Browsing by Subject "Drinking water"
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Item Open Access A Climate and Operational Vulnerability Assessment of the Water Company in Salamanca, Chile(2017-04-28) Gochicoa, Pedro I.; Eastman, Lucas B.The present master’s project is an analysis of the future vulnerability of the water company (Aguas del Valle) in Salamanca, Chile to potential changes in population, per capita water use, leakage, and climate. Scenario modelling and sensitivity analyses were carried out in Excel and Stella. We find that under a business as usual scenario, the water company will reach maximum production capacity according to its current water rights in the year 2030. In the most pessimistic scenario, the company will reach maximum capacity in year 2025 and need to produce nearly 13 million m3 in 2050, while in the most optimistic scenario, it will not reach maximum capacity before the year 2050, and will only need to produce 510,000 m3 yearly. A detailed sensitivity analysis revealed that population growth was the principal driver of water production for the future of the water company. A Monte Carlo analysis showed that there is a 60% probability that production will be 3.4 million m3 or less in year 2050. We recommend that the company reduce leakage, which has averaged 34% over the past 10 years. We also recommend that the company invest in demand management as well as an increase in storage of the system from the 9 hours of current consumptive volume to at least 24 hours of emergency storage.Item Open Access Arsenic exposure from groundwater in Union County, North Carolina(2009-04-24T19:29:01Z) Merola, R. BrittanyArsenic contamination of groundwater is a global problem affecting human health. The highest concentrations occur overseas in areas such as Bangladesh, India, Vietnam, and Thailand. The United States is not immune and also has hotspots of arsenic in dangerously high concentrations. The focus of this project was to evaluate the extent and concentration of arsenic in one such area, Union County, North Carolina, and to attempt to use arsenic in toenails as a biomarker of exposure. Arsenic concentration above the EPA’s maximum contaminant level (MCL) of 10ppb was found in 22 out of 64 households tested (34%). The measurement of arsenic in toenails was successfully used as a biomarker of exposure. Data showed that men had a greater sensitivity to arsenic and their nail data had better correlation. Children also showed a greater sensitivity. Out of 69 participants in the toenail-biomarker study, 4 had arsenic concentrations in their toenails above a level deemed safe. Based on these results it is evident that arsenic contamination of drinking water in Union County is an issue of concern.Item Open Access ASSESSING POTENTIAL EXPOSURE TO PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN PRODUCE AND DRINKING WATER IN CHATHAM COUNTY, NC(2021-05-25) Li, Yang (Leon)Diet constitutes a major human exposure pathway for per- and polyfluoroalkyl substances (PFAS) due to the contamination of drinking water supplies, and their use in food packaging, and accumulation in the food web. Significant PFAS levels have recently been reported in groundwater (Haw River and Cape Fear River) in North Carolina. This has raised concerns for potential exposure for communities consuming drinking water sourced from these rivers and produce grown from lands irrigated with this water. This study sought to evaluate dietary exposure to PFAS from consumption of produce (lettuce, potato and tomato) and drinking water in Chatham County, North Carolina, a previously reported PFAS impacted area. A total of 18 produce samples were collected in local farmer markets and grocery stores. Drinking water PFAS data (N = 40) were abstracted from an ongoing study in Pittsboro, NC collected and analyzed in 2019 and 2020. PFAS were generally not detected in the produce samples analyzed here, with the exception of perfluorodecanoic acid (PFDA). PFDA was detected in potatoes and tomatoes, ranging from 0.11 to 1.11 ng/g, or parts per billion (ppb). Total PFAS were measured at concentrations ranging from 26.4 ng/L up to 458.1 ng/L in the drinking water samples. Using the median values of PFDA measured in produce and estimates of produce consumption in the general population (using the 50th and 95th percentiles), exposure to PFDA was estimated. Estimated exposure was highest from potato consumption (median exposure intake varies between 0.42 and 1.40 ng/kg-day). In drinking water, short-chain (<8 carbon) perfluoroalkyl carboxylate acids (PFCA) contributed the most to ∑PFAS exposure. The median exposure intake was 1.40 ng/kg-day for PFHxA and 1.17 ng/kg-day for PFPeA. Higher exposure was generally observed via drinking water compared to produce, and exposures were the highest for young children and decreased with age. The estimated hazard index suggests that a small portion of the population (~5%) could be at increased risk for