气候变化对城市供水管网系统的脆弱性影响评价及其适应策略研究

Climate change and rapid urbanization will together have strong impacts on the fragile urban water resource systems. The lifespan of urban water distribution systems ranges from serveral decades to more than 100 years, which is equivalent to the time scale of climate change effects. However, the conventional approach to planning and designing urban water systems is based on the past experience without considering the impact of climate change. The high temperature events in the recent summers in many cities of China have led to a series of high and record-breaking water demands, which were close to the limits of their water supply capacities. These events have revealed the vulnerability of urban water supply systems to the impcat of climate change. Selecting Beijing as the case study city, the project will apply a "climate analogy" method to investigate the impact of climate change on residential water use behaviours based on surveys in both the case study city and its "climate analogue". A water end-use model and a water distribution system model will be developed to simulate the impact of climate change on urban water demand and the distribution system and evaluate the vulnerability and thresholds of the water distribution system to climate change. And finally, adaptation strategies for the water distribution system will be proposed and their adaptive potentials be evaluated.

气候变化和快速城市化将会对城市区域脆弱的水资源系统产生强烈的影响。城市供水管网系统的使用寿命长达几十年至上百年，与气候变化效应的时间尺度相当，但传统的规划和设计都是基于历史经验的，而没有考虑气候变化因素。近几年，我国夏季高温天气导致很多城市供水量接连刷新历史记录，逼近供水能力极限，这些事件已经暴露出我国城市供水系统应对气候变化的脆弱性。本项目选择北京市作为案例城市，采用"气候相似性"研究方法，通过案例城市和气候相似城市的居民终端用水行为调查，识别气候变化对居民用水行为的影响。在此基础上，构建城市用水终端分析模型和供水管网系统模型，模拟气候变化对城市用水需求和城市供水管网系统的影响，评价城市供水管网系统应对气候变化的脆弱性及阈值，提出并评估应对策略的适应潜力。

气候变化和快速城市化将会对城市区域脆弱的水资源系统产生强烈的影响。城市供水管网系统的使用寿命长达几十年至上百年，与气候变化效应的时间尺度相当，但传统的规划和设计都是基于历史经验的，而没有考虑气候变化因素。为了研究气候变化对城市供水管网系统脆弱性的影响，本项目以北京市某区域的城市供水管网系统为研究对象，利用气候相似性分析方法识别出北京市未来、20世纪50年代以及极端高温气候特征的相似城市分别为现状的北京市、秦皇岛市以及衡阳市和深圳市。通过在北京市和气候相似城市开展居民用水行为调查，识别出淋浴和洗衣两种用水行为对平均气温的变化较为灵敏。利用本项目开发的基于居民终端用水和时间利用的城市用水量预测模型，模拟不同气候情景下案例区域供水管网系统的性能，结果表明按传统方法规划和设计的城市供水管网系统总体上可以应对平均气温升高2℃的气候条件，但不能应对升温3.5℃的气候条件。在城市供水管网系统中考虑气候变化因素、推广节水器具以及利用非传统水源可以有效减少案例区域供水管网系统中水头不足节点的数量，但会延长管网的水力停留时间。