由于快速增长和有限的供水， 美国各地的许多供水系统 尤其是那些在西方国家的人，意识到 节约用水的必要性。供应二次能源 水是一种减少饮用水需求的方法 水和水允许更多的连接。然而 未计量的二次用水导致 总体用水量增加。二级市场的监管 水将为公用事业提供更多的控制 并将允许居民 用户积极节约户外用水 目的。 作者们探讨了目前的做法，即 供应商正在使用，包括过滤和创新 水表设计，以节约宝贵的水资源。 他们的经验表明，这不仅是次要的 衡量未来的必要性，也是当前的可能性。 供水商可以利用这些信息来学习 借鉴其他系统的经验，规划 他们自己的分销系统的未来。包括24个参考文献、图表。

With rapid growth and limited water supplies, many water systems throughout the United States, in particular those in western states, are aware of the need for water conservation. Supplying secondary water is an approach that reduces demand on potable water and allows for more connections. However, unmetered secondary water use has resulted in an increase in overall water use. The regulation of secondary water would provide utilities increased control of water supplies and would allow residential users to actively conserve water used for outdoor purposes. The authors explore current practices that water suppliers are using, including filtration and innovative meter designs, to conserve precious water resources. Their experiences show that not only is secondary metering a future necessity, it is also a current possibility. Water suppliers can use this information to learn from the experiences of other systems and plan the future of their own distribution systems. Includes 24 references, figures.