As a result of population growth, urbanization, and climate change, public water supplies are becoming stressed, and the chances of tapping new water supplies for metropolitan areas are getting more difficult, if not impossible. As a consequence, existing water supplies must go further. One way to achieve this objective is by increased water reuse, particularly in supplementing municipal water supplies. Although water reuse offers many opportunities it also involves a number of problems. A significant cost for nonpotable water reuse in urban areas is associated with the need to provide separate piping and storage systems for reclaimed water. In most situations, the cost of a dual distribution system has been prohibitive and thus, has limited implementation for water reuse programs. The solution to the problem of distribution is to implement direct potable reuse (DPR) of purified water in the existing water distribution system. The purpose of this paper is to consider (a) a future in which DPR will be the norm and (b) the steps that will need to be taken to make this a reality. Following an overview, the rationale for DPR, some examples of DPR projects, technological and implementation issues, and future expectations are examined.
Keywords: direct potable reuse, engineered storage buffer, potable reuse, water reuse
With increasing human populations comes the corresponding increased need for improving water quality in lakes, wastewater ponds, potable water reservoirs, and other water storage facilities. Providing circulation within water reservoirs of all types has long been known to provide meaningful benefits, but the costs to achieve sufficient circulation through diffused aeration or mechanical mixers has been prohibitively high for water bodies with surface areas greater than 1 to 5 acres, or volumes over several...
Background: Nitrification in Alameda Reservoir
The Alameda County Water District (ACWD) operates and maintains the Alameda Reservoir, a 15 MG finished water storage facility located in Fremont, California. The reservoir experienced loss of disinfectant residual as a result of nitrification even during the winter as shown in Figure 1. Nitrification is a biological process in which ammonia-oxidizing bacteria convert free ammonia to nitrite. Year 2002 and 2003 data illustrate the historic difficulty of...
ABSTRACTConsiderable progress has been made over the past 10 years in the assessment and benchmarking of real losses in potable water distribution systems. Most of the advances have been based on the burst and background estimate (BABE) methodology, which was first developed in the mid-1990s by the UK water industry and has since been widely accepted and used in many parts of the world. Since the original BABE methodology was developed, several other key concepts have been added to the evergrowing list of water...
A wave of privatization is rolling through the water industry – at the environment‘s expense? In order to provide an answer to this question, the Environmental-Rating agency oekom research AG, Munich, put a number of water supply companies and manufacturers of water appliances to the environmental test. In results published today, oekom identifies the British water supplier Severn Trent as the environmental leader of the water supply group with a B grade in the overall Environmental-Rating. The Austrian water...
Introduction
Danfoss is a global manufacturer of hermetic compressors, pumps, valves, motors and other electrical control units. The company owns a major manufacturing facility located on a small island, Als, in the Baltic Sea. In 1983 the company was routinely withdrawing two million cubic meters of fresh water from the sole aquifer which supplies the entire island, home to 50,000 residents. This was well within the limit of three million cubic meters authorized by local officials.
In 1983, Danfoss discovered...
Cost-efficient solution for smell emission reduction
The enormous waste quantities that are produced day by day are one of the most difficult problems for the economy as such, for cities and communities and for private households. Storage capacities for waste are scarce everywhere. Therefore solutions of all kinds that reduce waste quantities or recycle waste materials to be reused in the material cycle are top priority for all concerned. For some time now, compost production has been a widely used approach to...
`The oceans are in trouble and so are we,` oceanographer Sylvia Earle, National Geographic explorer in residence and researcher for the Smithsonian, was quoted as saying in an article on the web by Seth Borenstein writing for the Philadelphia Inquirer and San Jose Mercury News Washington Bureaus. Citing a study by the Harvard Medical School`s Center for Health and the Global Environment covering 1976 to 1996, Borenstein reports a greater than fourfold increase in harmful algal blooms (74 to 329). `stranding of...
Abstract
Based on the Cyclical Business and Waste Act, the Used Auto Ordinance (AltautoVO) went into effect on 1st April 1998.
The Used Auto Ordinance regulates in particular the path of the used auto from the last owner to the recycler as well as the requirements placed on the used auto acceptance points and the used auto recycling plants.
This discussion article is concerned with the technical requirements for the used auto recycling plants in compliance with the Annex to the AltautoVO (`Requirements for...
In all, the 1990s have been good for the biosolids recycling community. Greater quantities of biosolids are being beneficially used than ever before, there are national biosolids regulations that are widely accepted as a good baseline, and there is an extensive, accessible network of researchers, practitioners, advisers and public officials who when combined, provide thousands of years worth of valuable knowledge and experience.
We end this decade, however, with perhaps a greater challenge than we started with —...
Hubert Textiles Pty Ltd operates a textile dyeing and printing business. Significant cost savings and environmental benefits have resulted from the installation of a computerised paste mixing system. A payback of approximately 2.5 years was achieved through reduced raw material and waste costs and efficiency improvements.
