本文提供了俄亥俄州托莱多市一家水处理厂的自动化案例研究（重点是化学品处理和加料），并为考虑安装新仪表系统或更新旧系统的其他公用事业公司提供了一份冗长的建议清单。托莱多系统将为托莱多市节省化学、能源和人力开支。在该系统的详细设计和后续建设之前完成的一项研究表明，该系统将在六年内自行支付费用。本文介绍了托莱多的水源、处理机组、处理厂配置和化学控制回路。 详细讨论了在能源和人力方面的节约，以及设计自动化系统的建议清单。

This paper offers a case study of automation in a water treatment plant in Toledo, Ohio (focusing on chemical handling and feeding) and gives a lengthy list of recommendations for other utilities considering installation of a new instrumentation system or the update of an older system. The Toledo system will save the City of Toledo money on chemical, energy, and manpower expenditures. A study completed prior to the detailed design and subsequent construction of the system, showed that the system will pay for itself in six years. This paper describes Toledo's water source, treatment train, treatment plant configuration, and chemical control loops. Detailed discussion on the savings in energy and manpower are given, as well as the list of recommendations on designing an automation system.