Syllabus: Drinking Water, Sanitation, and Global development

Within the past three decades, more than 2.6 billion people have gained access to an improved water source and 2.1 billion have gained access to an improved sanitation facility. However, improved does not always mean people have safe, reliable, accessible, or equitable water and sanitation services. Waterborne diseases continue to cause and estimated 500,000 deaths each year. What causes waterborne diseases, and what is the role of engineered systems in their spread or prevention? How can we evaluate interventions to improve health and well-being? How can research address these challenges

Dry Pipes: Associations between Utility Performance and Intermittent Piped Water Supply in Low and Middle Income Countries

Abstract Intermittent piped water supply impacts at least one billion people around the globe. Given the environmental and public health implications of poor water supply, there is a strong practical need to understand how and why intermittent supply occurs, and what strategies may be used to move utilities towards the provision of continuous water supply. Leveraging data from the International Benchmarking Network for Water and Sanitation Utilities, we discover 42 variables that have statistically significant associations with intermittent water supply at the utility scale across 2115 utilities. We categorized these under the following themes: Physical infrastructure system scale, coverage, consumer type, public water points, financial, and non-revenue water and metering. This research identifies globally relevant factors with high potential for cross-context, scaled impact. In addition, using insights from the analysis, we provide empirically grounded recommendations and data needs for improved global indicators of utility performance related to intermittent supply

Rain Rain Flush Away: Evaluating Rainwater Catchment First Flush Volumes

Rainwater harvesting systems often include quality control systems such as a diverted first flush volume to improve the collected water quality. The first flush volume has traditionally been defined as a set volume of rain based on the first 1-2 millimeters of rain that falls on a roof. Diverting a volume of water can be seen as a waste when rainwater is a main source of potable water, sometimes leading to lack of implementation, and thus contaminating the final collected water. Understanding the variability of first flush volume required due to environmental parameters can be used to develop an optimized first flush system. This study evaluated rainwater catchment first flush volumes by assessing the rainwater quality over volume and time. To study these effects, we built a rainwater collection system on a test site in Amherst, Massachusetts. We performed a tracer study with the rainwater collection system to model the first flush volume required to wash out a dissolved contaminant. We collected four rain events using a fractionation first flush design. We measured water quality parameters in the atmospheric rain, first flush, and collection tank samples for each rain event. Our first flush samples resulted in elevated dissolved organic carbon (DOC) concentrations up to 40 mg/L, although there was high variation between the rain events. UV 254, DOC, and conductivity all trended together within each rain event, demonstrating a uniform wash off, of contaminants. Indicator bacteria up to 200 MPN/100 mL within rain event 1 and 2, indicates the need for disinfection if the water is to be potable. The high levels of DOC and SUVA characterization presented a concern for disinfection by-products (DBP) potential if the water were treated with chlorine. Higher intensity storms seem to increase roof wash-off deposition in the first flush. The majority of contaminants washed off in the first flush seemed to originate from roof wet and dry deposition, demonstrating the need for variable first flush volumes. Hydraulic parameters that affect wash-off, such as rain intensity and collection location, also led to varied first flush volumes. Considering these factors in the first flush volume required, could decrease treatment needs, system maintenance, and concern from treatment by-products

Measuring the Impacts of Water Safety Plans in the Asia-Pacific Region

This study investigated the effectiveness of Water Safety Plans (WSP) implemented in 99 water supply systems across 12 countries in the Asia-Pacific region. An impact assessment methodology including 36 indicators was developed based on a conceptual framework proposed by the Center for Disease Control (CDC) and before/after data were collected between November 2014 and June 2016. WSPs were associated with infrastructure improvements at the vast majority (82) of participating sites and to increased financial support at 37 sites. In addition, significant changes were observed in operations and management practices, number of water safety-related meetings, unaccounted-for water, water quality testing activities, and monitoring of consumer satisfaction. However, the study also revealed challenges in the implementation of WSPs, including financial constraints and insufficient capacity. Finally, this study provided an opportunity to test the impact assessment methodology itself, and a series of recommendations are made to improve the approach (indicators, study design, data collection methods) for evaluating WSPs

From data to decisions: understanding information flows within regulatory water quality monitoring programs

Most countries maintain regulatory requirements for testing of drinking water supplies to guide treatment procedures and ensure safe water delivery to consumers. It is unclear, however, if water quality data are always used effectively, particularly in low-resource settings. Efforts to improve the use of water quality data will benefit from a comprehensive understanding of existing systems for managing and sharing information. This study evaluates the methods used to organize, analyze, and transmit drinking water quality data among 26 water supplier or surveillance institutions and two regulatory agencies in six countries of sub-Saharan Africa. Following extensive qualitative and quantitative data collection, we developed data flow diagrams to map formal and informal water quality networks. We found high levels of similarities between the information systems established by different institutions operating under different regulatory structures. We determined that the key barriers to information flows were the limited aggregation and analysis of data and the poor enforcement of data sharing requirements. Our results suggest that broad reforms are necessary to improve the use of these water quality data to manage water safety. These measures could include strengthening enforcement of testing and reporting, building staff capacity for managing and using data, and integrating collection of water quality data with other information systems

