2015 AWRA Spring Conference: Water for Urban Areas: Managing Risks and Building Resiliency
Poster Sessions

Monday, March 30 - Tuesday, April 1, 2015

Posters will be on display Monday, from 8:30 AM - 6:30 PM (Poster Presenters will be at their posters from
5:00 PM - 6:30 PM during the Opening Networking Reception) and Tuesday from 8:30 AM - 3:30 PM

Note: The Presenter of each poster is in BOLD type immediately following the poster title. Co-authors are then listed in parentheses.

San Francisco Public Utilities Commission Sustainable Management of Groundwater Resources in the North Westside Basin - Carolyn Cooper, San Francisco Public Utilities Commission, San Francisco, CA (co-authors: H, Shannon, N. Johnson, C. Altare)

In 2014, the San Francisco Public Utilities Commission (SFPUC) began preparation of a Groundwater Management Plan (GMP) for the North Westside Basin (NWB), consistent with Assembly Bill 3030 and California Water Code (CWC) Sections 10750 et seq. The purpose of the NWB GMP is to guide management and implementation of sustainable groundwater resources projects to meet existing and future demand. The NWB is overlain by the City and County of San Francisco (CCSF) and extends north from the San Mateo County line south of Lake Merced and includes most of Golden Gate Park. The CCSF, through the SFPUC, owns and operates a regional water system that extends from the Sierra Nevada to the City of San Francisco (City) and serves 2.6 million customers in San Francisco, San Mateo, Santa Clara, and Alameda counties. The source of water for retail and wholesale customers is mostly imported surface water augmented with relatively minor contributions from local supplies. During preparation of the GMP, California's Sustainable Groundwater Management Act (SGWMA) was signed into law. In an effort to proactively manage groundwater resources within the NWB, SFPUC plans to develop a Groundwater Sustainability Plan (GSP) consistent with the new legislation. The new legislation requires GSPs to include a sustainability goal as well as measurable objectives and interim milestones to track progress of meeting those objectives. Development of the GSP will involve a stakeholder process to engage neighboring groundwater users in the development of consistent methodologies and use of the same data for GSPs within the same groundwater basin, as defined by the California Department of Water Resources. The SFPUC has initiated discussions with neighboring groundwater users and intends to develop agreements with those users forming Groundwater Sustainability Agencies (GSA) within the basin per the SGWMA. The GSP will provide a framework for how SFPUC will sustainably manage groundwater in the NWB through implementation of actions and groundwater projects to meet measurable objectives. In the NWB, implementation of the SFPUC Groundwater Supply Project will be consistent with the GSP and will be implemented to reduce dependence on imported surface water and create a more reliable water supply.

The Unreliable Supply of Urban Water for Lagos. Nigeria - Longinus Ugochukwu Enyeribe Iwuh, Kolej Gemilang, Mantin, Nigeria(co-authors: T. J. Deepak, M. M. H. Khan)

The water infrastructure in Lagos is more than 70 years old and lacks adequate construction. Due to poor maintenance and considering its age, it is damaged with bacterial decay. Lagos water sector is a zone of serious lapse. Lagos is a Metropolitan region with a population of over 21 million people. Naturally, considering the population magnitude, the supply of water is consistently on high demands, both due to large population and large per capita use and waste. In addition to the crippled water infrastructure in Lagos, the local/traditional sources of water like rivers, lakes, tanks and in many cases even ground water have been depleted, polluted or destroyed as a result of industrial activities in the city. Rainfall is generally seen as a calamity rather than a benefaction as it brings floods because the drainage systems are poorly designed. Consequently, water demand shortages are sure to develop. These demand shortages are predicted to intensify to new levels in the nearest decade should measures are not performed to curb these increasing risks. The purpose of this research are in five-folds

1- To accurately determine the details of the water infrastructure of Lagos Metropolitan region in Nigeria so as to form an explanation for the future.
2- To actuate where the water of Lagos is being supplied and how the water is distributed.
3- To know the problems associated with the present water supply and distribution method
4- To reveal how an increase in human population poses a threat to urban water supply
5- Finally, to provide initiatives that can be implemented to help mitigate the uncertain supply of water in Lagos and carefully ensure long-term management.

