Planning and Implementing Water System Interconnections


  • Jeff Cruickshank PE, Tom Tant PE - Hazen and Sawyer

This presentation reviews lessons learned from recent projects that involved planning and implementing interconnections between finished water systems in North Carolina.

The planning process usually begins with hydraulic modeling, and an overview provides insights from recent interconnection modeling studies. Topics include choosing assumed demand conditions, interpreting predicted pressures, and tracing interconnection impacts back to supply sources. Modeling results will demonstrate the need for extended period simulations to ensure that predicted interconnection flows are sustainable.

A recent implementation project provides real-world lessons about interconnection planning beyond hydraulic modeling.

Testing interconnections after construction is also covered, including comparing observed flows and pressures to model predictions. Examples will show how to investigate discrepancies between model predictions and measurements.

The presentation reviews the process of bringing interconnections on-line during an emergency. Models can predict which tank empties first after a supply failure and calculate how many hours a utility has to start up emergency supplies from interconnections. Developing 1-page standard operating procedures for activating interconnections is critical when the clock starts ticking.

Modeling results show examples of how to maintain water quality in interconnection piping during normal operation, in order to reduce the time required for flushing before activating interconnections.

This presentation will help water utilities understand the importance of interconnections and the planning and implementation process associated with them.

For more information, please contact the author at

Hear about new publications with our email newsletter

We will never share your details with anyone else.


Newsletter Newsletter

Horizons Fall 2017 (pdf)

Horizons showcases significant water, wastewater, reuse, and stormwater projects and innovations that help our clients to achieve their goals, and can help you achieve yours. Articles are written by top engineers and process group leaders, demonstrating and explaining the beneficial application of a variety of technologies and tools.

View previous issues »