recycled water

New On-Site Water Generation Policy Brief

California faces growing water scarcity concerns. Droughts pose continuous uncertainties to the water supply, but on-site water recycling could help alleviate the pressures of these uncertainties. On-site water recycling could contribute to increased water supply reliability as well as other environmental goals, such as reduced greenhouse gas emissions.

On-site water recycling systems are primarily one of two technology types - constructed wetlands or membrane bioreactors (MBR). For more information on these technologies, please refer to the Alliance’s report, “On-Site Water Generation: An Analysis of Options and Case Study” published December 2012.

The 2012 Alliance study found that on-site recycled water systems can supply water at lower energy intensity than imported water and desalination in Southern California. Nevertheless, most of the existing applications of recycled water are municipal-level wastewater treatment plants. On-site water recycling systems draw wastewater directly from a building’s toilets, showers, and laundry, treat it on-site, and reuse it to meet on-site non-potable needs, such as toilet flushing and irrigation. Installing these systems requires developers to not only manage the initial capital cost, but to confront a challenging regulatory environment. On-site water recycling is a relatively new concept and doesn’t fit neatly into existing regulatory frameworks focused on water-recycling and water- and waste-water treatment. Figuring out how to apply existing regulations – and understanding if the existing frameworks even apply – can be challenging for project developers as well as for those charged with preserving public health and safety. New regulatory frameworks must be developed to enable the installation of these systems.

As a follow-up to the 2012 Alliance Huntington Beach Study, the Alliance investigated further to verify the list of key regulatory hurdles for on-site water recycling and to identify potential solutions. A game-changer like revising the regulatory framework may take considerable time and resources, but the Alliance aims to also present good first steps. These are meant to be easier to implement in the short-term to generate momentum for those goals that are harder to achieve.

To first create awareness regarding the regulatory hurdles facing on-site water recycling system installations, the Alliance has released a new study entitled California On-Site Water Recycling: Policy Brief. This study documents the barriers to on-site water recycling systems and also and presents potential solutions. The policy brief focuses on the following barriers:

  • Lack of clear information about how to apply for permits;
  • Expensive daily coliform laboratory sampling and analysis
  • Stringent certification requirements for system operators

 

Key study conclusions include:

·      On-site recycled water systems are an emerging technology with the potential to play a role in helping manage California’s increasing water scarcity. 

·      Immediate actions should be taken to perform additional work on understanding potential regulatory models, estimating benefits, and initiating pilot activity.

·      An information portal should be designed so that potential developers of on-site water recycling systems and staff at key agencies have access to detailed information. 

·      One stretch goal to work towards is an exception to the Title 22 requirement for daily coliform sampling for on-site water recycling systems with a track-record of high water quality.

The study also highlights a number of case studies as examples of on-site water recycling. Download  the full report for more details.

 

New On-Site Water Generation Study

 

California water supplies are stressed as a result of decreasing supply and increasing demand.  While conservation and efficiency are the most cost-effective solutions, they may not completely solve the problem. Consequently, California water planners are considering multiple alternate water supply options including:

  • Desalination
  • Brackish water treatment
  • Rainwater harvesting (storm water capture)
  • Recycled water

Of these, water recycling is the only option that is applicable across the entire state and which can produce a relatively consistent resource regardless of the season or weather.  Wherever there is a wastewater treatment plant there is an opportunity to generate a local supply of recycled water.

Indeed, generating recycled water is not a challenge, distributing it is.  A major barrier to implementing a successful regional recycled water system is the cost of distribution pipelines. Typically a network of distribution pipelines and pump stations is needed to connect existing municipal water reclamation plants to potential recycled water customers.  Constructing these distribution systems can be expensive ($2-4 million per mile), especially in heavily developed areas such as Southern California. As a result, excess recycled water supply generated by large centralized plants cannot always be used cost-effectively. The Alliance’s 2008 report on recycled water shows that enough existing recycled water supply to meet all of Southern California’s projected increase in water use through 2030 is currently being released to streams and the ocean without benefit.

Recycled water can be implemented on a smaller scale; generating water in the same location as its demand eliminates the need for expensive distribution systems. Additionally, water supply and conveyance accounts for the majority of energy use by the state’s water infrastructure - imported water is among the most energy intensive (especially in Southern California).  On-site water generation has the potential to not only conserve water also save embedded energy in water.

To better understand the opportunity for on-site water generation, the Alliance has released a new study entitled On-Site Water Generation: An Analysis of Options and Case Study The study documents the characteristics of on-site water generation systems and also conducts a detailed cost benefit analysis for a representative case study on the City of Huntington Beach, California.Specifically the studyexplores:

  • Types of technologies available to provide on-site water generation
  • Costs and benefit analysis of the on-site water generation options
  • Primary market barriers to technology adoption.