adverse effects via produce exposure (in young children) and for all age groups via drinking water exposure.Item Open Access Financial Analysis of Drinking Water Systems in Shrinking Cities(2020-04-24) Bash, Rachel; Grimshaw, Walker; Horan, Kathleen; Stanmyer, Ruby; Warren, SimonCities around the country have declined in population over recent decades, creating numerous challenges in providing safe drinking water to their residents. In shrinking cities, fewer, poorer residents are left to pay for expensive infrastructure maintenance and upgrades. In this project, shrinking cities in Pennsylvania were used as case studies for declining cities across the nation. Traditional financial metrics show the financial health of struggling cities’ water utilities is stronger than expected. However, cities must make tradeoffs between strong financial health and their ability to maintain infrastructure and ensure affordable water bills. Pennsylvania’s state revolving fund could be better utilized to finance capital improvement projects at low interest rates, or even as grants to struggling cities. Cities and state agencies should work together to better use the financial and governance tools at their disposal to decrease the financial burden on shrinking cities while protecting public health and ensuring reliable access to safe drinking water.Item Open Access Great Lakes Drinking Water: A Gaps Analysis of Policy Regulation and Funding Mechanisms Supporting Safe, Affordable and Equitable Access to Drinking Water in Michigan and Wisconsin(2023-04-27) Fleck, ErinThe Great Lakes, the world’s largest freshwater resource, provide abundant freshwater to the Midwest United States, despite record-setting drought throughout the Western United States. And yet situations like the lead poisoning crisis in Flint, Michigan, and the PFAS crisis affecting the entire country continue to threaten public health across the region. An analysis of federal, state, and local drinking water management policies focused on Michigan and Wisconsin will identify gaps and challenges that exist within the current management system that prevent all Midwesterners from enjoying safe, affordable and equitable access to drinking water. Through two case studies on either side of Lake Michigan, this analysis identifies specific opportunities for improvement in both funding and regulatory mechanisms that could be implemented to better guarantee safe drinking water in the region.Item Open Access Increasing Water Affordability through a Statewide Customer Assistance Program in California(2023-04-28) Lee, JenniferCalifornia has adopted a statewide policy where “every human being has the right to clean, safe, affordable, and accessible water.” Yet having the right to clean and affordable water is not the same as having clean and affordable water. Customer assistance programs (CAP) can offer financial relief and bridge the gap to making water more affordable for everyone. Many water utilities offer rebates, subsidies, high bill adjustments, and other financial programs to help offset the cost of water utility bills. While these programs vary by water supplier, California legislators have introduced a statewide water rate assistance program. However, this bill was ultimately vetoed by the governor due to a lack of sustainable funding source. Regardless, water affordability remains an important issue and this project analyzes different options for a statewide CAP, quantifies how much it would cost, and evaluate if it is affordable for low-income households.Item Open Access Parcel Prioritization for Drinking Water Protection in the Upper Neuse River Basin, North Carolina(2007-05) Treadway, Anna R.The Upper Neuse River Basin spans six counties in the Piedmont region of North Carolina and is the drinking water source for over half a million people. This water resource needs to be protected so that it can meet the growing demand spurred by rapid population growth. Land conservation is one method for drinking water protection. The Upper Neuse Clean Water Initiative (UNCWI) has successfully prioritized parcels for conservation and suggested potential funding sources. However, they did not consider nonpoint source pollutant loads based on parcel landcover and the distance from the parcel to the surface water intakes or costs of acquiring parcels. The objective of this project is to further prioritize the UNCWI high-priorty parcels using a parcel-pollutantweighting model that considers budget constraints. There are four different scenarios of the model run based on area of the watershed and future land use scenarios. The second objective is to provide the model and results to local conservation organizations and county governments. A user-friendly Excel version of the model will be developed so that land conservationists can input their own variables for parcel prioritization to protect water quality.Item Open Access Policy Options for Financing Drinking Water Infrastructure