This research adopted different methods to gather reliable data. To understand the problem of water supply in Lagos Metropolitan region, it was crucial to calculate how much fresh water is needed per one person within a region in Lagos called Maryland. A questionnaire was prepared using Water Footprints. It was discovered that an average Lagosian requires 2.5 cubic meters of fresh water per day. Ironically, from the water suppliers' data, it is estimated to supply 1.3 cubic meters of water daily per person. This supply-demand in balance is the major cause of the water demand shortage. With the population of Lagos expected to grow by 15% in the nearest decade, the supply of water and its management will certainly become a major issue. The current water supply system in Lagos is faulty and leads to demand shortages. Application of new improved methods of supply systems and desalination will help prevent shortages of water and increases availability. Furthermore, Government officials of Lagos state in Nigeria should form appropriate policies and invest more in the infrastructure of water supply.

Understanding Urban Water Resources in the Bay Area and Opportunities for Enhanced Water Reliability - Patricia Gonzales, Stanford University, Stanford, CA (co-authors: N. Ajami, R.G. Luthy)

Traditional water supply portfolios have proven to be unreliable for addressing today's urban water challenges. New water sources such as recycling and reuse, stormwater and rainwater capture, and desalination as well as demand management scenarios such as leak reduction and conservation, can introduce more flexibility and resiliency to the local water systems under the uncertainties of growth and climate change. Innovative management approaches are required to introduce this kind of flexibility to the existing system. In particular, the implementation of projects enhancing local supplies, coupled with regional coordination could develop mutually beneficial solutions that take into consideration the different needs and perspectives of all entities involved. In this initial case study we look at the Bay Area Water Supply and Conservation Agency (BAWSCA), an existing coordinating agent of 26 service areas sharing a common resource pool from the San Francisco regional water system. This work describes the current state of the water system, evaluates potential water augmentation projects, and maps the current network of water resources and inter-agency collaborations at various scales in the BAWSCA service area. Preliminary results show that even small water agencies are starting to outgrow their allocated supplies. Even though per-capita demand seems to be decreasing, total demand projections show a gap in the current supply portfolios. This indicates that Bay Area water agencies are in a position to consider local supplies to supplement their current portfolios. The different demand sectors present an opportunity for matching supply sources of different quality levels to non- potable uses. Furthermore, as imported water prices continue to increase, investments in local supplies and inter-agency collaborations may become more appealing and financially feasible. Our initial analysis incorporates data from past and present water resources, as well as conservation efforts and the potential for water recycling and reuse. This research aims to understand the diversity of supply and demand portfolios in the Bay Area, identify trends and connections between the agencies, and evaluate flexibility points where new supply sources could be introduced. Making this information available to water agencies could lead to identifying effective management strategies at both local and regional scales, thus enhancing the reliability, flexibility, and resiliency of the system as a whole.

Study of the Urban Water Environment (UWE): A Framework for Predicting and Assessing Urban Shallow Groundwater Contamination by Sanitary Sewer Exfiltration - Do Gyun Lee, University of California, Santa Barbara, Santa Barbara, CA (co-authors: D. G. Lee, P. R. Roehrdanz, M. Feraud, J. Ervin, T. Anumol, A. Jia, M.Park, C. Tamez, E. W. Morelius, J. L. Gardea- Torresdey, J. Izbicki, J. C. Means, S. A. Snyder, P. A. Holden)

In urban areas, shallow groundwater is vulnerable to contamination from human activity due to its proximity to many potential contamination sources, including leaking public sewers, irrigation with reclaimed water, or stormwater. Because shallow groundwater is linked to surface waters within the hydrologic system, contaminated shallow groundwater can also transport pollutants into surface water bodies and thereby impact human health or aquatic life. Shallow groundwater pollution may also threaten the water quality of deeper confined aquifers that serve as more immediate emergency water sources. Thus, understanding pollution and its sources into shallow groundwater is important for many reasons. Previous research in the subject city has confirmed contamination of dry weather storm drain flow and surface waters as a result of leaking sewer pipes. Therefore, untreated sewage leaks may be a significant shallow groundwater pollution source in the subject city and in other cities with aging sewer infrastructure. However, neither the magnitude of contamination nor the risks of sewage exfiltration from degraded sewer lines is currently well defined in our study area. The overall purpose of this project is to develop an analytical framework to assess the evidence for untreated sewage leaking into shallow groundwater. Additionally, we sought to determine if patterns of contamination are predictable by a GIS based model of exfiltration probability that we have developed. Initial results of this study show that shallow groundwater in selected locations was impacted by less than 1% of sewage equivalent contamination and that the GIS-based model strongly related to wastewater-associated compounds and fluorescence spectroscopy of dissolved organic matter (DOM). Additionally, out of the 178 organic analytes initially surveyed, eleven organic compounds were determined to be the suitable indicators of wastewater impact in shallow groundwater. This study demonstrated the potential for a geospatial model of sewer exfiltration probability, coupled with fluorescence spectroscopy of DOM and targeted organic analytes, as a framework to identify locations of degraded sewage infrastructure that may enable release of sewage to urban shallow groundwater. To validate the framework proposed in this study and to provide a more complete representation of shallow groundwater contamination in the subject city, an expanded study was recently completed. This study included wells placed in areas where shallow groundwater is the most likely to be contaminated by wastewater exfiltration based on the GIS model. Results from this broader sampling will be used to determine the level of wastewater- associated contamination in urban shallow groundwater and to define a generalized framework that can be used as a management support tool for sanitary sewer leakage investigation and infrastructure replacement in other cities.

