Managing Disinfectant Residuals in Water Distribution Systems


Maintain minimum residual levels in the distribution system to meet regulatory compliance


Distribution system water quality is a primary factor in balancing regulatory compliance and customer satisfaction. Operators must carefully regulate disinfectant residual in drinking water while reducing the potential for disinfection byproduct formation. Traditional operational procedures to manage disinfectant levels in the distribution network are costly and time consuming. Monoclor® RCS chloramine management system is an intelligent, automated disinfectant boosting system that gives operators the ability to set, control and cost-effectively maintain residual levels in water storage tanks and key locations in the distribution system.

What is the chlorine limit in drinking water?

Drinking water distributed by SUEZ meets or exceeds all federal requirements. The U.S. Environmental Protection Agency sets the National Primary Drinking Water Regulations (NPDWR), legally enforceable primary standards and treatment techniques. The aim of these regulations is to protect public health by limiting the levels of contaminants in drinking water. The NPDWR include levels for chlorine, chloramine and other disinfectants.

Chloramines, also known as secondary disinfection, are commonly formed when ammonia is added to chlorine to treat drinking water. They generally provide longer-lasting disinfection as the water moves through distribution pipes to the tap. The US EPA has set Maximum Residual Disinfection Level Goals (MRDLG)—that is, the level of a drinking water disinfectant below which there is no known or expected health risk—for chlorine and chloramine. For both disinfectants, the federal MRDLG is 4 parts per million
The Monoclor® RCS chloramine residual management system
Monoclor® RCS chloramine management system performs four discrete functions at the storage tank level to proactively control disinfectant levels in drinking water, preventing nitrification and coliform hits.


Powerful tank-mixing technology ensures homogeneous tank chemistry, so that tanks do not become stratified and disinfectant levels remain consistent throughout the tank.

Monitoring safe chlorine levels in drinking water

The Monoclor® RCS chloramine management system analyzes changing tank conditions. Then an automated chemical feed system and an advanced control algorithm maintain residual levels.

Controlling chloramine disinfection levels needed

A sophisticated control algorithm responds to changing levels in real time, employing real-time data to automatically calculate the dosing of chemical reagents needed.

Dosing chemicals for precise treatment

The system tracks changes in tank water quality, relying on a process control feedback loop with reliable chemical dosing skids to achieve precise levels.

Value of active water mixers

  • MAINTAIN quality of drinking water
  • SIMPLIFY control
  • REDUCE costs