Earth Tech has used InfoWorks WS from Wallingford Software to develop a record-breaking all-mains model of Miami-Dade’s water supply system in order to achieve an accurate representation of the entire distribution process. The new dynamic model covers the entire 250,000-pipe network, as well as all the associated facilities.
Final calibration will be the next stage of the modeling process. It is believed that Miami-Dade will then have the largest water distribution model in use anywhere in the world – though it will not hold the record for long. InfoWorks WS is also being used to build an even larger model in Shanghai, China, that already has 400,000 pipes but is not yet fully calibrated.
The Miami-Date model includes everything from the smallest 1-inch supply pipes to major treatment works serving Miami-Dade County. The raw water supply is also being added to the model.
Representing something of this scale has meant overcoming a succession of challenges, such as finding out information about pipes laid a century ago. Calibration work and field research is now taking place to fine-tune the model in readiness for its use in a wide range of planning and operational tasks.
Modeling has been carried out in great detail. The task initially appeared daunting: the statistics are impressive. The model encompasses 5,600 miles of pipes, ranging from 1" to 120" in diameter. There are 218,000 nodes and 236,000 pipes in the model, as well as facilities including 49 treated-water pumps, 19 storage facilities and 98 raw-water wells.
The county’s original hydraulic model, built using another software system, was limited both in its coverage and its functionality, said Earth Tech senior hydrotechnical engineer Eppo Eerkes.
“It was only a single step simulation and couldn’t do extended-period modeling,” he said.
Only the trunk system was modeled, which served well for a planning-level analysis, but could not be used for detailed local distribution analysis.
“It also had a simplistic modeling of the pumping and storage facilities,” Eerkes said.
Only the main pressure zone was modeled. In addition to the smaller pipes that were not included, other exclusions were the raw water network and the well system.