Climate Change Impacts on Green Infrastructure Performance in Toledo - Hassan Tavakoldavani, University of Utah, Salt Lake City, UT (co-authors: E. Goharian, C. Hansen, H. Tavakol-Davani, S. Burian)

Combined Sewer Overflow (CSO) controls are conventionally designed based on historical climate data. However, recent climate change studies emerged that stormwater infrastructure, within the built environment, may need to meet new performance expectations under future climatic conditions. This research simulated the impacts of climate change on rainfall intensities, and through rainfall-runoff modeling, studied the impacts on CSO volumes, frequency and duration. The effectiveness of Green Infrastructure (GI) and their potential to mitigate the climatic changes were also compared under different precipitation scenarios. Combined sewer network of the City of Toledo, Ohio was the focus of the research. CSOs and GIs were modeled through the United States Environmental Protection Agency Storm Water Management Model version 5.1 (EPA SWMM5.1). Rainfall-runoff simulations were driven based on modified historical precipitation to represent future projections achieved through the Coupled Model Intercomparison Project Phase 5 (CMIP5). Lastly, a GI plan consisting of rainwater harvesting systems, porous pavements and bio- retention cells was designed based on site feasibility, and then evaluated using the developed model.

Temporal structure of streamflow records from urban basins: What does it has in common with heart disease? - Tijana Jovanovic, The Pennsylvania State University, University Park, PA (co]author: A. Mejia)

The analyses of streamflow records from urban basins have emphasized metrics that characterize short]term
behavior. These analyses include, but are not limited to, studying event driven hydrological responses,
quantifying high and low flow conditions, measuring the degree of streamflow variability and the fraction of
streamflow above a specified threshold, and assessing changes in the overall distribution of streamflow
magnitudes. On the other hand, the analysis of long]term behavior has been constrained to evaluating the
existence and magnitude of trends while changes in the temporal structure of the signal have been neglected. In
contrast with previous studies, our main goal here is to evaluate the long]term temporal behavior of streamflow
records form urban basins. To achieve this, we analyze the streamflow records from 22 urban basins in the
metropolitan areas of the cities of Baltimore, Philadelphia, and Washington DC, USA, using statistical measures
for complex time series which can account for nonstationary and nonlinear conditions. From the application of
these measures, results indicate that the long]term persistence and complexity of streamflow records is reduced
for the most urbanized basins. Since the emphasis of stormwater management has primarily been on
streamflow magnitudes, the influence of changes in the long]term temporal structure of streamflow on stream
health is poorly known. This issue may be worth exploring further as it is possible to maintain or restore the
distribution of streamflow magnitudes while modifying their temporal structure.

Water Footprint of Cities: A Review and Case Study for Philadelphia - Willa Paterson, The Pennsylvania State
University, University Park, PA (co]authors: R. Ikechukwu, C. Ahams, A. Mejia)

Cities are hotspots of commodity consumption, with implications for non]local water resources. Water flows
virtually into cities through this commodity exchange, meaning that local water issues have a global context.
This form of water eteleconnectionf is being increasingly recognized as an important aspect of water decision
making at the national scale. In cities and urban areas, virtual water flows are rarely acknowledged. The
emphasis is on the physical and engineered water balances. We perform an extensive literature review of water
footprint studies in order to evaluate the potential and importance of taking virtual flows into account in cities
and a case study for Philadelphia is presented to understand these flow dynamics. We also compare and
contrast current methods to assess virtual water flows. Specifically, we examine the Water Footprint Network
method, life cycle assessment, and environmentally extended input]output method. Lastly, key themes are
identified, such as the urban metabolism and water scarcity, and are discussed as complementary frameworks
for water footprint analysis.