​​We offer consulting services in water quality, and water treatment and distribution

We have worked with most treatment processes and disinfectants. The projects listed below provided treatment strategies with the overall goal of offering multiple barriers against contaminants. These studies included the conventional treatment processes and various filtration systems, as well as biological treatment, activated carbon, membranes, and ion exchange resins. Other projects have addressed the removal of specific contaminants
​(e.g., manganese, volatile organic chemicals, bromide), microorganism inactivation using various disinfectants (chlorine, monochloramine, chlorine dioxide, ozone and UV), and disinfection by-products (DBPs).

Our projects have focused on water quality in distribution systems and customer premise plumbing, but also included system operation and conveyance of untreated water. Many of these studies have addressed disinfectant stability, DBP formation and decay, microbial growth, nitrification, corrosion, metal release and blending of water from various sources (including recycled water). 

Review of Selected Sections of the Guideline for Canadian Drinking Water Quality; for Health Canada

Review of the ammonia section of the Canadian Guideline. This section includes a general description of ammonia sources in a drinking water system, analytical methods, the different types of ammonia treatment methods, and factors that affect their removal capacity and efficiency.

Preparation or Review of the Initial Distribution System Evaluation (IDSE) Plans and Reports; for the City of Buena Park, City of Pasadena Water and Power, City of Glendale, Palmdale Water District, City of Orange, City of Upland, City of Santa Barbara, and City of Tracy, California; and Punta Gorda, Florida
The IDSE was one of the first steps that were required to comply with the Stage 2 Disinfectants and Disinfection By-Products Rule (Stage 2 DBPR) published in 2006. The purpose of the IDSE was to identify locations in the drinking water distribution system where high DBP concentrations would be encountered. A number of approaches were used to prepare the IDSE Plans for the above listed clients.

In addition to the projects listed below, we have assisted water providers respond to citations received from California’s State Water Resources Control Board, and have provided instructors for the Drinking Water Regulations Workshop of the California-Nevada Section of the American Water Works Association (AWWA). 

Assessment of Nitrification in the Potable Water System; for the Las Virgenes Municipal Water District, California

Provide an overall assessment of the nitrification problem in the District’s distribution system. The project aimed at using information that was currently available at the District to assess the severity of the nitrification problem in the distribution system, identify potential causes, and review the District’s monitoring program and Nitrification Control Monitoring Plan.

Corrosion Control Study – Desktop Study; for the City of Torrance, California

Assess the corrosiveness and aggressiveness of the City’s water sources with regards to distribution system piping materials, examine lead and copper data and customer complaints, and identify the most suitable corrosion control strategies to limit water corrosiveness and metal release.

Microbial Occurrences in the Tunnel Conveyance System; for the San Antonio Water Company, California
Identify the source(s) and cause(s) of the total coliform positive samples observed in the Tunnel conveyance system by analyzing water quality data, conducting special samplings, and developing a hydraulic model of the conveyance system to assess water levels and residence times under different flow conditions.

Nitrification Control Study; for the Mesa Water District, California
Assess the extent and causes of nitrification in the distribution system and storage reservoirs. Develop a dynamic plan to control nitrification, preserve disinfectant stability, and limit microbial growth in the distribution system.

La Sierra Pipeline Project – Blending Study; for the Western Municipal Water District, California
Examine disinfectant stability and corrosion/aggressiveness of the potable water following the implementation of chloramination and addition of a new water source.

Blending Requirements for Water from Direct Potable Reuse Treatment Facilities (Project 4536); funded by the Water Research Foundation
Provide recommendations and guidance for the appropriate use of blending as part of a direct potable reuse (DPR) project, including evaluations of treatment, impact of different water qualities and blending locations, effect of corrosion, and the impact of Engineered Storage Buffer design.

Corrosion Control Study Report, Nitrification Monitoring and Action Plan, and Blending of Free Chlorinated and Chloraminated Water; City of Sierra Madre
Assist the City in its efforts to eliminate the corrosion and red/yellow water problems in the distribution system, and prepare a Corrosion Control Study Report. Provide guidance to control nitrification in the distribution system and storage reservoirs, and develop a Nitrification Monitoring and Control Plan. Determine options available to the City to start using its own water sources again without compromise distribution system water quality.

