Long-Range Planning for Water Reuse in the City of Los Angeles

1991 ◽  
Vol 24 (9) ◽  
pp. 11-17 ◽  
Author(s):  
Bahman Sheikh
Keyword(s):  
Los Angeles ◽  
Groundwater Recharge ◽  
Water Reuse ◽  
Potable Water ◽  
Reclaimed Water ◽  
Potable Reuse ◽  
Water Demands ◽  
San Fernando ◽  
Near Term

While new sources of affordable potable water for Los Angeles will likely decrease or be unavailable in the future, sources of readily usable reclaimed water will double over the next decade. For many non-potable uses (e.g., landscape irrigation, industrial cooling, toilet flushing), reclaimed water can replace potable water, thereby making equivalent volumes of potable water available. Groundwater recharge with reclaimed water can further augment potable water supplies in significant volumes. Quantitative goals for water reuse were derived by comparing projected water demands with predicted dependable supplies. These goals are to reuse 40, 70, and 80 percent of the total effluent by the years 2010, 2050, and 2090, respectively. In this planning study, several water reuse concepts were evaluated for near-, mid-, and long-term application. For the near-term, several immediately implementable water reuse projects are recommended, involving landscape irrigation, industrial cooling and groundwater recharge. For the mid-term, massive groundwater recharge in San Fernando Valley and in Central and West Coast Basins is recommended. For the long-term, potable reuse and/or groundwater recharge appear to be the best options.

A Review of Water Reuse and Recycling, with Reference to Canadian Practice and Potential: 2. Applications

2004 ◽  
Vol 39 (1) ◽  
pp. 13-28 ◽  
Author(s):  
Kirsten Exall
Keyword(s):  
Groundwater Recharge ◽  
Water Reuse ◽  
Municipal Wastewater ◽  
Reclaimed Water ◽  
Potable Reuse ◽  
Industrial Sectors ◽  
The World ◽  
Housing Corporation ◽  
Indirect Potable Reuse ◽  
Treated Municipal Wastewater

Abstract Common water reuse applications include agricultural and landscape irrigation with treated municipal wastewater, industrial recirculation of process waters, rainwater collection, and groundwater recharge for non-potable and indirect potable reuse. As compared to other countries worldwide, water reuse is currently practised infrequently in Canada, with the focus of most of the water reuse effort within Canada on agricultural irrigation applications. Landscape irrigation and other non-potable urban uses are practised to some extent, but provide an opportunity for expanded application of reclaimed water. Similarly, while water recycling is practised to various degrees within specific industrial sectors, further industrial water reuse and recycling affords an opportunity to conserve large volumes of water. The Canada Mortgage and Housing Corporation (CMHC) has supported a great deal of research into treatment and reuse of domestic greywater for non-potable uses within individual buildings, as well as some work on rainwater collection and use. Groundwater recharge and potable reuse are practised to some extent in extremely dry regions of the world, but public health concerns with respect to emerging trace contaminants may limit the spread of these reuse applications. The main issues associated with each of the above applications are reviewed, and the state of Canadian water reuse and recycling is described.

scholarly journals Human Health Impact of Cross-Connections in Non-Potable Reuse Systems

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1352 ◽  
Author(s):  
Mary Schoen ◽  
Michael Jahne ◽  
Jay Garland
Keyword(s):  
Potable Water ◽  
Reclaimed Water ◽  
Water System ◽  
Health Impact ◽  
Quantitative Microbial Risk Assessment ◽  
Pathogen Inactivation ◽  
Microbial Infection ◽  
Microbial Risk Assessment ◽  
Potable Reuse ◽  
Contamination Event

We used quantitative microbial risk assessment (QMRA) to estimate the microbial risks from two contamination pathways in onsite non-potable water systems (ONWS): contamination of potable water by (treated) reclaimed, non-potable water and contamination of reclaimed, non-potable water by wastewater or greywater. A range of system sizes, event durations, fraction of users exposed, and intrusion dilutions were considered (chlorine residual disinfection was not included). The predicted annual microbial infection risk from domestic, non-potable reuse remained below the selected benchmark given isolated, short-duration intrusion (i.e., 5-day) events of reclaimed water in potable water. Whereas, intrusions of wastewater into reclaimed, non-potable water resulted in unacceptable annual risk without large dilutions or pathogen inactivation. We predicted that 1 user out of 10,000 could be exposed to a 5-day contamination event of undiluted wastewater in the reclaimed, non-potable water system each year to meet the annual benchmark risk of 10−4 infections per person per year; whereas, 1 user out of 1000 could be exposed to a 5-day contamination event of undiluted reclaimed water in the potable water each year. Overall, the predicted annual risks support the use of previously derived non-potable reuse treatment requirements for a variety of ONWS sizes and support the prioritization of protective measures to prevent the intrusion of wastewater into domestic ONWS.

