Search for "Effluent" on Wikipedia, Wikimedia Commons, Wiktionary, Wikiquote, Wikibooks, Wikia, Wikitravel, Google (excludes "Wikipedia", adds "water"), Yahoo (excludes "Wikipedia", adds "water"). In a generic sense, effluent is water which is flowing out of a body of water or a structure, but, generally, effluent is treated sewage which is produced by a sewage treatment plant. Effluent is usually released into a body of water where, hopefully, natural biological processes will work on the impurities in it and restore its purity. However, some water users, such as the Orange County Water District have created facilities for the reuse of water which purify their municipal wastewater.