Bridgeport will likely be affected by numerous climate change impacts including sea level rise, increased precipitation, and increased air and water temperatures. Over the past several decades, heavy, intense rainfall events have measurably increased in the Northeast and the frequency of such events are expected to increase even more. In order to decrease local stormwater runoff and subsequent water pollution, we have installed a 400 square foot rain garden/bioretention site on the grounds of the Bridgeport Regional Vocational Aquaculture School, that will capture and infiltrate a portion of the roof runoff. This high school is located less than 25 m from the waters of Long Island Sound. In addition to the rain garden installation, a rain garden technical training session will be held in fall 2010 for students and teachers from the Aquaculture School. A graduate student from University of Connecticut is developing an informational brochure describing the project and the link to climate change adaptation to be available at the school and at adjacent retail outlets, with the City of Bridgeport to provide signage at the site.

Bridgeport, Connecticut is a coastal city on Long Island Sound located in southwestern Connecticut. Bridgeport is the most populous city in the state and over 86% of the city is covered by impervious surfaces. Rainwater from storm events flows off these surfaces into rivers and streams and directly or indirectly into Long Island Sound, impacting marine habitats and organisms, water quality and human uses of the Sound and its resources. Bridgeport has recently completed several analyses and planning documents which include plans to aggressively combat climate change, and city officials are interested in partnering with Connecticut Sea Grant on a climate change adaptation strategy. Bridgeport will likely be affected by numerous climate change impacts including sea level rise, increased precipitation, and increased air and water temperatures. Over the past several decades, heavy, intense rainfall events have measurably increased in the Northeast and the frequency of such events are expected to increase even more. In order to decrease local stormwater runoff and subsequent water pollution, we have installed a 400 square foot rain garden/bioretention site on the grounds of the Bridgeport Regional Vocational Aquaculture School, that will capture and infiltrate a portion of the roof runoff. This high school is located less than 25 m from the waters of Long Island Sound. In addition to the rain garden installation, a rain garden technical training session will be held in fall 2010 for students and teachers from the Aquaculture School. A graduate student from University of Connecticut is developing an informational brochure describing the project and the link to climate change adaptation to be available at the school and at adjacent retail outlets, with the City of Bridgeport to provide signage at the site.

Population in Utah is projected to nearly triple in the next 50 years, to more than 6 million people. Although Utah has a small overall population compared to some other states, several regions of the state rank among the fastest growing locations in the country, with the Washington County area in the southwest corner of the state consistently ranked near the top. With massive urban growth projected, the ecological and economic benefits from sustainable development are potentially substantial. Widespread application of low impact development (LID) in Utah has been limited by many factors including lack of knowledge, institutional resistance, and policy restrictions. However, implementation of LID practices is emerging due to public and private interest in sustainable development, installation of demonstration sites, and increased guidance and training provided by local and state entities, and universities. LID is poised to be a key element in the current sustainable development push in Utah. This paper reviews the current status of LID in Utah, describes the limitations and trends, and summarizes constraints and recommendations for future LID expansion. Specific topics include infiltration practices in a large-scale development, Leadership in Energy and Environmental Design (LEED®) driving LID, overview of LID practices in Utah, and the emergence of university-led education programs to produce LID-savvy graduates in planning and engineering design.

The Utah House in Kaysville, LIT is a demonstration facility built and operated by Utah State University Cooperative Extension. It is designed to showcase alternative building techniques with a focus on, sustainable use of resources. energy and water conservation, healthy indoor air, and universal design. A Survey was sent to visitors of the Utah House in January 2008. Questions were asked about knowledge of key topics, and engagement in selected pro-environmental behaviors, to determine if their visit to the house influenced their level of knowledge or more importantly, their behavior. Significant increases in self-reported knowledge were found for all five topic areas, indicating that the house was an effective educational tool. Differences in self-reported knowledge before the visit were found for gender and educational level, but mean ratings for all groups were essentially the same after the visit. Although many visitors had already engaged in at least one pro-environmental behavior before coming to the house (83%), a large percentage (63%) made at least one change as a result of their visit, indicating that the house was a catalyst for behavior change. Although several interesting correlations were found between knowledge, feelings and behavior, no strong predictor of behavior emerged. (C) 2008 Elsevier Ltd. All rights reserved.

Development continues at a rapid pace throughout the country. Runoff from the impervious surfaces in these watersheds continues to be a major cause of degradation to freshwater bodies and estuaries. Low impact development techniques have been recommended to reduce these impacts. In this study, stormwater runoff and pollutant concentrations were measured as development progressed in both a traditional development, and a development that used low impact development techniques. Increases in total impervious area in each watershed were also measured. Regression relationships were developed between total impervious area and stormwater runoff/pollutant export. Significant, logarithmic increases in stormwater runoff and nitrogen and phosphorus export were found as development occurred in the traditional subdivision. The increases in stormwater runoff and pollutant export were more than two orders of magnitude. TN and TP export after development was 10 and 1 kg ha(-1) yr(-1), respectively, which was consistent with export from other urban/developed areas. In contrast, stormwater runoff and pollutant export from the low impact subdivision remained unchanged from pre-development levels. TN and TP export from the low impact subdivision were consistent with export values from forested watersheds. The results of this study indicate that the use of low impact development techniques on a watershed scale can greatly reduce the impacts of development on local waterways.

The low impact development (LID) approach has been recommended as an alternative to traditional stormwater design. Research on individual LID practices such as bioretention, pervious pavements, and grassed swales has increased in recent years. Bioretention cells have been effective in retaining large volumes of runoff and pollutants on site, and consistently reduced concentrations of certain pollutants such as metals. However, retention of certain pollutants such as nitrate–nitrogen and phosphorus has been problematic. Porous pavements have been extremely effective in infiltrating stormwater runoff. Concerns have been raised about groundwater contamination, but research has shown that this is not a problem in most settings. Green roofs have been found to retain a large percentage of rainfall (63% on average) in a variety of climates. A common thread across bioretention, green roofs and grassed swales was found: the export of phosphorus. The issue appears to be linked to high phosphorus levels in the soil media, or possibly to fertilization of turf or planted areas. Solutions to this problem have been recommended. Contrary to popular belief, research has shown that bioretention and pervious pavements continue to infiltrate even with frost in the ground. Although issues have been identified with retention of certain pollutants, the LID approach has been found to result in increased retention of stormwater and pollutants on site, mimicking pre-development hydrologic function. Future research needs have also been identified.