Water Reuse Policies for Potable Use
Cecilia Tortajada, Choon Nam Ong, Cecilia Tortajada, Choon Nam Ong
- 178 pages
- English
- ePUB (mobile friendly)
- Available on iOS & Android
Water Reuse Policies for Potable Use
Cecilia Tortajada, Choon Nam Ong, Cecilia Tortajada, Choon Nam Ong
About This Book
As water demand has increased globally and resources have become more limited because of physical scarcity, over-exploitation and pollution, it has been necessary to develop more options for water supplies. These options include the production at large scale of high-quality reused water from municipal sources for potable uses. Their economic, social and environmental benefits have been many as they have addressed supply scarcity, efficient resource use and environmental and public health considerations.
This book includes discussions on potable water reuse history; emerging contaminants and public health; public-private partnerships in the water reuse sector; regulatory frameworks for reused water in the United States and Europe; experiences in Australia, China in general and Beijing in particular, Singapore and Windhoek; narratives and public acceptance and perceptions of alternative water sources.
The main constraints on implementation of water reuse projects in different parts of the world seem to have been lack of full public support due to perceived health hazards and environmental impacts. A main handicap has been that governments and water utilities have been slow to understand public concerns and perceptions. After several backlashes, public information, communication and awareness campaigns, broader participation and educational programmes have become integral parts of development policy and decision-making frameworks.
Frequently asked questions
Information
Potable water reuse history and a new framework for decision making
Joseph A. Cotruvo
Joseph Cotruvo & Associates, LLC, Washington, USA
ABSTRACT
Introduction
- Unplanned or deliberate IPR: Untreated or treated upstream surface water discharge downstream to a municipal drinking water plant.
- Planned IPR with groundwater recharge: Soil aquifer treatment or injection of highly treated water into recoverable aquifers.
- Planned IPR: Advanced treated wastewater with surface discharge to a water body or groundwater recharge.
- IPR/DPR: Advance treated wastewater is discharged to the entry point of a drinking water treatment plant, or post-treatment blending, or storage in surface or groundwater prior to distribution.
- Pipe-to-pipe DPR: Treated wastewater is discharged to drinking water distribution without an environmental but possibly with an engineered storage buffer.
Water technology
- standards to define potable water regardless of source
- comprehensive characterization of source waters
- more toxicology study including concentrate studies
- better treatment technology with improved reliability and redundancy
- more implementation of groundwater recharge
- more non-potable reuse options.
- The state of science and technical understanding in the water industry has made major progress.
- Wastewater management and pretreatment have been instituted and the quality of wastewater has improved.
- Drinking water standards exist for almost 100 contaminants, plus broad treatment requirements for filtration and disinfection, as well as guidelines for hundreds of chemicals.
- Sophisticated instruments and analytical methods now allow quantitation at parts per trillion and lower levels, including more real-time on-line methods.
- Treatment technology now includes biological activated carbon, MF, UF, NF, and RO membranes, and advanced oxidation and ion-exchange resins.
Windhoek, Namibia
- 1969 – FeCl3, coagulation, dissolved air flotation, rapid sand, GAC, Cl2, NaOH, blend (now considered non-potable; irrigation only)
- 1997 – PAC, pre-O3, FeCl3/polymer, coagulation, dissolved air flotation, KMnO4, rapid sand, O3, BAC, GAC, UF, Cl2, NaOH, blend (about 30% recycled water)
NASA – International Space Station
- Urine distillate and air condensate recovery
- Multifiltration, vapour compression distillation, catalytic reactor, ion exchange, iodine
Big Spring, Texas
- Chlorinated secondary effluent, granular media → MF, RO, advanced oxidation, blend → flocculation, sedimentation, granular media, disinfection → distribution (issue: high salinity in natural source)
Singapore NEWater
- Secondary treated wastewater, UF, RO, UV
Orange County, California
- Groundwater replenishment and seawater intrusion barrier, 100 million gallons per day (mgd)
- Secondary effluent, NH2Cl, MF, cartridge filter, RO (three-stage), H2O2/UV advanced oxidation, strip CO2, lime stabilization
Domestic/commercial potable recycling
- Pure Cycle, Colorado, 1976–1982 – household wastewater, grinder, biodisk/cloth filter, MF, IX, UV → household storage tank
- Tangent Company in Ohio is developing and evaluating a single-building DPR system.
Water reuse policy development
Framework for direct potable reuse
- Identifying potential public health risks and appropriate measures for their mitigation
- Defining the elements of a regulatory permitti...