根据土地利用数据计算需水量传统上是一个手工过程。这种手工计算耗时、繁琐，而且容易出错。现在，有了低成本的GIS和数据库应用程序，这一过程的大部分都可以实现自动化。自动化带来了几个好处。特别是，它减少了此类计算通常所需的时间，将误差降至最低，并提供了在土地使用边界或配水网络发生变化时快速重新计算需求的能力。本文概述了计算土地使用需求所涉及的过程，解释了该过程是如何实现自动化的，然后简要描述了该过程在几个项目中的应用。

Calculating water demands from land use data has traditionally been a manual process. This manual calculation is time-consuming, tedious, and prone to errors. Now, with the availability of low-cost GIS and database applications, it is possible to automate most of this process. Automation yields several benefits. In particular, it reduces the time generally required for such calculations, minimizes errors, and affords the ability to quickly recalculate demands as land use boundaries or water distribution network changes occur. This paper presents an overview of the process involved in calculating demands from land use, explains how the process has been automated, and then briefly describes how it was applied on several projects.