Measuring the Impacts of Water Safety Plans in the Asia-Pacific Region

This study investigated the effectiveness of Water Safety Plans (WSP) implemented in 99 water supply systems across 12 countries in the Asia-Pacific region. An impact assessment methodology including 36 indicators was developed based on a conceptual framework proposed by the Center for Disease Control (CDC) and before/after data were collected between November 2014 and June 2016. WSPs were associated with infrastructure improvements at the vast majority (82) of participating sites and to increased financial support at 37 sites. In addition, significant changes were observed in operations and management practices, number of water safety-related meetings, unaccounted-for water, water quality testing activities, and monitoring of consumer satisfaction. However, the study also revealed challenges in the implementation of WSPs, including financial constraints and insufficient capacity. Finally, this study provided an opportunity to test the impact assessment methodology itself, and a series of recommendations are made to improve the approach (indicators, study design, data collection methods) for evaluating WSPs

Water Quality and Quantity in Intermittent and Continuous Piped Water Supplies in Hubli-Dharwad, India

In at least 45 low- and middle-income countries, piped water systems deliver water for limited durations. Few data are available of the impact of intermittent water supply (IWS) on the water quality and quantity delivered to households. This thesis examines the impact of intermittently supplied piped water on the quality and quantity of water delivered to residential taps in Hubli-Dharwad, India, when compared to continuous piped water supply. A framework for understanding the pathways through which IWS can impact water quality is first developed. The extent to which contamination occurs in Hubli-Dharwad is quantified by comparing microbial water quality throughout the distribution system in an intermittent system and a continuous system in the same city. The mechanisms affecting water quality in the IWS network in Hubli-Dharwad are identified by measuring changes in water quality over time using continuous measurements from pressure and physico-chemical sensors paired with grab samples tested for indicator bacteria. In the final chapter, a new method of measuring household water consumption in an IWS when supply durations are limited and few metered data are available is developed. This thesis showed that the intermittent supply was frequently subject to contamination in the distribution system and that households with intermittent supply consumed limited quantities of water. While these results demonstrated that converting to a continuous water supply can improve water quality when compared to intermittent supply, this conversion may not be possible in the near future for resource-constrained towns and cities. This thesis contributes to knowledge of the mechanisms causing contamination and constricting water access in IWS systems, which can help improve systems to ensure that people with piped water receive water that is reliable, safe, and sufficient

Water Quality and Quantity in Intermittent and Continuous Piped Water Supplies in Hubli-Dharwad, India

In at least 45 low- and middle-income countries, piped water systems deliver water for limited durations. Few data are available of the impact of intermittent water supply (IWS) on the water quality and quantity delivered to households. This thesis examines the impact of intermittently supplied piped water on the quality and quantity of water delivered to residential taps in Hubli-Dharwad, India, when compared to continuous piped water supply. A framework for understanding the pathways through which IWS can impact water quality is first developed. The extent to which contamination occurs in Hubli-Dharwad is quantified by comparing microbial water quality throughout the distribution system in an intermittent system and a continuous system in the same city. The mechanisms affecting water quality in the IWS network in Hubli-Dharwad are identified by measuring changes in water quality over time using continuous measurements from pressure and physico-chemical sensors paired with grab samples tested for indicator bacteria. In the final chapter, a new method of measuring household water consumption in an IWS when supply durations are limited and few metered data are available is developed. This thesis showed that the intermittent supply was frequently subject to contamination in the distribution system and that households with intermittent supply consumed limited quantities of water. While these results demonstrated that converting to a continuous water supply can improve water quality when compared to intermittent supply, this conversion may not be possible in the near future for resource-constrained towns and cities. This thesis contributes to knowledge of the mechanisms causing contamination and constricting water access in IWS systems, which can help improve systems to ensure that people with piped water receive water that is reliable, safe, and sufficient

Dry Pipes: Associations between Utility Performance and Intermittent Piped Water Supply in Low and Middle Income Countries

Intermittent piped water supply impacts at least one billion people around the globe. Given the environmental and public health implications of poor water supply, there is a strong practical need to understand how and why intermittent supply occurs, and what strategies may be used to move utilities towards the provision of continuous water supply. Leveraging data from the International Benchmarking Network for Water and Sanitation Utilities, we discover 42 variables that have statistically significant associations with intermittent water supply at the utility scale across 2115 utilities. We categorized these under the following themes: Physical infrastructure system scale, coverage, consumer type, public water points, financial, and non-revenue water and metering. This research identifies globally relevant factors with high potential for cross-context, scaled impact. In addition, using insights from the analysis, we provide empirically grounded recommendations and data needs for improved global indicators of utility performance related to intermittent supply