利用地理信息开发管道评估计划的关键组成部分 系统（GIS）工具是使用准确和完整的数据。然而，由于种种原因， 这些数据可能缺失或不完整。丢失大量数据可能会导致 严重妨碍（或对）病情评估过程。 在管道GIS数据库（地理数据库）中包含的所有管道特征中，年龄， 直径和材料是最重要的。本文讨论了该方法及其应用 用于解释大城市供水系统中这些缺失数据的假设 系统以进行管道状况评估、预测趋势、估算经济效益 制定再投资预算，优先考虑管道更换或修复项目。 管道状况评估的一个主要组成部分是对历史主破裂的评估 记录。这些记录通常与GIS管道数据和相关性分开保存 将中断数据转换为管道数据是另一个挑战。空间定位主断裂修复 由于主破裂修复地址或维修计划中可能存在错误，管道库存有限制 其他不可预见的情况。本文还介绍了GIS技术和质量控制 用于开发高置信度主断裂数据库的检查，并提供 准确描述现有系统的状况。包括表格，数字。

A key component for developing a pipeline assessment program using Geographic Information System (GIS) tools is the use of accurate and complete data. However, for a variety of reasons, these data may be missing or incomplete. Having a large percentage of missing data can significantly hamper (or pose a significant challenge to) the condition assessment process. Among all pipeline characteristics included in a pipeline GIS database (geodatabase), age, diameter, and material are the most important. This paper discusses the approach and assumptions used to account for these missing data for a large metropolitan water distribution system in order to conduct a pipeline condition assessment, predict trends, estimate economic lives, develop a reinvestment budget and prioritize pipeline replacement or rehabilitation projects. A primary component of pipeline condition assessments is the evaluation of historical main break records. These records are often maintained separately from the GIS pipeline data and correlation of the break data to pipeline data presents another challenge. Spatially locating main break repairs to a pipeline inventory has limitations due to possible errors in the main break repair address or other unforeseen circumstances. This paper also presents GIS techniques and quality control checks that were used to develop a database of high confidence main breaks and provide an accurate characterization of the condition of the existing system. Includes table, figures.