Water and Sanitary Sewer Systems Modeling

What is Water Modeling?

Water modeling is a computer program that performs necessary calculations that helps engineers design and analyze complex pressurized piping systems.

This program is also useful in:

• Performing steady-state analyses of water distribution systems with pumps, tanks and controls.
• Performing extended period simulations to analyze the piping systems response to varying supply and demand schedules.
• Performing water quality simulations to determine the water source and age, or track the growth or decay of a chemical constituent throughout the network.
• Performing Fire Flow Analyses on the water systems to determine how a system will behave under extreme conditions and if adequate fire flow protection can be supplied.

The city of Savannah currently owns, operates, and maintains approximately 42 well sites in the Savannah area that is divided into seven distribution systems. These distribution systems consist of over 800 miles of water mains ranging in size from 2" to 30", 16,000 water valves, and 4,000 fire hydrants.

What is Sewer Modeling?

Sewer Modeling is a computer program that designs and analyzes the gravity flow and pressure flow through sanitary sewer pipe networks and lift stations.

This program is also useful in:

• Designing new lift stations
• Analyzing different “what-if” scenarios
• Calculating flows for future development and the effects downstream of that development

The city of Savannah currently owns, operates and maintains approximately 165 lift stations that discharge to four Water Quality Control Plants. These collection systems consist of over 700 miles of sanitary sewer lines ranging in size from 6" to 60", 100 miles of force mains ranging in size from 4" to 30" and 20,000 sanitary sewer manholes.

Water and Sewer Planning and Engineering models water and sewer systems to ensure available hydraulic capacity for existing and future growth. This department uses the latest in technology for modeling the existing and proposed water and sewer systems in the city of Savannah.

Since 1999, the Water and Sewer Planning and Engineering Department has been maintaining the water and sewer modeling for the city of Savannah. These programs are updated when new projects are completed. Approximately 620,000 LF of sanitary sewer lines have been added to the sanitary sewer modeling program and approximately 107,000 LF of water lines have been added to the water modeling program.

In 2003, the Water and Sewer Planning and Engineering Department purchased a new water and sewer modeling program that integrated the water and sewer modeling program with the city's GIS (Geographical Information System) program, allowing more flexibility and the ease of data exchange between the programs.