Source water impact model (SWIM) - a watershed guided approach as a new planing tool for indirect potable water reuse

2001 ◽  
Vol 43 (10) ◽  
pp. 267-275 ◽  
Author(s):  
J. E. Drewes ◽  
P. Fox
Keyword(s):  
Water Quality ◽  
Water Reuse ◽  
Reclaimed Water ◽  
Water Sources ◽  
Distribution Data ◽  
Source Water ◽  
Impact Model ◽  
Water Impact ◽  
Potable Reuse ◽  
The Impact

The scope of this study was to develop a model to assess the impact of source water quality on reclaimed water used for indirect potable reuse. The source water impact model (SWIM) considered source water qualities, water supply distribution data, water use and the impact of wastewater treatment to calculate reclaimed water quality. It was applied for sulfate, chloride, and dissolved organic carbon (DOC) at four water reuse sites in Arizona and California. SWIM was able to differentiate between the amount of salts derived by drinking water sources and the amount added by consumers. At all sites, the magnitude of organic residuals in reclaimed water was strongly effected by the concentration of organics in corresponding water sources and effluent-derived organic matter. SWIM can be used as a tool to predict reclaimed water quality in existing or planned water reuse systems.

scholarly journals Five-century record of climate and groundwater recharge variability in southern California

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
F. Manna ◽  
K. M. Walton ◽  
J. A. Cherry ◽  
B. L. Parker
Keyword(s):  
Los Angeles ◽  
Groundwater Recharge ◽  
Southern California ◽  
Surface Soil ◽  
Time Interval ◽  
Chloride Salt ◽  
Freshwater Flow ◽  
The Pacific ◽  
Salt Distribution

AbstractModifications to the rates of water flowing from the surface to groundwater (groundwater recharge) due to climate variability are the most difficult to assess because of the lack of direct long-term observations. Here, we analyze the chloride salt distribution below the surface soil on a plateau near Los Angeles to reconstruct the amount of recharge that occurred in the last five centuries. Over this time interval, periods of major high and low recharge with different duration follow each other and this cyclicity is consistent with long-term atmospheric forcing patterns, such as the Pacific Decadal Oscillation. This study determines the range and the natural variability of recharge to groundwater, which sustains local freshwater flow system, and helps forecast future availability of groundwater resource in southern California, where water scarcity is critical to both local and global populations.

Advancing indirect potable reuse in California

2013 ◽  
Vol 8 (2) ◽  
pp. 275-285 ◽  
Author(s):  
G. D. Wetterau ◽  
R. B. Chalmers ◽  
P. Liu ◽  
W. Pearce
Keyword(s):  
Los Angeles ◽  
Potable Water ◽  
Treatment Process ◽  
Orange County ◽  
Pilot Scale ◽  
Full Scale ◽  
Lessons Learned ◽  
Potable Reuse ◽  
Indirect Potable Reuse ◽  
Publicly Supported

While indirect potable reuse (IPR) has been used in southern California (USA) since the 1970s, the commissioning of the 265-megalitre-per-day Groundwater Replenishment System (GWRS) in Orange County (California) showed the region's commitment to utilizing reuse as a major source of potable water augmentation. The treatment process used at GWRS has become the benchmark on which California regulations were based and which other IPR facilities are measured against. As the cities of Los Angeles and San Diego move forward with their own IPR programs, they have commissioned pilot-scale and demonstration-scale projects to build on the lessons learned at the GWRS and to aid in developing future projects that are efficient, effective, and publicly supported. This paper will discuss the technical approaches being evaluated in these projects and the lessons learned in the operation of the existing full-scale facilities.

scholarly journals Toilet power: potable water reuse and the situated meaning of sustainability in the southwestern United States

2019 ◽  
Vol 26 (1) ◽  
pp. 633
Author(s):  
Kerri Jean Ormerod
Keyword(s):  
United States ◽  
Water Reuse ◽  
Q Methodology ◽  
Potable Water ◽  
Urban Metabolism ◽  
Urban Wastewater ◽  
Southwestern United States ◽  
Potable Reuse ◽  
Contextual Understanding ◽  
Direct Potable Reuse

<p>Proposals to recycle urban wastewater for potable purposes are at the forefront of water development. In this article I combine political ecology's attention to networked relations with Q methodology to identify the shared positions of select stakeholders in the southwestern United States, an urbanizing region increasingly reliant on potable water reuse. I employ critical Q methodology to provide a contextual understanding of how water and sanitation technology shapes subjects and environments. The analyses reveal two distinct sanitary subjectivities, which I label neosanitarian and ecosanitarian, whose views most sharply diverge regarding the appropriateness of direct potable reuse and composting toilets. The findings highlight the situated meaning of sustainability and also underscore the role that wastewater and water reuse play in shaping ecologies, which in turn, helps to identify the environments of elimination that make specific innovations in the water sector possible. In conclusion, I suggest that in the broader context of potable water reuse, the toilet is in a perniciously powerful position to make city-spaces and shape the future citizenry.</p><p><strong>Keywords</strong>: infrastructure, urban metabolism, Q methodology, water recycling, composting toilet</p>

Salt content of reclaimed water from sanitation facilities in informal settlements and management options for sustainable agricultural irrigation