in the United States(2013-04-25) Pepping, Troy J.Aging drinking water infrastructure in the United States is due to be replaced, with cost estimates ranging from $335 billion to more than $1 trillion over the next twenty years. Most of the financial capital will likely come from drinking water utility revenues, but there may be a role for the federal government to support infrastructure projects. Currently, the Drinking Water State Revolving Fund serves this purpose through state grants. This paper examines the current program using a regression analysis to determine which factors dictate a successful reduction in the needs of states for drinking water infrastructure. Results indicate that government funding is useful, but needs are influenced by many other demographic variables as well. A policy analysis, incorporating both quantitative and qualitative measures, compares the status quo option with two other federal policy alternatives: expanding the current program and adopting a proposed Water Infrastructure Finance and Innovation Act that would provide Treasury-backed loans directly to water utilities. Based on the policy analysis, the WIFIA proposal is the most favorable approach for the federal government. However, utility revenue will still play a large role, so water bills will assuredly increase over the coming years. The recommendation from this paper is a mix of adopting WIFIA along with other measures to soften the blow of higher water bills across the U.S., as well as further research that could examine specific case studies at the utility level.Item Open Access Potomac Watershed Priority Lands Strategy: Conserving lands to benefit drinking water quality(2009-04-24T17:09:17Z) Weidner, EmilyRapid development in the Potomac watershed – the conversion of forests to agricultural, suburban, and urban land — threatens water quality. Similarly, strategic land conservation can protect water quality. Inspired by examples of water purification through land conservation, the EPA Region 3 and the Potomac River Basin Source Water Protection Partnership (PRBSWPP) aim to prioritize areas of the Potomac watershed for conservation. To work toward this goal, I analyzed two questions: (1) How do land areas in the Potomac Watershed support stream water quality?; and (2) In a larger context, how should land conservation be prioritized to protect water quality? To assess the relationship between land use and water quality, I created a regression model to correlate land characteristics including land use composition, land use pattern, and hydrological connectivity, with water quality. The final regression shows that buffer capacity (i.e. the average percentage of downstream forest area) has the largest impact on water quality, followed by urban saturation (i.e. average percentage of downstream urban area), and two estimates of soil loss and erodibility. I mapped the output of this regression analysis. To identify priority lands for conservation, I developed a multi-object decision analysis (MODA) tool. I used the weighted averaging approach to combine a land parcel’s water quality protection value, water intake protection value, and ecological value, along with its vulnerability to future development. This resulted in a map showing areas of higher and lower conservation priority, which can be used to allocate funds for conservation, update local zoning to designate strategically located natural areas, assist developers in minimizing their environmental impact, and strengthen coalitions in developing a common understanding of the multiple benefits of land conservation.Item Open Access Private Water Utility Landholdings: Financial and Political Implications(2014-04-25) Vigliotti, TabithaEcosystem services research has led to policies favoring watershed land protection at the federal, state, local, and private levels, notably at drinking water treatment facilities. A few researchers have connected land use and water utilities by estimating surface water treatment costs through raw water sediment load. However, more comprehensive cost-benefit research of private watershed land ownership is absent. In my research, I develop a distributional cash flow model to estimate the magnitude and timing of costs and benefits to a Connecticut private water company, the local community, and to the economy as a whole using Connecticut Public Utilities Regulatory Authority data, interviews, regulatory landscape, tax regime, and non-market valuation benefits transfer. The base case model predicts positive NPV to all parties in Connecticut: $3,828,432,329 to the economy from 2010 through 2025, where $1,461,824,087 of that is from benefits to the company and $2,366,608,242 is from benefits to the community. Sensitivity analysis implies these findings may be robust to systematic changes (+/- 10% and +/-20%) to input parameters. The distribution of costs and benefits lends itself to political economy considerations and future policy reflections.