The idea at the core of the research reported in the present paper is the use of indigenous halophilic consortia of an oilfield for treatment of the produced water (PW) generated in the same oilfield. To test this idea water and soil-based microbial sources obtained from desalination units of two oilfields were enriched in PW obtained from the same oilfield and supplemented with either yeast extract (YE) or Mueller-Hinton medium containing crude oil. Enriched soil-based microbial consortia (termed EVPS) gave a meaningfully higher maximum achievable biomass concentration, and amount of COD removed when grown on PW supplemented with YE compared to enriched water based ones. The supplementation of PW with inorganic nitrogen and phosphorous sources resulted in around 35% COD removal whereas supplementation with YE increased the PW COD removal to 62%. Microbial analysis of EVPS with Illumina HiSeq/MiSeq showed that bacteria had higher richness and diversity than archaea. The dominant bacteria genera were Chromohalobacter, Idiomarina, and Marinobacter, whereas Haloterrigena, Haloferax, and Methanohalophilus were the dominant genera amongst the archaea. Based on previous reports, the identified genera in EVPS have a wide salt tolerance range and are collectively capable of biodegrading most of the organic compounds prevalent in PW. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.