Since our first industrial water treatment plant design project in the 1940s, we have been instrumental in more than 1,000 water treatment facility designs, including treatment plant modification, expansion and rehabilitation projects. We have also been involved with many of the largest and most complex water and wastewater treatment plant design projects in the world, resulting in an aggregate world-wide water treatment capacity in excess of 10 billion gallons per day. We have also conducted nearly 100 pilot studies of treatment processes that have been used to cost-effectively meet state and federal regulations. We have unsurpassed experience modeling, planning, designing and optimizing some of the largest and most advanced water treatment facilities in the world.

Anaheim Water Recycling Demonstration Project, City of Anaheim Water Services, California, USA

The City selected MWH to design the Water Recycling Demonstration Facility (WRDF), which will consist of a membrane bioreactor system, ozonation and UV disinfection. The WRDF was built in two phases with an ultimate treatment capacity of 100,000 gpd. Phase 1 of the project consisted of designing and building a 50,000 gpd facility, which included an influent diversion pump station, fine screen, nitrification and de-nitrification tanks, membrane filtration system, ozonation system, UV disinfection system, clear well and supporting facilities like odor control.

Gibson Island Advanced Water Treatment Plant, State of Queensland, Australia

MWH served as lead designer in the alliance that completed the detailed water treatment design and construction of the Gibson Island Advanced Water Treatment Plant (AWTP) in 2008. The plant treats 26 mgd of secondary effluent from the Gibson Island wastewater treatment plant and provides reclaimed water to power stations, industrial users and possibly agricultural users. The treatment process includes tanks; screens; pumping systems; high-rate ballasted clarification for removal of phosphorus; microfiltration; reverse osmosis; advanced oxidation using hydrogen peroxide and UV light; and chemical dosing systems for the main liquid stream.

Regional Recycled Water Supply Augmentation Program, Metropolitan Water District of Southern California and County Sanitation Districts of Los Angeles County, California, USA

Beginning in 2005, MWH, in close collaboration with the Metropolitan Water District (MWD), developed a strategic assessment for large-scale water reuse in the Los Angeles Basin. MWH assessed the potential for augmenting potable supplies with highly purified effluent from the County Sanitation Districts of Los Angeles County. MWH is currently designing a Demonstration Facility at the Joint Water Pollution Control Plant that will focus on proving technologies for approval by regulators. MWH is working closely with an Advisory Panel and with regulators to seek approval of newer technologies.

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IUA Names New Leadership

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MWH Releases New “Water Treatment” Edition

MWH, now part of Stantec has released the third edition of “Water Treatment – Principles and Design,” a comprehensive textbook dedicated to the science and practice of water treatment.

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A Day in the Life of Mariana

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