However, implementation of large and centralised drinking water treatments in developing countries is highly unlikely due to investments, civil construction, maintenance of infrastructures and availability of chemicals that are required. As a consequence, people in many developing countries are forced to consume water directly from natural sources or apply household water treatments as chlorination, solar disinfection or boiling, that have low cost but variable effectiveness.
Centralised water treatment and a piped distribution network have had a mixed history primarily due to high initial costs and operation and maintenance, inadequate access to training, management and finance sufficient to support a fairly complex system for the long term. These complete systems are also slow to be implemented so waterborne disease continues in the interim.
==Costs==
* J.M. Arnalà , B. Garcia-Fayos, G. Verdu, J. Lora. [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CHcQFjAG&url=http%3A%2F%2Fwww.desline.com%2Farticoli%2F10560.pdf&ei=c5W1T8niOYigiAKU-t33Bg&usg=AFQjCNGmnmVfvj7uDFea7mdbzxWgssH3IA&sig2=gzJRkqbTVhlAT6e8xZUzEA Ultrafiltration as an alternative membrane technology to obtain safe drinking water from surface water: 10 years of experience on the scope of the AQUAPOT project.] Polytechnic University of Valencia, Chemical and Nuclear Engineering Department, Camino de Vera s/n 46022 Valencia, Spain. May 2008.
* [http://www.epa.gov/p3/success/berkeley.html Shedding Light on Clean Drinking Water.] EPA.
*[http://www.ncbi.nlm.nih.gov/pubmed/11225283 Safe drinking water production in rural areas: a comparison between developed and less developed countries.]