Water Distribution System Water Quality Analysis, Nitrification Occurrences, and Corrosion Control; for the Collier County, Florida
Address nitrification and recurring losses of disinfectant residual in the distribution system by reviewing water treatment strategies, distribution system operation and water quality; evaluate the occurrence of nitrification in the distribution systems, and develop nitrification prevention and monitoring programs. Conduct bench-scale tests of chloramine decay, examine potential occurrences of cross connections, and develop flushing procedures. Examine the corrosiveness/aggressiveness of the water supplies and current corrosion control practices, and conduct pilot tests to identify alternative corrosion inhibitors.

Conveyance and Disinfection System Project; for the Otay Water District, California
Use the available literature to evaluate the potential water quality effects of blending conditioned desalinated seawater with existing water supplies on water distribution facilities, including water quality, disinfectant residual and stability, DBPs, corrosion, biostability and bioregrowth.

Start-up Assistance of the Surface Water Treatment Facility; for the City of Lodi, California
Evaluate the impact of blending treated surface water with local groundwater on distribution system piping, assess the corrosion potential of both types of water and a selection of their blends, and develop a plan to control corrosion in the distribution system.

System-wide Corrosion Control Study; for the Lee County Utilities, Florida
Participate in the preparation of a comprehensive corrosion control study, which included examining the effectiveness of a number of corrosion control strategies, and preparation of conceptual-level cost estimates for the recommended capital improvement projects.

Effect of Nitrification on Corrosion in the Distribution System (Project 4015); funded by Water Research Foundation & U.S. Environmental Protection Agency
Identify the role and significance of nitrification-induced changes to water quality that may affect corrosion in the distribution system, including lead and copper release.

Investigation of Brown Water Complaints in the Drinking Water Distribution System; for the Eastern Municipal Water District, California
Determine the origin and causes of recurring brown water occurrences observed in the distribution system, with accumulations of sediments and deposits. Propose alternatives to resolve these problems.

Evaluation of Water Mixing in Three Reservoirs Located in Santa Clarita Water Division, California, Using Impellers Developed by PAX Scientific, Inc.
Conduct full-scale testing of the effectiveness of the PAX mixers in three drinking water reservoirs.




​AQUAlity Engineering, Inc.

Control of Manganese in Well No. 9; for the City of Torrance, California

Prepare the necessary documents to obtain a waiver from the State for exceedance of the secondary maximum contaminant level for manganese, including an engineering report and a customer survey.

Rarotonga Treatment and Distribution System Recommendations; for the Rarotonga Island, Cook Islands
Recommend water treatment unit processes (which included packaged membrane treatment systems and adequate disinfection), distribution system infrastructure, operations strategies, and a water quality monitoring program to maintain drinking water quality in the water supply system.

Disinfection By-Product Improvements; for the City of Ashland, Oregon
Identify water treatment process changes that could readily be implemented to control DBP formation, which included simulated distribution system (SDS) tests to evaluate three coagulants, various chlorination protocol, and pH adjustment.

Bulk Water Disinfection Targets Study; for the SEQWater, Queensland, Australia
Propose goals, needs, and disinfection target values for the water delivery system of the South East Queensland Water Grid (SEQWater).

Monk Hill Perchlorate and Volatile Organic Compounds Treatment System; for the City of Pasadena Water and Power, California
Provide technical support for the removal of perchlorate and volatile organic chemicals (VOC) from four wells, and engineering services for the chloramination system.

An Electrochemical Reactor to Minimize Brominated DBPs: Impact on Coagulation and Ozonation (Project 3182); funded by the Water Research Foundation
Advance the design and understanding of a previously tested electrolytic reactor used to remove bromide and DBPs, and examine potential synergies with other drinking water treatment processes.

Advanced Water Treatment of Estuarine Water Supplies for Improving Water Quality (Project 3004); funded by the U.S. Environmental Protection Agency and the Water Research Foundation
Fill the knowledge gaps with respect to treatment of estuarine water supplies using existing and advanced technologies (granular activated carbon, powder activated carbon, MIEX® resin, and membranes), and disinfectant combinations (chlorine, chloramines, chlorine dioxide, ozone, and UV).

Optimizing Chloramine Treatment (Project 2760); funded by the Water Research Foundation
Synthesize all relevant research, operation and practical information regarding the use of monochloramine in water treatment, and develop utility case studies.