Distribution Systems Research

Throughout the world, millions of miles of water distribution pipeline provide drinking water for individual and industry use. Some of these water distribution systems have been in service for more than 100 years. Our water delivery systems need attention, and EPA's research supports clean drinking water solutions in some of the most interesting areas of study:

• Corrosion
• Distribution System Simulators
• Leak Detection
• EPANET
• Environmental Technology Verification
• Aging Water Infrastructure

Water distribution systems are large networks of storage tanks, valves, pumps, and pipes that transport finished water to consumers. (Finished water is that which has gone through all the processes in a water treatment plant and is ready for delivery.) Because of their design, water distribution systems include areas of vulnerability where contamination can occur. Corrosion of our water pipelines is a key area of research. In water distribution pipelines, valves, and fixtures, corrosion can cause the degradation of our drinking water quality. Through the Drinking Water Distribution Systems Corrosion Research Program, EPA is gaining a better understanding of corrosion and its related reactions so that clean, fresh drinking water is delivered to you every time.

DSS‑1 and DSS‑2 are two water distribution system simulators used to evaluate and understand the dynamics that influence water quality within distribution pipelines. Both DSS units replicate water flow conditions and are located above ground to provide easy access to the entire pipe network. That way, scientists can study the physical, chemical, and biological activities that occur within pipelines.

As water travels through distribution systems, it comes into contact with a wide range of materials, some of which can cause significant changes to the quality of the finished water supply. For example, solids can settle out during low‑flow conditions and can be suspended during high flow. Also, disinfection agents and water additives react with organic and inorganic materials to generate by‑products that may be unwelcome in a community’s water supply. Then there’s biofilm.

Biofilm is a complex microenvironment that is created when oxidant‑resistant microorganisms colonize on pipe surfaces. The trouble with biofilm is that it is highly resistant to many disinfection methods and techniques. That’s where DSS‑1 and DSS‑2 come in. At EPA’s Test and Evaluation Facility in Cincinnati, Ohio, scientists are using DSS‑1 and DSS‑2 to study factors that influence biofilm growth and what can be done to control it.

To aid in its research activities, EPA uses Windows-based software called EPANET to model water distribution piping systems. EPANET performs extended‑period simulation of the hydraulic and water quality behavior within pressurized pipe networks.

Some of EPA’s research is done on water long before it ever reaches the pipes that transport it. For example, research has shown that as water moves through the natural hydrologic cycle, it develops characteristic isotopic labels (called fingerprints) so that water in one environment can be distinguished from water in other environments. This emerging technology, called isotope hydrology, uses nuclear techniques to study the events and processes in the hydrologic cycle.

Technical Contact:

Darren Lytle (513) 569‑7432

See Also:

Corrosion, Scaling, and Metal Mobility Research

Distribution System Simulators

Test and Evaluation Facility

Leak Detection

Urban Watershed Research Facility

EPANET

Multi‑Parameter Water Monitors for Distribution Systems

Reverse Osmosis-Based Point-of-Use Devices for Microbiological Agents

Reverse Osmosis-Based Point-of-Use Devices for Chemical Agents

Cross-Connection and Backflow Vulnerability: Monitoring and Detection

Environmental Technology Verification (ETV)