In a city this populated, you measure twice and interrupt once.

Optimizer™ helped Los Angeles Sanitation Department decision makers avoid millions of dollars in infrastructure costs associated with a new wastewater flow transfer.

The Los Angeles Sanitation Department (LA San) needs to augment reclaimed water supplies to its Terminal Island Water Reclamation Plant during dry weather periods. A plan to transfer 16 million gallons per day of wastewater from the LA County Joint Water Pollution Control Plant via a 3.5-mile dedicated pipeline was considered at a cost of $12 million. LA San undertook an optimization analysis to evaluate the cost and system performance using one of three potential routes augmenting the existing system as an alternative to the dedicated route option.


Los Angeles, California



Wastewater Flow Transfer




  • Capitalize on existing infrastructure
  • Evaluate multiple options to ensure best spend
  • Utilize an optimized decision support process to make informed decisions

“This project demonstrates how innovative optimization modeling technology produces a viable and unbiased solution for a given issue, particularly when the result is a “big ticket” investment that will impact current and future customers.”

Rowena Lau, P.E.
Acting Environmental Engineer

Utilizing LA San’s existing model with the alternative infrastructure options included in the network, Optimizer analyzed the impact of transferring the additional flow via the existing network along with new pipelines, parallel pipelines, increased siphon capacity, and pump station upgrades along the alternative routes. The analysis included unit costs for the pipelines and infrastructure, system performance criteria, and GIS data for geo-physical features of the area.

The optimization demonstrated the 16 million gallon per day flow can be transferred by taking advantage of the available current capacity with minimal upgrades to the existing system, reducing the necessary investment in new infrastructure to about $6 million (50% less). The analysis allowed LA San to rapidly make an informed decision in the selection of the most cost-effective transfer route to meet both design and performance standards.


The LABOS brought in the experts to weigh the pros and cons of four options.
The Bureau retained Optimatics to conduct an optimization analysis with the objective of identifying the best route and facilities to transfer this flow on a constant basis. Using the hydraulic model from an up-to-date, calibrated collection system model for one of the service areas as input, it completed an optimization analysis that helped the Bureau see the benefits and drawbacks of the different routes.