Background
Hubert Textiles Pty Ltd (Hubert Textiles), trading as Australian Textile Printing Company, is a medium sized family textile printing and dyeing business. The company commenced...
The main advantage of ex situ treatment is that it generally requires shorter time periods, and there is more certainty about the uniformity of treatment because of the ability to monitor and continuously mix the ground water. Ex situ treatment, however, requires pumping of ground water, leading to increased costs and engineering for equipment, possible permitting, and material handling.
Physical/chemical treatment uses the physical properties of the contaminants or the contaminated medium to destroy (i.e,...
Measuring and valuing the health impacts of pollution are very complex and available methods of economic analysis are often rudimentary. In recent years, considerable progress has been made, especially in respect to air pollution. This note summarizes the latest findings and outlines some basic approaches that can be applied in the economic analysis of Bank projects and sector studies. However, a degree of uncertainty still remains, and great care must be taken in their application.
Background
Investments in...
` Appropriate wastewater management, within an overall water resources management program, is essential to responsible use of the environment and to affordable provision of services. Such management programs are best developed at a river basin or sub-catchment level. An approach is outlined for developing a wastewater strategy and an implementation plan for a river basin.`
Integrated Management
The Bank promotes a systematic approach to water resources management, incorporating water resources planning and...
On 12th March 1997, the European Commission adopted a proposal from the Environment Commissioner Ritt Bjerregaard on a European Union strategy to combat acidification. The strategy will, by 2010, reduce significantly the extent of the areas in the European Union where the tolerance of sensitive ecosystems to acidity is exceeded. Main elements of the strategy include establishment of national emission ceilings for each acid rain pollutant; ratification of the UN protocol on further reductions of sulphur emissions;...
It may be necessary to know other subsurface information to remediate inorganics in ground water, surface water, and leachate. Treatability studies are usually necessary to ensure that the contaminated ground water can be treated effectively at the design flow. A subsurface geologic characterization would be particularly important to characterize the effects of adsorption and other processes of attenuation. Ground water models are also often needed to predict flow characteristics, changes in contaminant mixes and...
Introduction Sustainability or `sustainable development` has become a term which is frequently applied to land use and social planning and resource issues. Sustainability is a concept which draws attention to development practices which can degrade natural ecosystems and deplete natural resources. If development is defined broadly to include any cultural activity, then sustainable development may be defined as any practice that meets the needs of the present population without compromising the ability of future...
Pressures on the environment may occur through chemical, physical and biological agents. The subject of this study is physical agents, where physical fields are examined.
Physical fields are part of the natural environment. Depending upon their properties and the surrounding conditions, physical fields are transmitted through the spaces in which we live, potentially affecting human health and nature. Human activity can add to, modify, and enhance and reduce the intensity of these fields. Furthermore, changes in...
Abstract
This paper describes two successful applications of ultrafiltration (UF) and reverse osmosis (RO) membrane technology used to reclaim water, reduce waste water discharge costs. The first case history covers oily waste water treatment at a major aluminum beverage can manufacturing plant. The second case describes treatment of waste water from a multi-plating bath section of a major wheelchair manufacturing facility. The mechanisms of separation effected by both UF and RO are described at the molecular...
Introduction
The notion that salt could be removed from seawater without a phase change took hold of Dr. Sourirajan`s imagination in the late 1950`s. The actual invention of the reverse osmosis (RO) membrane took place in his laboratory at UCLA around 1960. (Thus Sourirajan could be called not only the `Father of Reverse Osmosis,` but the initiator of all crossflow membrane technology.) The full commercialization of RO and its sister crossflow technology, ultrafiltration (UF), occurred in the early 1970`s. About...
Abstract
As water and sewer costs are expected to increase over the next decade, membrane technology will continue to be a viable and economical option in the recovery and reuse of water. This paper describes the mechanism of membrane effected separation (specifically reverse osmosis, ultrafiltration and microfiltration), membranes commercially available, membrane element configurations, and how complete membrane systems are designed. The paper also discusses case histories of a variety of proven applications,...
This article is excerpted from `Pure Water Handbook` published by Osmonics®, Inc. of Minnetonka, Minnesota USA and is printed with permission of Osmonics, Inc.
Water treatment can be defined as any procedure or method used to alter the chemical composition or natural `behavior` of a water supply. Water supplies are classified as either surface water or groundwater. The majority of public or municipal water comes from surface water such as rivers, lakes, and reservoirs. The majority of private water supplies...
Better than 95% of all dialysis centers use water purification equipment to purify water for dialysis. The centerpiece of these water purification systems has become reverse osmosis. In conjunction with sound pretreatment, RO has proven itself to be the safest, most reliable, and most economical method of purifying water for dialysis.
Water plays an important, life-sustaining role for dialysis patients. And as such, the water used for this critical function must be of special quality.
When hemodialysis started...
Customer comments
No comments were found for Direct potable reuse: a future imperative. Be the first to comment!
