Standard Article

Wastewater Treatment—Small Scale

Waste Water Treatment

  1. Guenter Langergraber

Published Online: 15 APR 2005

DOI: 10.1002/047147844X.ww319

Water Encyclopedia

Water Encyclopedia

How to Cite

Langergraber, G. 2005. Wastewater Treatment—Small Scale. Water Encyclopedia. 1:840–844.

Author Information

  1. BOKU-University of Natural Resources and Applied Life Sciences, Vienna, Austria

Publication History

  1. Published Online: 15 APR 2005


Small wastewater treatment plants are defined as those to which fewer than 2'000 people are connected or those whose flow is less than 200 m3/d. These are treatment plants for small communities, villages, institutions, hotels, and camping resorts.

There are a tremendous number of small wastewater treatment plants worldwide. Small treatment works are needed mainly in rural areas to treat municipal wastewater. However, technologies to treat wastewater from industry are also important. The separate treatment of wastewater from certain processes provides opportunities to reuse water and to reduce the overall consumption of freshwater.

In rural areas and also in large cities that are not yet provided with sewers, sanitation requirements can be met at a reasonable price and on a reasonable timescale by constructing small but highly compact and efficient plants to serve clusters of dwellings.

Small wastewater treatment plants are required to satisfy very different needs which can be integrated into infrastructures at very different stages of development and sophistication. Engineers are called upon to provide technologies that are reliable, easy to operate and control, and tolerant of variations in the influent. The task is difficult and needs an interdisciplinary approach that takes into account local conditions.


  • small scale;
  • source control;
  • treatment methods;
  • wastewater treatment