Point-of-use water treatment

Point-of-use (POU) water treatment refers to a variety of different water treatment methods (physical, chemical and biological) used to improve water quality for an intended use (drinking, bathing, washing, irrigation, etc), at the point of consumption instead of at a centralized scale (involving a distribution network). POU treatment encompasses water treatment at a more decentralized scale like in a small community or at the household level; furthermore, safely storing water (especially unclean water) is a huge challenge, therefore upon water use, a POU treatment method (below) can be applied to improve the water quality [1].

Contents

Methods

POU treatment methods include one or a combination of the following treatment methods:

A multi-barrier approach utilizing more than one of these methods is often recommended to maximize the effectiveness in inactivating pathogens that cause diarrheal diseases, removing particulates and/or contaminants that are naturally toxic or inhibit the effectiveness of the desired water treatment method [2][3].

Underdeveloped regions

In underdeveloped regions (underdeveloped nations), water treatment often becomes a challenge and requires alternatives to the conventional water treatment system consisting of coagulation, flocculation, sedimentation, filtration and disinfection (most commonly chlorination).

This conventional system alone demands large amounts of capital investment and complex water management infrastructure that would often not be feasible in decentralized, poor, underdeveloped regions. In this case, point of use treatment systems, technologies and methods allow underdeveloped regions to utilize simpler, more cost effective means of water purification [3].

Example

Communal taps are sometimes found in underdeveloped regions (underdeveloped nations) whereby community members can collect water from a somewhat centralized location (tap, faucet, pump) and treat the water with any of the previously mentioned POU methods. If communal taps are not an option, people typically make daily trips to the nearby water source (river, lake, etc. which can sometimes be miles away), collect water in large jars/containers and transport it home to be treated with one of the previously mentioned POU methods.

Developed regions

In developed regions (developed nations), POU treatment methods are found to supplement water treatment and aid in ensuring potable water or safeguarding against particular contaminants of concern. As water leaves the water treatment plant, water most often meets or exceeds standards regulated by the local governing authority (EPA in the US); however due to a large amount of aging infrastructure (dating back to the 1920s for public utilities in the US and before depending on the age of the home) water quality has the potential to degrade leaving people to find aesthetically unpleasing and sometimes unsafe drinking water at the tap within the household.

Example

Because of aging infrastructure many products have been developed to aid in water treatment at the home like the following:

Recreational application

While camping, people are often advised to add iodine, chlorine tablets or one of a series of other products to cleanse the local surface water before consuming it. This practice has been used for years and is highly recommended to ensure the water is bacteriologically suitable, or as suitable as possible to be consumed. Historically speaking, iodine tablets were used but with newer technologies and products, chlorine tablets have become less expensive and seem to be the preferred treatment.

See also

References

  1. ^ Sobsey, M.D. Managing Water in the Home: Accelerated Health Gains from Improved Water Supply, Geneva, Switzerland: World Health Organization (WHO), 2002.
  2. ^ Home Water Treatment Devices, National Science Foundation (NSF), NSF International, 2004.
  3. ^ a b Point-of-Use (POU) Water Quality, USAID: Environmental Health, 2006.

External links