Key study conclusions include:

  • On-site recycled water systems can supply water at lower energy intensity than imported water and desalination in Southern California. 
  • On-site Recycled water systems are most cost-effective in larger capacities. 
  • On-site water recycling relies on a consistent supply of wastewater and thus can provide more water than rainwater harvesting in Southern California

The study also discusses a number of recommendations for California policy-makers to stimulate the production and use of on-site water generation. Download  the full report for more details.

Employing Public Engagement for the Successful Water Reuse Project

Water reuse projects have garnered concern and even opposition from community members and the public. While based on legitimate concerns, public aversion to recycled water is often fueled by a lack of knowledge resulting in an inflated perception of risk. However, active public outreach and participation can effectively shift public opinion. The EPA’s recently released 2012 Guidelines for Water Reuse dedicates an entire chapter to the issue of public outreach. The report (specifically Chapter 8) draws conclusions and recommendations from recent studies on public perception of recycled water and steps towards effective engagement. This post summarizes some of those key findings.

The last decade has seen an increase in public dialogue and increased knowledge about water reuse. A corresponding shift in public opinion was shown in a study conducted by San Diego County Water Authority. Conducted in 2004 and 2011, the study found people who “strongly oppose” recycled water dropped from 45% to 11% while those who “strongly favor” it increased from 12% to 34%.

Public engagement should be framed as a collaborative problem-solving effort that focuses on the benefits of a water reuse program. When the public understands the problem at hand (e.g. water scarcity and drought) and the benefits of implementing recycled water, they can better perceive an improvement in the state of affairs. Public participation should begin with an understanding of why recycled water is needed, the available options for reuse, and the potential concerns.

When presenting information on water reuse, a balance between technical detail and easily understood information is important. This creates validity while effectively relaying information. In the same way, the terminology used to present reuse projects can greatly impact the public’s reception. Some of the terms used in the industry are often not well understood or well received by the general public. The EPA Guidelines show that terms such as “Water that is purer than drinking water” or “Very pure water” were reassuring to over 60% of respondents while less than 20% found “NEWater,” “Recycled water,” and “Reclaimed water” reassuring. Based on their findings, the EPA offers recommendations for public outreach terminology and methods. These include:

  • Emphasis on the purity of recycled water
  • Focus on future uses rather than the source by avoiding the prefix “re”
  • Offer analogies and water reuse in the context of the water cycle
  • Make understanding accessible and avoid technical terms

Public involvement generally begins with direct stakeholder engagement, particularly those who will be most impacted. This can involve activities such as surveys, community events, public meetings, presentations, and workshops. While direct contact and activity is important with key stakeholders, media outreach can play a significant role in shaping the general public perception and increase the flow of information and dialogue among constituencies.

Several water agencies serve as prime examples of successful public engagement and implementation of recycled water projects. Orange County Water District (OCWD) was particularly successful in engaging the public through its diversity of outreach for its Groundwater Replenishment System. OCWD also overcame reuse misconception to garner public support for an indirect potable reuse project. Read more about their success here. San Diego County Water Authority facilitates successful public communication by conducting surveys to measure knowledge and opinions of water issues and then sharing the results with the public.

For more details and advice on successful public engagement, check out Chapter 8 of the EPA’s 2012 Guidelines for Water Reuse.

New Water-Energy Study, Tool, and Web Content

The California Sustainability Alliance (Alliance) has released new water-energy content to assist water agencies in improving the energy efficiency of their infrastructure.  These include the Eastern Municipal Water District: A Case Study of Best-In-Class Water-Energy Programs and Practices report, a Water/Wastewater Agency Energy Analysis and Best Practices Tool, and new website content on selected best practice and emerging technologies for the water industry.

The Eastern Municipal Water District: A Case Study of Best-In-Class Water-Energy Programs and Practices report documents the range of potential energy efficiency and generation opportunities, types of programs and technologies available to help water agencies achieve energy benefits, and the barriers that need to be overcome to increase adoption these practices and technologies.  The Eastern Municipal Water District serves as a case study to illustrate the types of strategies and measures California water agencies can implement to improve energy efficiency.  The report identifies seven key strategies and 27 illustrative measures and emerging technologies.  Some of these measures can reduce energy use and cost by up to 40% with a payback of 2-4 years or increase biogas production by 10-40%. 

As part of this best practices study, the Alliance developed the Water/Wastewater Agency Energy Analysis and Best Practices Tool. The can be used by water agencies to quantify, at a high level, the annual energy costs associated with various sub-systems within a water agency's infrastructure.  Based upon this analysis the tool provides a custom list of best practices and energy savings measures that should be explored to reduce energy use and costs.  The tool is meant to screen and initially prioritize future energy management projects and facilitate discussions within the water agency and between the water agency and its energy utilities.

To supplement the study and the tool, the Alliance added new web-content to document several promising existing best practice strategies and emerging technologies that could reduce energy use in the retail water sector.  These measures include:

These new resources can help water agencies and energy utilities improve the efficiency of California’s water systems.