2015 ◽  
Vol 10 (1) ◽  
pp. 99-109
Author(s):  
K. Müller ◽  
P. Cornel
Keyword(s):  
Water Reuse ◽  
Membrane Filtration ◽  
Root Zone ◽  
Tap Water ◽  
Salt Content ◽  
Reclaimed Water ◽  
Management Options ◽  
Urine Separation ◽  
Per Capita

For long-term sustainable irrigation of agricultural areas, salt accumulation on the fields needs to be controlled. In areas where rainfall is high at least during some time of the year, infiltrating water is usually sufficient to leach salts from the soil. In arid and semi-arid regions, rainfall might be too scarce, and additional measures for the removal of salts from the root zone are necessary. This paper presents data on water quantities, electrical conductivity (EC), and total dissolved solids (TDS) from a research project with agricultural water reuse in North Namibia and discusses options for salinity management. During planning, TDS were quantified using literature data. After implementation, quantities, EC, and TDS of tap water and reclaimed water were monitored. Mean water consumption is 61–64 L per capita equivalent and day. TDS loads are about 20–21 g/(capita equivalent × d) and thus lower than reported in literature. TDS loads in the water can be reduced by measures such as urine separation or reverse osmosis membrane filtration. However, accumulation on the field is still considerable in the long term. Salt uptake in crops is only substantial to the salt balance if TDS contents of the irrigation water are relatively low. Therefore, in the majority of cases, regular drainage and leaching of the fields are necessary. The per capita TDS loads and water quantities presented in this work are specific results collected from the facilities implemented in this project. They can serve as a basis for estimating water quantities and excreta loads for similarly managed sanitation facilities.

On-site water recycling systems in Japan

2003 ◽  
Vol 3 (3) ◽  
pp. 149-154 ◽  
Author(s):  
H. Yamagata ◽  
M. Ogoshi ◽  
Y. Suzuki ◽  
M. Ozaki ◽  
T. Asano
Keyword(s):  
Water Supply ◽  
Water Reuse ◽  
Potable Water ◽  
Reclaimed Water ◽  
Urban Water ◽  
Water Recycling ◽  
Technical Problems ◽  
Recycling System ◽  
Site Water ◽  
Recycling Systems

Non-potable urban water reuse is Japan's main water reuse practice, which includes water for environmental uses, in-stream flow augmentation, toilet flushing, and industrial reuse. On-site water recycling systems reclaim wastewater on site as well as harvest rainwater in one or more large buildings and distributing the reclaimed water within the buildings for non-potable reuse. Based on our survey conducted in 1999 on current status of on-site water recycling systems in 23 wards of the Tokyo Metropolitan Government District, the following findings are reported in this paper: (1) on the average, 61% of non-potable water demand is met by reclaimed water, and the deficit is made up by tap water from city water supply, (2) biological treatment or ultrafiltration processes can provide reliable treatment and suitable water quality. Some technical problems such as odor from on-site treatment facilities have occurred in a few buildings, (3) there has been no serious accident involving human health by accidentally ingesting reclaimed water, and (4) there is a scale merit in the construction cost of on-site water recycling systems. An on-site wastewater recycling system larger than 100 m3/d is more economically justifiable when compared to a conventional domestic water supply system. An on-site water recycling system can provide an effective, safe, and economical urban water resource for non-potable water reuse applications.

scholarly journals Reclaiming Suburbia: Differences in Local Identity and Public Perceptions of Potable Water Reuse

2019 ◽  
Vol 11 (3) ◽  
pp. 564 ◽  
Author(s):  
Samantha Redman ◽  
Kerri Jean Ormerod ◽  
Scott Kelley
Keyword(s):  
Urban Areas ◽  
Water Reuse ◽  
Potable Water ◽  
Reclaimed Water ◽  
Public Perceptions ◽  
Western United States ◽  
Treated Wastewater ◽  
Local Identity ◽  
Wastewater Disposal ◽  
Northern Nevada

Urban water managers are increasingly interested in incorporating reclaimed water into drinking supplies, particularly in rapidly growing arid and semi-arid urban areas, such as the western United States. Northern Nevada is one location that is considering augmenting drinking water supplies with reclaimed water, a practice that is known as planned potable water reuse. Potable water reuse can expand water supply and reduce wastewater disposal. However, past studies have shown that the introduction of potable reclaimed water can be controversial and requires an understanding of public perceptions of the resource prior to implementation. This study explores the factors that influence whether or not respondents in northern Nevada express willingness to drink reclaimed water. We pay specific attention to the degree to which self-identification as an urban, suburban, or rural resident influences how people consider using treated wastewater for both potable and non-potable purposes. To address this, we conducted a survey to assess community perceptions of reclaimed water use and applications in northern Nevada in the spring of 2018. We find that years spent living in the home and a respondent being female are negative and significant predictors of being willing to drink reclaimed water, while having heard of reclaimed water before and self-identification as a suburban resident are positive and significant predictors. As the region becomes more developed, particularly in its growing suburbs, it is essential to understand the nature of the interests and concerns regarding water resources and the expanded use of reclaimed water.

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